Faculty Profiles - ITOH Takashi

Papers - ITOH Takashi

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Fabrication of Tilted Mg₂Si/Ni Multilayer Composite Modules Utilizing Polylactic Acid Resin Molds and Evaluation of The Thermoelectric Power Generation Performance Reviewed

Tomohiro KUSUMOTO, Yasuyoshi KUROKAWA, Noritaka USAMI, Takashi ITOH

J. Jpn. Soc. Powder Powder Metallurgy Vol. 72 ( Supplement ) page： S1269 - S1273 2025.3

Thermoelectric properties of Mg₂Si thin films prepared by thermal evaporation of Mg and face-to-face annealing Reviewed

Kurokawa, Y; Sato, K; Shibata, K; Kato, S; Miyamoto, S; Gotoh, K; Itoh, T; Usami, N

MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING Vol. 163 page： 107552 2023.8

Performance enhancement of droplet-based electricity generator using a CYTOP intermediate layer Reviewed

Wang Haitao, Kurokawa Yasuyoshi, Gotoh Kazuhiro, Kato Shinya, Yamada Shigeru, Itoh Takashi, Usami Noritaka

JAPANESE JOURNAL OF APPLIED PHYSICS Vol. 62 ( SC ) page： 1 - 6 2023.4

Morphology and Thermoelectric Properties of Mg_3+δSb₂ Foams Manufactured Using Combustion Synthesis Reviewed

Koga Takashi, Itoh Takashi

MATERIALS TRANSACTIONS Vol. 64 ( 4 ) page： 835 - 840 2023.4

Improved conversion efficiency of p-type BaSi₂/n-type crystalline Si heterojunction solar cells by a low growth rate deposition of BaSi₂ Reviewed

Michinobu Fujiwara, Kazuma Takahashi, Yoshihiko Nakagawa, Kazuhiro Gotoh, Takashi Itoh, Yasuyoshi Kurokawa, Noritaka Usami

AIP Advances Vol. 12 ( 4 ) page： 045115 2022.4

Fabrication of heterojunction crystalline Si solar cells with BaSi₂ thin films prepared by a two-step evaporation method Reviewed

Yoshihiko Nakagawa, Kazuma Takahashi, Michinobu Fujiwara, Kosuke O. Hara, Kazuhiro Gotoh, Yasuyoshi Kurokawa, Takashi Itoh, Takashi Suemasu, Noritaka Usami

JAPANESE JOURNAL OF APPLIED PHYSICS Vol. 60 ( 10 ) page： 105503-1 - 105503-6 2021.10

燃焼合成を利用して作製したMg_3+δSb₂発泡体の形態と熱電特性 Reviewed

古賀誉史, 伊藤孝至

粉体および粉末冶金 Vol. 68 ( 9 ) page： 399 - 404 2021.9

Trends in Development of Thermoelectric Power Generation Materials for Vehicle Invited Reviewed

Systems, Control and Information Vol. 65 ( 6 ) page： 201 - 206 2021.6

Quantitative Analysis on Influence of Structural Conditions on Thermoelectric Properties of Tilted Rod-Ni/Mg2Si Composites Based on Finite Element Simulation Reviewed

Itoh Takashi

MATERIALS TRANSACTIONS Vol. 62 ( 2 ) page： 246 - 251 2021

Synthesis of Mg₂Si thin film by thermal treatment under inert gas atmosphere and evaluation of film quality Reviewed

Issei Horiba, Michinobu Fujiwara, Yoshihiko Nakagawa, Kazuhiro Gotoh, Yasuyoshi Kurokawa, Takashi Itoh and Noritaka Usami

JAPANESE JOURNAL OF APPLIED PHYSICS Vol. 59 page： SFFB03-1 - SFFB03-5 2020.4

Language：Japanese Publishing type：Research paper (scientific journal)

We report on the synthesis of Mg₂Si thin films from a Mg-Si solution by thermal treatment of Mg on a Si substrate under an Ar gas atmosphere. The Mg was prepared by two methods. One is to deposit Mg films by thermal evaporation, and another is to simply place Mg ribbons on Si. After thermal treatment, a two-layer structure consisting of oxide and ~1 μm-thick Mg₂Si films with {100} preferential orientation was observed for the sample prepared by thermal evaporation. On the other hand, ~10 μm-thick single layer Mg₂Si with more random orientations and cracks was formed for the Mg ribbon contact samples. Possible mechanisms for different structures, crystal orientations, and crack formation are discussed.

DOI： 10.35848/1347-4065/ab6b79

Web of Science

Other Link： https://iopscience.iop.org/article/10.35848/1347-4065/ab6b79/meta

Optimization of Degreasing-Sintering Process for Mg₂Si/PLA Mixture and Influences of Additive Amount of Al on Sintered Density and Thermoelectric Performance of Mg₂Si Fabricated by the Optimized Process Reviewed

Takashi Itoh, Takumi Nakano

MRS Advances Vol. 5 ( 10 ) page： 459 - 467 2020

Language：English Publishing type：Research paper (scientific journal)

Fused deposition modelling (FDM) type of 3D printing is widely used for manufacturing complex shaped polymer products. Recently, the metal/polymer composite products can be made by 3D printer using metal/polymer composite filament. Now, we are planning to develop a new manufacturing process of the thermoelectric (TE) elements or modules by combining the FDM-type 3D printing and the degreasing-sintering process. In this work, we focused on the degreasing-sintering process of the mixture of Mg₂Si and polylactic acid (PLA) powders. Mg₂Si compound powder was synthesized by a liquid-solid phase reaction (LSPR) method. The powder mixtures of Mg₂Si, Al and PLA were pressed and heated in a pulse discharge sintering (PDS) chamber under a vacuum in various degreasing conditions. Following the degreasing, the sintering of Mg₂Si was carried out in the same PDS chamber at various starting sintering temperatures. Sintered density, Seebeck coefficient and electrical resistivity of the consolidated Mg₂Si were measured and the power factor as a TE performance was estimated from the TE properties. The optimum conditions of degreasing-sintering process maximizing the sintered density and the TE performance of Al-doped Mg₂Si were investigated. Furthermore, the influences of the additive amount of Al on the sintered density and the TE performance of Mg₂Si fabricated via the optimized degreasing-sintering process were investigated.

DOI： 10.1557/adv.2020.87

Web of Science

横方向熱電効果を有する Ni/Mg₂Si複合材料の熱電特性に関する有限要素シミュレーション解析 Reviewed

伊藤孝至

粉体および粉末冶金 Vol. 66 ( 2 ) page： 80-88 2019.2

有限要素シミュレーションに基づく傾斜棒状Ni/Mg₂Si複合材料の熱電特性に及ぼす構造条件の影響に関する定量解析 Reviewed

伊藤孝至

粉体および粉末冶金 Vol. 65 ( 11 ) page： 713-718 2018.11

Finite Element Simulation on Thermoelectric Performance of Tilted Mg₂Si/Ni Multilayer Composites Reviewed

Takashi Itoh

J. Jpn Soc. Powder and Powder Metallurgy Vol. 65 ( 3 ) page： 154-157 2018.3

Authorship：Lead author Language：English Publishing type：Research paper (scientific journal)

Mg₂Si is a promising n-type thermoelectric (TE) material for TE power generation using waste heat with temperature range of 300 to 600^oC. Construction of multilayer composites with Mg₂Si and metallic material brings anisotropy in TE properties and enhancement in mechanical properties. The transverse TE force is created by giving vertical temperature difference in the tilted anisotropic TE material (transverse TE effect). In this study, the tilted Mg₂Si/Ni multilayer composites were focused on, and the influences of the structural conditions on the TE performance were investigated using a finite element simulation (FES). The simulations were carried out using two types of element models of the multilayer composites with different thickness ratio and tilt angle of Mg₂Si layer under the same temperature conditions of 500^oC (hot side) and 100^oC (cold side). The output power of the multilayer composites as a TE performance was calculated from the open-circuit voltage and the internal resistance estimated using FES. The values changed with the thickness ratio and the tilt angle. The optimum structural conditions of thickness ratio and the tilt angle which maximized the output power of the tilted multilayer composites were found out.

DOI： 10.2497/jjspm.65.154

有限要素シミュレーションを用いたMg₂Si/Ni傾斜積層複合材料の熱電特性および性能の解析 Reviewed

伊藤孝至

粉体および粉末冶金 Vol. 64 ( 9 ) page： 501-509 2017.9

Cobalt and Iron Doping Effects on Thermoelectric Properties of Higher Manganese Silicides Prepared by Mechanical Milling and Pulse Discharge Sintering Reviewed

Takashi Itoh, Shinya Uebayashi

J. Jpn Soc. Powder and Powder Metallurgy Vol. 63 ( 7 ) page： 491-496 2016.7

Influence of Pulverization and CaO Nanoparticles Addition on Thermoelectric Properties and Grain Growth of Mg₂Si Based Compound Reviewed

Takashi Itoh, Akira Tominaga

Materials Transactions Vol. 57 ( 7 ) page： 1088-1093 2016.7

Thermoelectric Properties of Al-doped Mg₂Si Compounds Prepared via Three Kinds of Process for Grain Refinement Reviewed

Takashi Itoh, Akira Tominaga

MRS Advances Vol. 1 ( Issue 60 ) page： 3989 - 3995 2016.5

Thermoelectric Properties of Crystal Aligned Higher Manganese Silicide Fabricated by Solidification under Magnetic Field Reviewed

Kazushige Yamauchi, Takeshi Hagio, Tomoya Mitsuo, Kazuhiko Iwai, Takashi Itoh

Japanese Journal of Applied Physics Vol. 54 ( 11 ) page： 117102-1-6 2015.10

Language：English Publishing type：Research paper (scientific journal)

MnSi_1.73 is a promising p-type thermoelectric material for use in the intermediate-temperature region owing to its high oxidation resistance. Its thermoelectric properties are highly dependent on crystallographic direction and control of crystal alignment is thus important for polycrystalline MnSi_1.73. On the other hand, solidification under magnetic fields has been reported to directly yield crystal aligned structures in various alloys. Here, a 3T magnetic field was imposed during solidification of MnSi_1.73 for the first time. X-ray diffraction analysis indicated that polycrystalline MnSi_1.73 with c-axes aligned perpendicularly to the magnetic field was successfully obtained. The Seebeck coefficient slightly decreased while the electrical conductivity increased more than twofold along the magnetic field direction compared with those of the sample solidified without the magnetic field, which reflected the trend of a single crystal. The power factor reached a maximum of 2.09×10^-4 W m^-1K^-2 at 771 K; however, this was about one-fifth of that of a single crystal. Improvement in electrical conductivity by prevention of crack formation shall realize high performance expected from the crystal aligned structure.

DOI： 10.7567/JJAP.54.117102

Mg₂Si系化合物の熱電特性と粒成長に及ぼす粉砕とCaOナノ粒子添加の影響 Reviewed

伊藤孝至, 富永　彰

粉体および粉末冶金 Vol. 62 ( 3 ) page： 114-119 2015.3

粉末冶金プロセスを用いた環境調和型シリサイド系熱電変換材料の開発 Invited Reviewed

伊藤孝至

粉体および粉末冶金 Vol. 61 ( 11 ) page： 514-520 2014.11

Design of Segmented Thermoelectric Generator Based on Cost-effective and Light-weight Thermoelectric Alloys Reviewed

Hee Seok Kim, Keiko Kikuchi, Takashi Itoh, Tsutomu Iida, Minoru Taya

Materials Science and Engineering B Vol. 185 page： 45-52 2014.7

Language：English Publishing type：Research paper (scientific journal)

A segmented thermoelectric (TE) generator was designed with higher temperature segments composed of n-type Mg₂Si and p-type higher manganese silicide (HMS) and lower temperature segments composed of n- and p-type Bi-Te based compounds. Since magnesium and silicon based TE alloys have low densities, they produce a TE module with a high specific power density that is suitable for airborne applications. A two-pair segmented π-shaped TE generator was assembled with low contact resistance materials across bonding interfaces. The peak specific power density of this generator was measured at 42.9 W/kg under a 498 ^oC temperature difference, which has a good agreement with analytical predictions.

DOI： 10.1016/j.mseb.2014.02.005

液相‐固相反応法とパルス放電焼結法を用いて作製したMg₂Siの焼結性と熱電特性に及ぼすAl添加の影響 Reviewed

伊藤孝至, 富永　彰

粉体および粉末冶金 Vol. 61 ( 6 ) page： 324-328 2014.6

Influence of Aluminum Addition on Thermoelectric Performance of Mg₂Si Compound under Air Exposure with Temperature Difference Reviewed

T. Itoh, A. Tominaga

Mater. Res. Soc. Symp. Proc. Vol. 1642 page： Online mrsf13-1642-bb03-11 2014.5

Design of Linear Shaped Thermoelectric Generator and Self-integration Using Shape Memory Alloy Reviewed

Hee Seok Kim, Takashi Itoh, Tsutomu Iida, Minoru Taya, Keiko Kikuchi

Materials Science and Engineering B Vol. 183 page： 61-68 2014.4

液相－固相反応法で合成したMg₂Si系化合物の焼結性と熱電特性に及ぼすMg仕込量とB添加量の影響 Reviewed

富永　彰,　伊藤孝至

粉体および粉末冶金 Vol. 60 ( 8 ) page： 354-359 2013.8

半導体機器用Cr-Cu材ヒートシンクの焼結条件と溶浸性の関係 Reviewed

寺尾星明, 小日置英明, 太田裕樹, 伊藤孝至, 金武直幸

粉体および粉末冶金 Vol. 60 ( 8 ) page： 367-372 2013.8

Influence of Addition of Alumina Nanoparticles on Thermoelectric Properties of Higher Manganese Silicide Reviewed

T. Itoh, N. Ono

Mater. Res. Soc. Symp. Proc. Vol. 1490 page： Online mrsf12-1490-b09-31 2013.1

Influence of Addition of Alumina Nanoparticles on Thermoelectric Properties of La-filled Skutterudite CoSb₃ Compounds Reviewed

T. Itoh, M. Matsuhara

Materials Transactions Vol. 53 ( 10 ) page： 1801-1805 2012.10

Development of Cr-Cu Heat-sink(J-C'CREP®) for Semiconductor Device Reviewed

H. Terao, H. Kobiki, H. Ota, K. Tanabe, T. Itoh, N. Kanetake

Proc. 2012 Powder Metallurgy World Congress & Exhibition (PM2012) page： CD-ROM 16F-T14-13 2012.10

Development of Eco-Friendly Thermoelectric Silicide Compounds and Modules for Energy Harvesting Reviewed

T. Itoh, K. Nishigata

Proc. 2012 Powder Metallurgy World Congress & Exhibition (PM2012) page： CD-ROM 16E-S1-15 2012.10

Effects of Heavy Element Substitution on Electric Structure and Lattice Thermal Conductivity of Fe₂VAl Thermoelectric Material Reviewed

Y. Terazawa, M. Mikami, T. Itoh, T. Takeuchi

J. Electronic Materials Vol. 41 ( 6 ) page： 1348-1353 2012.6

Thermoelectric Properties of Mg₂Si-Based Compounds Synthesized Partially Using Magnesium Alloy Reviewed

T. Itoh, K. Hagio

AIP Conf. Proc. Vol. 1449 page： 207-210 2012.6

Language：English Publishing type：Research paper (scientific journal)

Mg₂Si compounds are promising eco-friendly thermoelectric materials because both constituent elements of Mg and Si have no toxicity and exist richly in earth crust. We have a plan to use the compounds in the applications that convert waste heat in the temperature range (600-900 K) into electric power. However, the thermoelectric performance of the compounds has not yet reached to the practical use level. In addition, the compounds don't have durability in the thermoelectric performance under atmospheric circumstances in the temperature range of 750-900 K. These issues have to be solved for the practical use. In our previous work, we obtained knowledge that Al doping in Mg₂Si lower the electrical resistivity and improved the thermoelectric performance. We newly attempted to use a magnesium alloy (AZ61) that includes the main three elements of aluminum (5.8-7.2 wt%), zinc (0.4-1.5 wt%) and manganese (0.15-0.35 wt%) in order to synthesize the Mg₂Si-based compounds. The Mg₂Si-based compound powders were synthesized from the mixture of silicon powder, AZ61 chips and Mg powder by the liquid-solid phase reaction method. The compound powders were sintered by the pulse discharge sintering method. The influence of mixing ratio of two metals of AZ61 and pure Mg on the thermoelectric properties was investigated. Addition of AZ61 greatly decreased the electrical resistivity as well as Al-doped Mg₂Si and the thermoelectric performance had improved most in the 50wt%AZ61 sample.

DOI： 10.1063/1.4731533

粉砕とパルス放電焼結を組合わせた方法による高マンガンシリサイドの合成とその熱電特性

伊藤孝至

日本熱電会誌 Vol. 8 ( 3 ) page： 18-21 2012.3

Fe₂VAlの電子構造と熱電物性における重元素部分置換効果 Reviewed

寺澤祐一，三上祐史，伊藤孝至，竹内恒博

日本金属学会誌 Vol. 76 ( 3 ) page： 216-221 2012.3

Synthesis of β-Zn₄Sb₃ Thermoelectric Nanoparticles by Reaction of Synthesized Sb Nanoparticles and Molten Zn Reviewed

T. Maruyama, T. Itoh

Proc. International Symposium on EcoTopia Science 2011 page： 234 2011.12

Solidification of MnSi_1.73 in A Magnetic Field Reviewed

T. Mitsuo, K. Iwai, T. Itoh

Proc. International Symposium on EcoTopia Science 2011 page： 43 2011.12

Development of Thermal Rectifier Using Unusual Electron Thermal Conductivity Reviewed

R. Nakayama, T. Itoh, T. Takeuchi

Proc. International Symposium on EcoTopia Science 2011 page： 173 2011.12

Synthesis of Ti-doped Higher Manganese Silicide by Pulse Discharge Sintering Reviewed

N. Ono, T. Itoh

Proc. International Symposium on EcoTopia Science 2011 page： 236 2011.12

Thermoelectric Properties of Mg₂Si-Based Compounds Synthesized Using Three Kinds of Magnesium Alloy Reviewed

K. Hagio, T. Itoh

Proc. International Symposium on EcoTopia Science 2011 page： 235 2011.12

Effect of Filling of Mg and Addition of Alumina Nanoparticles on Thermoelectric Properties of N-type La Filled CoSb₃ Compounds Reviewed

M. Matsuhara, T. Itoh

Proc. International Symposium on EcoTopia Science 2011 page： 237 2011.12

Thermoelectric Properties of n-type La-Mg Double Filled CoSb₃ Compounds Synthesized by MA-PDS Reviewed

T. Maruyama, T. Itoh

Proc. International Symposium on Materials Science and Innovation for Sustainable Society Vol. 2 page： 15-16 2011.11

Synthesis of Higher Manganese Silicide and It's Thermoelectric Property Reviewed

N. Ono, T. Itoh

Proc. International Symposium on Materials Science and Innovation for Sustainable Society Vol. 2 page： 11-12 2011.11

Thermoelectric Properties and Durability of Mg₂Si-Based Compounds Synthesized Using Magnesium Alloy Reviewed

K. Hagio, T. Itoh

Proc. International Symposium on Materials Science and Innovation for Sustainable Society Vol. 2 page： 13-14 2011.11

Thermoelectric Properties of Mg₂Si-based Compounds Synthesized Partially Using Magnesium Alloy Reviewed

T. Itoh, K. Hagio

Proc. 9th European Conference on Thermoelectrics page： CD-ROM B_39_P 2011.9

Development of Thermal Rectifier Usable at High Temperature Reviewed

T. Takeuchi, H. Goto, Y. Toyama, T. Itoh, M. Mikami

J. Electronic Materials Vol. 40 ( 5 ) page： 1129-1135 2011.5

Thermoelectric Properties of Carbon Nanotubes Added n-type CoSb₃ Compound Reviewed

T. Itoh, M. Tachikawa

Mater. Res. Soc. Symp. Proc. Vol. 1314 2011.5

Synthesis of Bi₂Te₃ Nanosheets using Polyol Process Reviewed

S. Nishiwaki, T. Itoh

IOP Conference Series: Materials Science and Engineering Vol. 18 2011.1

Thermoelectric Properties of Carbon Nanotubes Added n-type CoSb₃ Compound

T. Itoh and M. Tachikawa

2010 MRS Fall Meeting Abstracts page： CD-ROM ID:911936 2010.12

Fabrication and Thermoelectric Properties of Eco-Friendly Silicides for Thermoelectric Power Generation Using Waste Heat Reviewed

T. Itoh

Transactions of JWRI Vol. 39 ( 2 ) page： 276-278 2010.12

Synthesis of Bi₂Te₃ Nanosheets Using Polyol Process Reviewed

S. Nishiwaki and T. Itoh

3rd International Congress on Ceramics Abstracts page： CD-ROM, S9C-P019 2010.11

Fabrication and Thermoelectric Properties of Eco-Friendly Silicides for Thermoelectric Power Generation Using Waste Heat Reviewed

T. Itoh

The International Symposium on Advanced Materials Development and Integration of Novel Structured Metallic and Inorganic Materials Proc. page： 283-284 2010.11

Synthesis of Thermoelectric Bi-Sb Alloy by Liquid-Solid Phase Reaction Method Reviewed

S. Nishiwaki and T. Itoh

29th International Conference on Thermoelectric Abstracts page： 191 2010.6

Effect of Silicon Content on Thermoelectric Properties of Higher Manganese Silicide Compounds Prepared by Mechanical Grinding and Pulse Discharge Sintering

T. Itoh and M. Yoshikura

29th International Conference on Thermoelectric Abstracts page： 165 2010.6

ＭＧ－ＰＤＳ法で合成した高マンガンシリサイド化合物の熱電特性 Reviewed

吉倉雅晶，伊藤孝至

粉体および粉末冶金 Vol. 57 ( 4 ) page： 242-246 2010.4

修正ポリオールプロセスによる熱電Bi-Sb合金のナノ粒子合成 Reviewed

田中裕介,　伊藤孝至

粉体および粉末冶金 Vol. 57 ( 4 ) page： 252-256 2010.4

Effect of Alumina Nanoparticles Additions on Thermoelectric Properties of n-type CoSb₃ Compound Fabricated by Pulse Discharge Sintering Method Reviewed

Vol. 36 ( 2 ) page： 85-89 2010.3

Language：Japanese Publishing type：Research paper (scientific journal)

Thermoelectric power generation is a promising green energy system recovering waste heat. CoSb₃ skutterudite compound is a candidate material for thermoelectric power generation. For improving thermoelectric performance of the material, it is necessary to lower the thermal conductivity. In this work, Al₂O₃ nanoparticles were added and dispersed by mechanical grinding (MG) into n-type CoSb₃ compound prepared by pulse discharge sintering (PDS) method. Over long MG treatment brought high electrical resistivity, lowering thermoelectric performance of the Al₂O₃ nanoparticles added CoSb₃ compound. Seebeck coefficient almost did not change regardless of additional amount of Al₂O₃ nanoparticles. Increasing additional amount of Al₂O₃ nanoparticles brought increasing electrical resistivity and decreasing thermal conductivity. It is found that there is an optimal additional amount of Al₂O₃ nanoparticles that leads to improvement of thermoelectric performance of the CoSb₃ compound. The maximum thermoelectric performance (ZT=0.58) was achieved at 684K in the CoSb₃ compound including Al₂O₃ nanoparticles of 0.1mass%.

Development of Materials and Modules for Thermoelectric Power Generation Recovering Waste Heat Invited

T. Itoh

Abstracts of The 15th ATA Symposium (International Green Energy Conference) page： L-06 2009.11

Authorship：Lead author Language：English

The waste heat with intermediate temperature (300-600 oC) is discharged from many kinds of combustion systems, and the thermoelectric power generation is the most effective means for its recovery. Thus, the developments of the thermoelectric materials and modules working effectively in this temperature range are required. We developed the thermoelectric materials and modules for the thermoelectric power generation recovering the waste heat

Syntheses of Ni-doped and Fe-doped CoSb₃ Thermoelectric Nanoparticles through Modified Polyol Process Reviewed

T. Itoh and K. Isogai

Mater. Res. Soc. Symp. Proc. Vol. 1166 page： 135-140 2009.11

Authorship：Lead author Language：English Publishing type：Research paper (scientific journal)

Skutterudite CoSb₃ compounds are of increasing interest as materials with good thermoelectric performance over the temperature range of 600 to 800 K, but the thermal conductivity of the materials is relatively high. Nanostructured materials have been shown to enhance phonon scattering and lower the thermal conductivity of the thermoelectric materials. Partial substitution of Ni or Fe on the Co site of CoSb₃ is a hopeful route for improving thermoelectric performance of the CoSb₃ compounds. In the present work, synthesis of Ni-doped and Fe-doped CoSb₃ nanoparticles through the modified polyol process was attempted and the optimum synthesizing condition was investigated. Co(OOCH₃)₂·4H₂O, Ni(OOCH₃)₂·4H₂O, FeCl₃·6H₂O and SbCl₃, were prepared as precursors. The precursors were reduced by NaBH₄ in tetraethyleneglycol at 513 K in an argon atmosphere, for different reaction times (holding times). The reaction products were characterized by the X-ray diffraction, the energy dispersive X-ray spectroscopy, and transmission electron microscopy. The nanoparticles with about 20 to 30 nm in size mainly existed in the reaction products regardless of the chemical composition and the reaction time. The skutterudite phase was identified as a main phase in the sample synthesized for long reaction time, but the other phases of Sb and MSb₂ (M=Co, Ni, Fe) were also detected. The lattice parameter of the synthesized skutterudite phase linearly increased with increasing the doping agent concentration, following Vegard's law.

Synthesis of thermoelectric Bi-Sb alloy nanoparticles Reviewed

Y. Tanaka, T. Itoh

Abstracts of R'09 Twin World Congress page： 78 2009.10

Language：English

Binary Bi-Sb alloy is a material with an excellent thermoelectric performance in the low temperature region below 0 oC. It is a hopeful candidate material for thermoelectric power conversion using cold heat resource. Bi-Sb alloy is a complete solid solution. However, its synthesis is difficult in the fusion method due to gravity segregation, and its single crystal is very brittle. No segregation, high mechanical strength and low thermal conductivity are required for the thermoelectric Bi-Sb alloy. These properties can be achieved by making up a polycrystalline body from nanosized Bi-Sb alloy particles. In this study, we attempted to synthesize the nanoparticles of thermoelectric Bi-Sb alloy through a modified polyol process. Two kinds of materials, Bi( NO3)3.5H2O (1mmol) and SbCl3 (1mmol) were dissolved in tetraethyleneglycole (TEG, 20ml) as a solvent by sonicating. After the solution was bubbled with Ar gas and strongly agitated at room temperature, a reducing agent NaBH4 (320 mg) dissolved in TEG (10 ml) was added slowly, and the Bi-Sb alloy was synthesized by heating to 180 oC in Ar gas. The synthesized particles in the solution were settled by centrifugation, washed with ethanol and TEG, and dried under a vacuum. The syntheses of Bi-Sb alloy nanoparticles were also attempted in various experimental conditions. The reaction products were characterized by X-ray diffraction (XRD), and transmission electron microscopy (TEM). A single phase of Bi-rich Bi-Sb alloy was identified by XRD analysis. Agglomerate of the Bi-Sb alloy particles with nano-order size were confirmed by TEM observation.

Synthesis of Higher Manganese Silicide by Pulse Discharge Sintering Method Reviewed

M. Yoshikura, T. Itoh

Abtsracts of R'09 Twin World Congress Nagoya Venue page： 98 2009.10

Language：English

Higher manganese silicide (HMS) is a promising thermoelectric material available to thermoelectric power generation using the disposed heat resources of 500 to 900K. Since both of Mn and Si as constituent elements in the manganese silicide are harmless and they exist in abundance as mineral resources, the manganese silicide can become a low-cost thermoelectric material with low-environmental load. Though combination of mechanical alloying (MA) and pulse discharge sintering (PDS), that is a conventional method, may be an effective method for synthesizing HMS compound, difference of loss ratios of Mn and Si during MA process causes problems of composition shifts and poor reproductivity. In this study, a new synthesizing method of HMS was attempted. Mn and Si powders (75μm, 99.9%) were individually ground by mechanical grinding (MG) with a planetary ball milling equipment at 400 rpm for 1h. The ground powders with particle size of 44μm or less were collected by sieving. The collected Mn and Si powders were mixed at the molar ratio of 1:1.73 (a composition ratio of HMS) with a rotary blender at 75 rpm for 1h. HMS compound was synthesized from the mixed powder and simultaneously sintered by PDS at 1173K for 15 min under 60 MPa. From XRD analysis of the material consolidated by the new method, HMS phase was detected as a main phase, but MnSi phase was also detected as well as the material obtained by the conventional method. The synthesis was carried out under various experimental conditions, and thermoelectric properties were measured.

Influence of Carbon Nanotube Addition on Thermoelectric Properties of Skutterudite-type Cobalt Antimonide Compound Reviewed

M. Tachikawa, T. Itoh

Abstracts of R'09 Twin World Congress Nagoya Venue page： 98 2009.10

Language：English

Skutterudite-type cobalt antimonide compounds are well known as materials with good thermoelectric properties over temperature range of 300-600 oC. However, their thermal conductivity is relatively high, and lowering of the thermal conductivity is required for further improving thermoelectric performance. This study aims at lowering the lattice thermal conductivity by the phonon scattering induced from dispersing uniformly carbon nanotubes (CNTs) into the cobalt tri-antimonide compound. Powders of Co, Ni, Sb and Te were blended with molar ratios of n-type Co0.92Ni0.08Sb2.96Te0.04 compound, and the compound was synthesized through a pulse discharge sintering (PDS) process. After coarsely grinding the synthesized compound, CNTs were added into the compound powder at different fraction, and then the mixture was mechanically ground with a planetary ball milling equipment. The composite powder obtained by the mechanical grinding (MG) was compacted and sintered by PDS. Dispersion condition of CNTs was observed by scanning electron microscopy (SEM). Thermoelectric properties (Seebeck coefficient, electrical resistivity and thermal conductivity) of the sintered samples were measured. It was confirmed by SEM observation that the fibriform CNTs existed uniformly in the Co0.92Ni0.08Sb2.96Te0.04 compound matrix. The addition and dispersion of CNTs into the compound decreased the thermal conductivity, but increased the electrical resistivity.

Synthesis of Thermoelectric Manganese Silicide by Mechanical Alloying and Pulse Discharge Sintering Reviewed

T. Itoh and M. Yamada

J. Electronic Materials Vol. 38 ( 7 ) page： 925-929 2009.7

Authorship：Lead author Language：English Publishing type：Research paper (scientific journal)

Manganese silicide is a candidate for low-cost thermoelectric materials with low-environmental load. In this research, MnSi1.73 compound was studied as a thermoelectric material available for the thermoelectric power generation using waste heat. Manganese and silicon powders were mechanically alloyed under three different conditions (at 200 rpm for 36 ks, at 400 rpm for 3.6 ks and at 400 rpm for 36 ks) with a planetary ball milling equipment. Then, the mechanical alloyed powder was consolidated by a pulse discharge sintering process. Phases of MnSi1.73 (primary phase) and MnSi were synthesized in mechanical alloying and pulse discharge sintering. Thermoelectric properties were dependent on the mechanical alloying condition. The sample mechanically alloyed at 400 rpm for 3.6 ks had the best thermoelectric performance. The maximum dimensionless figure of merit ZT of 0.47 was achieved at 873K.

Thermoelectric Properties of Al-doped Mg₂Si Compounds Prepared by Liquid-Solid Phase Reaction and Pulse Discharge Sintering Reviewed

T. Itoh, M. Matsuno

Abstracts of ICT2009 page： 187 2009.7

Authorship：Lead author Language：English

Dimagnesium silicide is a candidate for thermoelectric materials available for the thermoelectric power generation using waste heat. This material has advantages of the constituent elements in abundance in the earth's crust and of the nontoxicity of its processing by-products as an environmental symbiosis thermoelectric semiconductor. Mg2Si Compounds doped with Al from 0 to 0.2 mol% were synthesized from Al, Mg and Si powders by a liquid-solid phase reaction method. The compounds were sintered through a pulse discharge sintering process. Influence of Al content on thermoelectric properties of Mg2Si compounds was investigated. Although Al-doping decreased the absolute value of Seebeck coefficient and increased the thermal conductivity, it drastically decreased the electrical resistivity. The maximum dimensionless figure of merit of 0.47 at 509 oC was achieved in Mg2Si doped with 0.2 mol% Al.

Syntheses of Ni-doped and Fe-doped CoSb₃ Thermoelectric Nanoparticles through Modified Polyol Process Reviewed

T. Itoh, K. Isogai

Abstracts of 2009 MRS Spring Meeting Vol. CD-ROM page： N3.16 2009.4

Authorship：Lead author Language：English

Skutterudite CoSb3 compounds are of increasing interest as materials with good thermoelectric performance over the temperature range of 600 to 800 K, but the thermal conductivity of the materials is relatively high. Nanostructured materials have been shown to enhance phonon scattering and lower the thermal conductivity of the thermoelectric materials. We have investigated about the synthesis of binary CoSb3 nanoparticles through a modified polyol process. Partial substitution of Ni or Fe on the Co site of CoSb3 is a hopeful route for improving thermoelectric performance of the CoSb3 compounds. In the present work, synthesis of Ni-doped and Fe-doped CoSb3 nanoparticles through the modified polyol process was attempted and the optimum synthesizing condition was investigated. Co(OOCH3)2.4H2O, Ni(OOCH3)2.4H2O, FeCl3 and SbCl3, were prepared as precursors. The precursors were reduced by NaBH4 in tetraethyleneglycol at 513 K in argon gas, for different reaction time (holding time). The reaction products were characterized by the X-ray diffraction, the energy dispersive X-ray spectroscopy, and transmission electron microscopy. The nanoparticles with about 20 to 30 nm in size mainly existed in the reaction products regardless of the chemical composition and the reaction time. The skutterudite phase was identified as a main phase in the sample synthesized for long reaction time, but the other phases of Sb and MSb2 (M=Co, Ni, Fe) were also detected. The lattice parameter of the synthesized skutterudite phase linearly increased with increasing the doping agent concentration, following Vegard's law.

新たな手法による熱電発電用モジュールの作製とその特性評価 Reviewed

生田裕二，伊藤孝至

粉体および粉末冶金 Vol. 56 ( 1 ) page： 30-34 2009.1

圧縮ねじり成形法によるBi-Sb-Te系熱電材料の固化と組織制御 Reviewed

伊藤孝至, 門井　崇, 金武直幸

日本金属学会誌 Vol. 73 ( 1 ) page： 1-6 2009.1

液相－固相反応法によるマグネシウムシリサイド化合物の合成とその熱電特性 Reviewed

松野光晴, 伊藤孝至

粉体および粉末冶金 Vol. 56 ( 1 ) page： 26-29 2009.1

Thermoelectric Properties of Sintered Bodies Made of Synthesized CoSb3 Nanoparticles

K. Isogai and T. Itoh

Abstracts of The IUMRS International Coference in Asia 2008 page： CD-ROM UP-10 2008.12

Language：English

CoSb3 based skutterudite compounds are the promising thermoelectric materials that have relatively good thermoelectric properties with respect to the Seebeck
coefficient and the electrical resistivity over temperature range of 600-800 K. The high thermal conductivity of the materials, however, prevents from achieving high thermoelectric performance. Superfine
grain structure made by sintering superfine particles is expected to lower the thermal conductivity by phonon scattering. In our previous work, we have reported the CoSb3 nanoparticles synthesis via a modified polyol process. In the present work, we focused at investigating the thermoelectric properties of the sintered bodies made of the synthesized CoSb3 nanoparticles. The CoSb3 nanoparticles were synthesized via the modified polyol process. Two reactants Co(OOCH3)2·4H2O and SbCl3 were mixed
at a stoichiometric mole ratio of 1:3, and were reacted with a reducing agent NaBH4 in a solvent tetraethyleneglycol at 513 K. Then, the reaction products were sintered into bulk samples by a pulse discharge
sintering (PDS) under several operating conditions. The synthesized nanoparticles and the sintered samples were
characterized with respect to the synthesized phases, the particle size and the grain size. The Seebeck coefficient, the electrical resistivity and the thermal conductivity of the sintered samples were also measured. The nanoparticles with size about 20 to 30 nm mainly existed in the reaction products. The CoSb3 phase was identified, but the other phases of Sb and CoSb2 were also detected. It was found
that the synthesis of CoSb3 is promoted by PDS process. In the sample sintered at 853K for 15min under 60MPa, the grains with size about 200nm mainly existed together with several tens nanometer sized grains. The thermal conductivity of the fine grain sized sample was sufficiently reduced compared with that of the sample
synthesized and sintered by only PDS process.

The effect of the sintering conditions and addition of fullerene on thermoelectric properties of Mg₂Si

M. Matsuno and T. Itoh

Abstracts of The IUMRS International Coference in Asia 2008 page： CD-ROM UP-9 2008.12

Language：English

Magnesium silicide (Mg2Si) is a promising material for thermoelectric energy conversion at intermediate temperature range. This material has advantages of the abundance of its constituent elements in the earth's crust and of the nontoxicity of its processing by-products as an environmentally friendly thermoelectric semiconductor. However, there are few research reports about this material for improving thermoelectric performance because of difficulty of its synthesis. In this study, Mg2Si was synthesized from Mg and Si by a liquid-solid phase reaction (LSPR) method, which is effective in synthesizing a compound from the two elements having sufficiently different melting points. The powder synthesized by LSPR method was compacted and then sintered by a pulse discharge sintering (PDS) process. All sintered samples indicated the nature of n-type semi-conductor over a measuring temperature range. The power factor of the sintered sample was, however, strongly affected by the sintering temperature and/or the sample density. The sample sintered at 1003 K for 30 min under 60MPa had the maximum power factor of about 0.11×10-2 mWm-1K-2 at 464 K. Mg2Si powder was mixed with fullerene by a planetary ball milling method, and then sintered by PDS process. In the samples sintered under the same sintering condition, the power factor decreased with fullerene addition, because the electrical resistivity considerably increased and/or the sample density decreased. It will be necessary to optimize the sintering conditions for attaining an effective result about the fullerene addition.

Fabrication of Thermoelectric Module by A New Manufacturing Process and Its Performance

Y. Ikuta and T. Itoh

Abstracts of The IUMRS International Coference in Asia 2008 page： CD-ROM UP-8 2008.12

Language：English

In the conventional production of the thermoelectric modules, process automation is difficult since the thermoelectric elements are produced by slicing only one at a time and the assembly of thermoelectric modules requires placement and attachment of the individual, and sometimes very small, thermoelectric elements. This leads to high production cost. Thus, new processing methods will be required for cost-effectively producing compact thermoelectric modules with a multitude of thermoelectric couples. In the present work, a new manufacturing process was attempted for producing the thermoelectric modules, and performances of the modules were evaluated. Powders of the p-type FeCo3Sb12 and the n-type Co0.92Ni0.08Sb2.96Te0.04 compounds were alternately filled into 4x4 square holes of an insulating mold. The powders in the holes were compacted and sintered simultaneously at 900 K in vacuum for 20 min under the isostatic pressure of 60 MPa. In sintering, a pseudo hot isostatic pressing (pseudo HIP) method, in which one-directional load is transmitted isostatically to the sample through the alumina powder filled around the sample, were used to prevent the mold from breaking. The sintered elements in the mold were electrically connected in series using silver paste. Then, a thermoelectric module was constructed by parallel sandwiching the mold with glass plates of 0.5mm in thickness. The hot side of the module was heated up to 796 K, and the cold side was
cooled by water. Under this condition, the thermoelectric performance was evaluated. The maximum open voltage was 561 mV at the maximum temperature difference of 356 K, and the internal resistance in the module was 1.74 Ω. In this case, the output power of 50.1 mW was obtained and the power density of 51.1 mW/cm2 was estimated. The value of output power was less than that of the theoretical calculation. This can be attributed to the high internal resistance due to the low sintering density of each thermoelectric element.

Thermoelectric Properties of Sintered Bodies Made of Synthesized CoSb₃ Nanoparticles

K. Isogai and T. Itoh

Abstracts of The IUMRS International Coference in Asia 2008 page： CD-ROM UP-10 2008.12

Language：English

CoSb3 based skutterudite compounds are the promising thermoelectric materials that have relatively good thermoelectric properties with respect to the Seebeck coefficient and the electrical resistivity over temperature range of 600-800 K. The high thermal conductivity of the materials, however, prevents from achieving high thermoelectric performance. Superfine grain structure made by sintering superfine particles is expected to lower the thermal conductivity by phonon scattering. In the present work, we focused at investigating the thermoelectric properties of the sintered bodies made of the synthesized CoSb3 nanoparticles. The CoSb3 nanoparticles were synthesized via the modified polyol process. Two reactants Co(OOCH3)2·4H2O and SbCl3 were mixed at a stoichiometric mole ratio of 1:3, and were reacted with a reducing agent NaBH4 in a solvent tetraethyleneglycol at 513 K. Then, the reaction products were sintered into bulk samples by a pulse discharge sintering (PDS) under several operating conditions. The nanoparticles with size about 20 to 30 nm mainly existed in the reaction products. The CoSb3 phase was identified, but the other phases of Sb and CoSb2 were also detected. It was found that the synthesis of CoSb3 is promoted by PDS process. In the sample sintered at 853K for 15min under 60MPa, the grains with size about 200nm mainly existed together with several tens nanometer sized grains. The thermal conductivity of the finegrain sized sample was sufficiently reduced compared with that of the sample synthesized and sintered by only PDS process.

Fabrication of Thermoelectric Module by A New Manufacturing Process and Its Performance

Y. Ikuta and T. Itoh

Abstracts of The IUMRS International Coference in Asia 2008 page： CD-ROM UP-8 2008.12

Language：English

In the conventional production of the thermoelectric modules, process automation is difficult since the thermoelectric elements are produced by slicing only one at a time and the assembly of thermoelectric modules requires placement and attachment of the individual, and sometimes very small, thermoelectric elements. This leads to high production cost. Thus, new processing methods will be required for cost-effectively producing compact thermoelectric modules with a multitude of thermoelectric couples. In the present work, a new manufacturing process was attempted for producing the thermoelectric modules, and performances of the modules were evaluated. Powders of the p-type FeCo3Sb12 and the n-type Co0.92Ni0.08Sb2.96Te0.04 compounds were alternately filled into 4x4 square holes of an insulating mold. The powders in the holes were compacted and sintered simultaneously at 900 K in vacuum for 20 min under the isostatic pressure of 60 MPa. In sintering, a pseudo hot isostatic pressing (pseudo HIP) method were used to prevent the mold from breaking. The sintered elements in the mold were electrically connected in series using silver paste. Then, a thermoelectric module was constructed by parallel sandwiching the mold with glass plates of 0.5mm in thickness. The hot side of the module was heated up to 796 K, and the cold side was cooled by water. The maximum temperature difference between the hot and cold sides was 356 K. The maximum open voltage was 561 mV at the maximum temperature difference of 356 K, and the internal resistance in the module was 1.74 . The output power of 50.1 mW was obtained and the power density of 51.1 mW/cm2 was estimated. The value of output power was less than that of the theoretical calculation. This can be attributed to the high internal resistance due to the low sintering density of each thermoelectric element.

The effect of the sintering conditions and addition of fullerene on thermoelectric properties of Mg2Si

M. Matsuno and T. Itoh

Abstracts of The IUMRS International Coference in Asia 2008 page： CD-ROM UP-9 2008.12

Language：English

Magnesium silicide (Mg2Si) is a promising material for thermoelectric energy conversion at intermediate temperature range. This material has advantages of the
abundance of its constituent elements in the earth's crust and of the nontoxicity of its processing by-products as an environmentally friendly thermoelectric semiconductor. However, there are few research reports about this material for improving thermoelectric performance because of difficulty of its synthesis. In this study, Mg2Si was synthesized from Mg and Si by a liquid-solid phase reaction (LSPR) method, which is effective in synthesizing a compound from the two elements having sufficiently different melting points. Firstly, the influence of sintering conditions on the thermoelectric properties of Mg2Si was investigated. The powder synthesized by LSPR method was compacted and then sintered by a pulse discharge sintering (PDS) process. Thermoelectric properties, that is, Seebeck coefficient, electrical resistivity and thermal conductivity of each sintered sample were measured at temperature of 300 to 900 K. All sintered samples indicated the nature of n-type semiconductor over a measuring temperature range. The power factor of the sintered sample was, however, strongly affected by the sintering temperature and/or the sample density. The sample sintered at 1003 K for 30 min under 60MPa had the maximum power factor of about 0.11×10-2 mWm-1K-2 at 464 K. This value is higher than the previous report. Secondly, we attempted to add and disperse the fullerene nanoparticles into Mg2Si compound for lowering the thermal conductivity according to the knowledge obtained in our previous work. Mg2Si powder was mixed with fullerene by a planetary ball milling method, and then sintered by PDS process. In the samples sintered under the
same sintering condition, the power factor decreased with fullerene addition, because the electrical resistivity considerably increased and/or the sample density decreased.

Synthesis of Co_1-xNi_xSb₃ Thermoelectric Nanoparticles

K. Isogai, T. Itoh and K. Kitagawa

Abstracts of The 14th International Symposium on Advanced Technology and Applications (ATA) page： 42 2008.11

Language：English

Cobalt-antimony skutterudite compounds have a relatively high power factor over a temperature range of 600 to 800 K, but its thermal conductivity is relatively high. Nanostructuring is expected to lower the lattice thermal conductivity by grain boundary phonon scattering, improving the thermoelectric performance of the materials. Partial substitution of Ni on the Co site of CoSb3 is a hopeful route for obtaining n-type CoSb3-based skutterudite. In the present work, synthesis of Co1-xNixSb3 thermoelectric nanoparticles by the modified polyol process was attempted and the optimum synthesizing condition was investigated. Co(OOCH3)2·4H2O, Ni(OOCH3)2·4H2O and SbCl3 were mixed at the desired composition of x<0.1, and they were reduced by NaBH4 in tetraethyleneglycol at 513 K in an atmosphere of argon gas, for different reaction time (holding time). The nanoparticles of sizes ranging from about 20 to 30 nm mainly existed in the reaction products regardless of the composition and the reaction time. The skutterdite phase is identified as the main phase in the sample synthesized for the longer reaction time, but the other phases of Sb and MSb2 (M=Co, Ni) are also detected. The lattice constant of the synthesized skutterudite phase was almost linearly increased with Ni content. This is in good agreement with the Vegard's law.

Synthesis of Co1-xNixSb3 Thermoelectric Nanoparticles Reviewed

K. Isogai, T. Itoh and K. Kitagawa

Abstracts of The 14th International Symposium on Advanced Technology and Applications (ATA) page： 42 2008.11

Language：English

Cobalt-antimony skutterudite compounds have a relatively high power factor over a temperature range of 600 to 800 K, but its thermal conductivity is relatively high. Nanostructuring is expected to lower the lattice thermal conductivity by grain boundary phonon scattering, improving the thermoelectric performance of the materials. In our previous work, we have reported about the synthesis of p-type CoSb3 nanoparticles via a modified polyol process. Partial substitution of Ni on the Co site of CoSb3 is a hopeful route for obtaining n-type CoSb3-based skutterudite. In the present work, synthesis of Co1-xNixSb3 thermoelectric nanoparticles by the modified polyol process was attempted and the optimum synthesizing condition was investigated. Co(OOCH3)2·4H2O, Ni(OOCH3)2·4H2O and SbCl3 were mixed at the desired composition of x<0.1, and they were reduced by NaBH4 in tetraethyleneglycol at 513 K in an atmosphere of argon gas, for different reaction time (holding time). The reaction products were characterized by the X-ray diffraction, the energy dispersive X-ray spectroscopy, and transmission electron microscopy.The nanoparticles of sizes ranging from about 20 to 30 nm mainly existed in the reaction products regardless of the composition and the reaction time. The skutterdite phase is identified as the main phase in the sample synthesized for the longer reaction time, but the other phases of Sb and MSb2 (M=Co, Ni) are also detected. The lattice constant of the synthesized skutterudite phase was almost linearly increased with Ni content. This is in good agreement with the Vegard's law.

Synthesis of Thermoelectric Manganese Silicide by Mechanical Alloying and Pulse Discharge Sintering

T. Itoh and M. Yamada

Abstracts of ICT2008 (27th International Conference on Thermoelectric) page： 53 2008.8

Authorship：Lead author Language：English

Global energy and environmental issues are problems to be urgently solved. Thermoelectric power generation is a hopeful method to decrease dependence of fossil fuels and to promote the environmental safeguards. In this research, manganese silicide MnSi1.73 was focused as one of the promising thermoelectric materials available to the thermoelectric power generation using the disposed heat resources of 500 to 900K. Since both of Mn and Si as constituent elements in the manganese silicide are harmless and they exist in abundance as mineral resources, the manganese silicide can become a low-cost thermoelectric material with low-environmental load. Raw powders of manganese and silicon were mechanically alloyed through a planetary ball milling under the different milling time and the different rotating speed. Then the mechanical alloyed powder was consolidated through a pulse discharge sintering process (at 1023 K for 20 min in vacuum under a pressure of 100 MPa). The manganese silicide phases of MnSi1.73 (primary phase) and MnSi were synthesized in mechanical alloying and pulse discharge sintering. The thermoelectric properties were dependent on an XRD intensity ratio of MnSi1.73 to MnSi. The maximum dimensionless figure of merit ZT of 0.47 was achieved at 873K.

Effect of Combined Addition of Silicon Carbide Whiskers and Fullerene Nanoparticles on Properties of Thermoelectric Zinc Antimonide Reviewed

T. Itoh, N. Asari, N. Kanetake, A. Okada

Mater. Res. Soc. Symp. Proc. Vol. 1044 page： 265-272 2008.4

Authorship：Lead author Language：English Publishing type：Research paper (scientific journal)

Thermoelectric power generation is a hopeful method harnessing waste thermal energy particularly covering a middle temperature range between 500 and 800 K. A Zn4Sb3 compound is a promising "phonon glass electron crystal" material applicable to thermoelectric power generation around 700 K. This material, however, has a problem of its brittleness. In this research, the silicon carbide whiskers were added into the Zn4Sb3 compound for overcoming the brittleness, and the fullerene nanoparticles were also added for improving the thermoelectric performance. The Zn4Sb3 compound was synthesized from mixture of pure zinc and antimony powders by a liquid-solid phase reactions method. Firstly, the synthesized compound powder was mixed with the fullerene nanoparticles. The planetary ball milling method was used in order to disentangle the fullerene agglomerate and to obtain a uniform mixture. Subsequently, the mixture was uniformly mixed with the SiC whiskers by the planetary ball milling. The final mixture was consolidated by the pulse discharge sintering. The synthesized phases were identified by XRD. The morphology of the whiskers after mixing was observed. The flexural strength and the thermoelectric properties of the sintered samples were measured. The length of SiC whiskers and the flexural strength were decreased with the mixing time. Though the addition of SiC whiskers lowered the thermoelectric performance, the combined addition of SiC whiskers and fullerene nanoparticles restored the performance especially through a decrease of the thermal conductivity owing to the phonon scattering.

Thermoelectric Properties of β-Zn4Sb3 Synthesized by Mechanical Alloying and Pulse Discharge Sintering Reviewed

T. Itoh, J. Shan and K. Kitagawa

J. Propulsion and Power Vol. 24 ( 2 ) page： 353-358 2008.3

Authorship：Lead author Language：English Publishing type：Research paper (scientific journal)

Thermoelectric power generation is a hopeful method for harnessing waste thermal energy, particularly covering a middle temperature range between 500 and 800 K. A β-Zn4Sb3 compound has become the focus of attention as a thermoelectric material applicable to thermoelectric power generation around 700 K. In this research, a method combining the mechanical allying with the pulse discharge sintering was adopted to obtain the sintered compact of β-Zn4Sb3. Pure zinc and antimony powders were used as the starting material for mechanical alloying. These powders were mixed in the stoichiometry ratio of 4 to 3, or more Zn-rich. The mechanical alloying was carried out by planetary ball milling under conditions of fixed revolution speed and variable milling time. The influence of the milling time on the synthesis of β-Zn4Sb3 was investigated. The sintering was executed at two sintering temperatures and under fixed conditions of sintering time, pressing pressure, and atmosphere. The influences of the sintering temperature of pulse discharge sintering on the polycrystalline grain size and the thermoelectric properties were also studied. The following results were clarified. The phases of ZnSb and Zn are easily obtained by mechanical alloying for 50 h or longer time. These phases change to a single phase of β-Zn4Sb3 through pulse discharge sintering under the optimum condition of Zn-rich mixing. The sintered compact of β-Zn4Sb3 with 1.17 of nondimensional figure of merit can be obtained at 673 K with the proposed mechanical alloying with pulse discharge sintering method.

Thermoelectric Properties of Iron-and Lanthanum-Doped CoSb3 Compounds by Pulse Discharge Sintering Reviewed

T. Itoh, E. Hattori and K. Kitagawa

J. Propulsion and Power Vol. 24 ( 2 ) page： 359-364 2008.3

Authorship：Lead author Language：English Publishing type：Research paper (scientific journal)

More than 60% of thermal energy generated through various combustion systems is discharged as waste heat into the atmosphere. Using the waste heat effectively is among the most important issues from a viewpoint of the depletion
of fossil fuels. In this regard, thermoelectric power generation that can directly convert the thermal energy to
electrical energy is one of the attractive methods. Skutterudite compounds of CoSb3 have been investigated as promising candidate materials for thermoelectric power generation. In this research, CoSb3 compounds were synthesized from raw metal powders by using a pulse discharge sintering process. To improve the thermoelectric properties, iron was doped as an element substituting for cobalt of the CoSb3 compound. The syntheses of FexCo1-xSb3 were confirmed by x-ray diffraction analysis. The Seebeck coefficient, electric resistivity, and thermal conductivity were measured as the thermoelectric properties. Optimum content of iron was decided from the maximum thermoelectric figure of merit. Furthermore, filling of lanthanum into Fe0.1Co0.9Sb3 was attempted to decrease the thermal conductivity. The lanthanum-filled Fe0.1Co0.9Sb3 compounds were synthesized from raw metal powders and LaSb powder by the pulse discharge sintering process. The optimum lanthanum content that leads to the maximum thermoelectric performance is discussed. The substitution of iron for cobalt improved the thermoelectric performance. The lanthanum-filling decreased the thermal conductivity at a low lanthanum content and led to higher thermoelectric performance in spite of low lanthanum content.

Effect of Acid Treatment on Removing Sodium Ions from Sodium Cobalt Oxide Thermoelectric Materials

R. Watanabe, T. Itoh, K. Kitagawa

Proc. of International Symposium on EcoTopia Science 2007 page： CD-ROM 23P01-13 (1100) 2007.11

Language：English

NaxCo2O4 with a laminar structure is a promising thermoelectric oxide having anisotropic thermoelectric property. An excellent thermoelectric performance equivalent to the single crystal is expected to be attainable in the polycrystalline body of this material by improvement of crystal orientation. It will be effective for controlling the crystal orientation to separate CoO2 nanosheets from the polycrystalline body and to pile them up for making highly orientated layers. This study aims at preparation of the CoO2 nanosheets. First, samples of NaxCo2O4 were synthesized. The interlayer Na+ ions were removed from the CoO2 layers of the synthesized powder by an acid treatment. The interlayer distance of the synthesized and the Na+ ion removed samples was measured by XRD analysis. The removal efficiency of Na+ ions was evaluated from ICP measurement. The morphology of the samples was observed by a SEM. We found that the condition of the acid treatment greatly influences the removal efficiency of Na+ ions in the synthesized NaxCo2O4.

Polyol Process Synthesis of CoSb3 Termoelectric Nanoparticles Reviewed

K. Isogai, T. Itoh

Proc. of International Symposium on EcoTopia Science 2007 page： CD-ROM 23P01-15 (1122) 2007.11

Language：English

The cobalt-antimony skutterdite compounds have relatively high power factor at around 380 oC, but they have relatively high thermal conductivity. Nanostructuring is expected to lower the lattice thermal conductivity by phonon scattering on the grain boundary, improving the thermoelectric performance of the materials. In this study, we aim at synthesizing CoSb3 thermoelectric nanoparticles by using polyol process for constructing the nanostructural body of the materials. The polyol process that synthesizes nanoparticles is one of liquid-phase process using polyol as a solvent. The CoSb3 nanoparticles were syn-thesized in mole ratio of Co(OOCH3)·4H2O to SbCl3 of 1:4.5 at reaction temperature of 240 oC in the sol-vent of tetra ethylene glycol. The reaction products were characterized by XRD, EDX, SEM, and TEM. Extremely small particles with about 10 nm in diameter mainly existed in the reaction products. The minimum particle size was 3-5 nm. The nanoparticles were identified as the CoSb3 compounds.

Influence of Fullerene Addition on Thermoelectric Properties of Non-filled/Filled Cobalt-Skutterudite Compounds Reviewed

K. Ishikawa, A. Okada, T. Itoh

Proc. of International Symposium on EcoTopia Science 2007 page： CD-ROM 23P01-14 (1101) 2007.11

Language：English

The cobalt-skutterudite compounds are promising thermoelectric materials having relatively good thermoelectric properties with respect to the Seebeck coefficient and the electrical resistivity over the temperature range between 500 and 800K. The high thermal conductivity of the materials, however, prevents from achieving high thermoelectric performance. In this study, we attempted to disperse the fullerene particles uniformly into the cobalt-skutterudite compounds for decreasing the lattice thermal conductivity by phonon scattering. The influence of the fullerene addition on the thermoelectric properties was investigated with respect to both of the n-type non-filled and filled cobalt-skutterudite compounds. The n-type lanthanum-filled cobalt-skutterudite compound was synthesized via the route of mechanical alloying-pulse discharge sintering process. In both of the non-filled and the filled skutterudite samples, the thermal conductivity was decreased with the addition of fullerene. For the non-filled skutterudite, though the electrical resistivity of the samples was increased with the addition of fullerene, the thermoe-lectric performance was improved.

Consolidation and Microstructure Control of Bismuth Telluride Thermoelectric Compounds by Compressive Torsion Forming Reviewed

T. Itoh, T. Kadoi and N. Kanetake

Materials Transactions Vol. 48 ( 8 ) page： 2056-2061 2007.8

Authorship：Lead author Language：English Publishing type：Research paper (scientific journal)

Bismuth antimony telluride has the best performance among the p-type thermoelectric materials used in the range of temperature between 300K and 500K. This material has a trigonal-hexagonal scalenohedral crystal structure and the cleavage parallel to the basal plane of the crystal can readily occur. Suppression of the electrical resistivity and the thermal conductivity will be effective for further
improvement of the performance of the thermoelectric elements made from this material. The compressive torsion forming is the severe plastic deformation technique, in which the loads of compression and distortion are simultaneously subjected to the materials without change in its shape. In this work, we applied this technique to the powder of bismuth antimony telluride for consolidation and improvement of the thermoelectric performance by refining the grain structure and by controlling the crystal orientation. The samples consolidated under various forming conditions were investigated with respect to density, microstructure, XRD, texture, and thermoelectric properties. It was found out that the compressive torsion forming is effective for the microstructure control, the grain structure less than
10μm can be obtained, and the thermoelectric performance is
obviously improved by the compressive torsion forming.

*Effect of Fullerene Addition on Thermoelectric Properties of n-type Skutterudite Compound Reviewed

T. Itoh, K. Ishikawa, and A. Okada

Journal of Materials Research Vol. 22 ( 1 ) page： 249-253 2007.1

Prediction of Packing Density of Milled Powder Based on Packing Simulation and Particle Shape Analysis Reviewed

Y. Amano, T. Itoh, H. Terao and N. Kanetake

Materials Science Forum Vol. 534-536 page： 1621-1624 2007.1

Fabrication of the Crystal-Oriented Thermoelectric Material Bi2Te3 by Slip Casting under a High Magnetic Field Reviewed

T. Kuribayashi, M. Sung, T. Itoh, K. Sassa, and S. Asai

Materials Transactions Vol. 47 ( 9 ) page： 2387-2392 2006.9

Prediction of Packing Density of Milled Powder Based on Packing Simulation and Particle Shape Analysis Reviewed

Y. Amano, T. Itoh, H. Terao, and N. Kanetake

Extended Abstracts 2006 World Congress on Powder Metallurgy & Particulate Materials, KPMI page： 1254-1255 2006.9

Performance of Segmented Thermoelectric Elements Fabricated by Simultaneous Sintering Method Reviewed

T. Itoh, T. Muto, and K. Kitagawa

Proceedings 25th International Conference on Thermoelectric, IEEE ( CD-ROM ) page： PB48 2006.8

アルミニウムの結晶粒微細化に及ぼす圧縮ねじり複合負荷の効果 Reviewed

金武直幸，青野圭太郎，伊藤孝至，久米裕二

軽金属 Vol. 56 ( 1 ) page： 34-38 2006.1

Fabrication of Segmented n-type CoSb3/Bi2Te3 Thermoelectric Module and Its Performance Reviewed

T. Muto, T. Itoh, N. Kanetake and K. Kitagawa

Extended Abstracts International Symposium on EcoTopia Science 2005 page： 587-588 2005.8

Syntheses of Fe and La Doped CoSb3 Thermoelectric Compounds by Pulse Discharge Sintering Reviewed

T. Itoh, E. Hattori and K. Kitagawa

Extended Abstracts International Symposium on EcoTopia Science 2005 page： 219-220 2005.8

Fabrication of Segmented p-type AgSbTe2/Sb2Te3/Bi0.4Sb1.6Te3 Thermoelectric Module and Its Performance Reviewed

T. Muto, K. Tokuda, T. Itoh and K. Kitagawa

Proceedings 24th International Conference on Thermoelectrics, IEEE page： 521-524 2005.6

Thermoelectric Properties of beta- Zn4Sb3 Synthesized by MA- SPS Method Reviewed

T. Itoh, J. Shan and K. Kitagawa

Proceedings The 2nd International Energy Conversion Engineering Conference (IECEC2004), AIAA page： AIAA-2004-5564 2004.8

Synthesis of CoSb3 compound and its thermoelectric properties Reviewed

Vol. 51 ( 6 ) page： 441-446 2004.6

米国粉末冶金界が求める技術情報の変遷と軟磁性に及ぼす焼結組織の影響 Reviewed

鰐部吉基,草加勝司,横山誠二,伊藤孝至

粉体および粉末冶金 Vol. 51 ( 6 ) page： 458-461 2004.6

Multi-layer coating of SiC, Al2O3 and glaze on C/C composites for oxidation resistance at high temperature Reviewed

Q. Shen, J. Shan, T. Itoh, K. Kitagawa

Journal of the Japan Society of Powder and Powder Metallurgy Vol. 51 ( 4 ) page： 237-241 2004.4

Fabrication of segmented p-type AgSbTe2 - (Bi,Sb)2Te3 thermoelectric module and its Performances Reviewed

Vol. 51 ( 1 ) page： 10-15 2004.1

Fabrication of Layered p-type AgSbTe2-(Bi,Sb)2Te3 thermoelectric module and its performance (jointly authored) Reviewed

M. Kobo, T. Itoh, K. Tokuda, J. Shan and K. Kitagawa

Proceedings of 2003 International Conference on Thermoelectrics, International Thermoelectric Society page： 429-432 2003.8

Formation of an Environmental Barrier Coating Using DC-RF Hybrid Plasma Reviewed

A. Otsuka, M. Yamamoto, T. Itoh, K. Kitagawa and S. Hirano

Journal of American Ceramic Society Vol. 86 ( 7 ) page： 1068-1075 2003.7

Microstructural Dependency of Soft Magnetism in a Sintered Stainless Fe-12%Cr Alloy Reviewed

Y.Wanibe,T. Itoh and K. Kusaka

Advances in Powder Metallurgy & Particulate Materials -2003, MPIF ( 7 ) page： 14-27 2003.6

Quantitative Assesment of Pores Reviewed

J. Jpn Soc. Powder and Powder Metallurgy Vol. 49 ( 6 ) page： 541-544 2002.6

Microstructural Characterizations of Pores and Grains for Specific Properties in P/M Soft Magnetic Materials Reviewed

T.Itoh, K.Kusaka and Y.Wanibe

Advances in Powder Metallurgy & Particulate Materials -2002, MPIF ( 14 ) page： 113-122 2002.6

Automotive PMSoftMagnetic Alloys (Relation between Magnetic Properties and Residual Pores in PM Soft Magnetic Alloys) Reviewed

J. Jpn Soc. Powder and Powder Metallurgy Vol. 49 ( 5 ) page： 430-437 2002.5

Quantitative Assessment of Pores to Reduce Variations in Component Characteristics Reviewed

Y.Wanibe,T. Itoh, S. Yokoyama and K. Kusaka

Advances in Powder Metallurgy & Particulate Materials -2001, MPIF ( 11 ) page： 1-9 2001.5

Quantitative Evaluation of Pores for Improvement in the Characteristics Properties of Soft Magnetic Materials Reviewed

Vol. 72 ( 2 ) page： 71-75 2001.2

Achievements in New Quantitative Approach to Powder Technology Invited Reviewed

Y.Wanibe and T.Itoh

Journal of the Japan Society of Powder and Powder Metallurgy Vol. 47 ( 12 ) page： 1291-1299 2000.12

Characterization of Pores for Specific Properties in P/M Soft Magnetic Materials Reviewed

T.Itoh, K.Kusaka and Y.Wanibe

Proceedings Powder Metallurgy World Congress & Exhibition 2000, Jpn. Soc. of Powder and Powder Metallurgy Vol. 2 page： 1364-1367 2000.12

Shape Separation of Powder Particles and Simulation Reviewed

T.Itoh and Y.Wanibe

Proceedings Powder Metallurgy World Congress & Exhibition 2000, Jpn. Soc. of Powder and Powder Metallurgy Vol. 1 page： 429-432 2000.11

Simulation for Estimation of Morphology of Projected Image from Sectioned Image of Iron Powder Particles Reviewed

T.Itoh and Y.Wanibe

Advances in Powder Metallurgy & Particulate Materials -2000, MPIF ( 1 ) page： 119-128 2000.6

Particle Shape Classification Useful for P/M Powders Reviewed

Journal of the Japan Society of Powder and Powder Metallurgy Vol. 46 ( 9 ) page： 914-920 1999.9

Measurement and Simulation of Morphological Characteristics on Projected and Sectioned Images of Iron Powder Particles Reviewed

T.Itoh and Y.Wanibe

Advances in Powder Metallurgy & Particulate Materials -1999, MPIF Vol. 12 page： 139-149 1999.6

Relationship between Compacting Behaviors and Morphological Characteristics for Metallic Powders Reviewed

T.Itoh and Y.Wanibe

Journal of the Japan Society of Powder and Powder Metallurgy Vol. 46 ( 1 ) page： 16 1999.1

Mutual Relation between Distributions Based on Number and Mass in The Particle Size-Shape Dispersion Diagram Reviewed

T.Itoh and Y.Wanibe

Journal of the Japan Society of Powder and Powder Metallurgy Vol. 45 ( 6 ) page： 574-580 1998.6

Qunatitative Analysis of Fluidity and Packing Based on Morphology of Powder Particles

Current Advances in Materials and Processes Vol. 10 ( 5 ) page： 1062-1066 1997.9

粉末プロセシングにおける定量評価

鰐部吉基, 伊藤孝至

鉄鋼の粉末冶金における新しい展開, 日本鉄鋼協会 page： 32-38 1997.9

Random Packing Simulation of Spheres and Practical Application for Real Powders Reviewed

T.Itoh and Y.Wanibe

Proceedings International Workshop on Modeling of Metal Powder Forming Processes page： 169-178 1997.7

Morphological Characterization of Iron Powders and The Estimating of Density Through Random Packing Simulation Reviewed

T. Itoh and Y. Wanibe

Advances in Powder Metallurgy & Particulate Materials -1996, MPIF Vol. 1 ( 4 ) page： 41-51 1996.6

The Effect of Particle Size Distribution of Metallic Powder on the Conductivity of Thermosetting Conductive Paste Reviewed

Journal of the Japan Society of Powder and Powder Metallurgy Vol. 42 ( 10 ) page： 1099-1102 1995.10

A New Method for Quantitative Analysis about Morphology(Size and Shape)of Inclusion in Metals

"Now Stand and Prospect on The Estimating Technique of Inclusion in Metals", The Japan Institute of Metals page： 28-31 1995.9

Analysis on Packed Mixtures of Short Fibers and Powders by their Characterized Specifics of Morphology Reviewed

T.Itoh, Y.Wanibe and K.kuroda

Journal of the Japan Society of Powder and Powder Metallurgy Vol. 42 ( 9 ) page： 992-997 1995.9

Application of new techniques for characterization of non-metallic inclusions in steel Reviewed

Y.Wanibe, T.Itoh, K.Umezawa, H.Nagahama and Y.Nuri

Steel Research Vol. 65 ( 4 ) page： 172-177 1995.4

Effect of Particle Characteristics on Fluidity of Metallic Powders (jointly authored) Reviewed

T.Itoh and Y.Wanibe

Journal of the Japan Society of Powder and Powder Metallurgy Vol. 41 ( 9 ) page： 1111-1116 1994.9

Characterization of Short Fibers and Packing Densities of Its Mixtures with Powders Reviewed

T.Itoh and Y.Wanibe

Advances in Powder Metallurgy & Particulate Materials -1994, MPIF Vol. 2 page： 113-126 1994.5

Quantitative Characterization in Powder Processing Reviewed

Vol. 65 ( 2 ) page： 135-144 1994.4

A Study on Quantitative Analysis in Powder and Powder Processing (jointly authored) Reviewed

T.Itoh and Y.Wanibe

Journal of the Japan Society of Powder and Powder Metallurgy Vol. 41 ( 3 ) page： 215 1994.3

New methodology for the determination of mass transport rate from rotating disks and/or cylinders in Liquid Reviewed

Y.Wanibe, E.Boschatzke, F.Oeters and T.Itoh

Steel Research Vol. 64 ( 2 ) page： 58 1994.2

Size Distributions Determined on Random Plane Sections of Non-Spherical Particles Reviewed

Y.Wanibe, T.Itoh, Y.Terada and T.Ohara

Journal of the Japan Society of Powder and Powder Metallurgy Vol. 40 ( 11 ) page： 1113-1116 1993.11

Shape Function of Non-Spherical Particles for the Determination of the Size Distributions from Measurements Made on the Random Plane Sections Reviewed

Y.Wanibe, T.Itoh, Y.Terada and T.Ohara

Journal of the Japan Society of Powder and Powder Metallurgy Vol. 40 ( 11 ) page： 1109-1112 1993.11

Comparison between the Size Distribution Determined on Random Plane Sections and Projected Shadows of Non-Spherical Particles Reviewed

Y.Wanibe, T.Itoh, Y.Terada and T.Ohara

Journal of the Japan Society of Powder and Powder Metallurgy Vol. 40 ( 11 ) page： 1117-1120 1993.11

Estimation of Density in Packed Beds of Non-Spherical Particles through New Modeling Reviewed

T.Itoh and Y.Wanibe

Proceedings 1993 Powder Metallurgy World Congress, Jpn. Soc. of Powder and Powder Metallurgy Vol. 1 page： 319-322 1993.7

Size Distribution of Non-Spherical Objects From Measurements Made on Random Plane Sections and of Projected Shadows Reviewed

Y.Wanibe and T.Itoh

Proceedings 1993 Powder Metallurgy World Congress, Jpn. Soc. of Powder and Powder Metallurgy Vol. 1 page： 1063-1066 1993.7

Analysis in Size Distribution of Non-Spherical Particles from Measurement Made on the Random Plane Sections

Y.Wanibe and T.Itoh

Vol. 11432 page：化II-1-19 1993.6

Quantitative Analysis in Heterogeneous Materials and Processing

Y.Wanibe and T.Itoh

Vol. 11323 page：反応-764 1992.5

Particle size-shape dispersion diagram and its application for the packing densities of metallic powders Reviewed

T.Itoh and Y.Wanibe

Preprints '5th European Symposium Particle Characterization' Vol. 2 page： 691-701 1992.3

Quantitative analysis in heterogeneous materials and processing Reviewed

Y.Wanibe and T.Itoh

Preprints '5th European Symposium Particle Characterization' Vol. 1 page： 243-257 1992.3

分散粒子の諸特性（粒度・形状及びそれらの分布幅）が粒子挙動（充填密度）に及ぼす影響量について

鰐部吉基, 伊藤孝至

日本学術振興会第19委員会資料 page：介在物-62 1992.2

Impact Atomization of Liquid Metals Reviewed

Y.Wanibe, T.Itoh and Y.Matsui

International Journal of Powder Metallurgy Vol. 27 ( 3 ) page： 195-209 1991.7

Particle Shape Distribution and Particle Size-Shape Dispersion Diagram Reviewed

T.Itoh and Y.Wanibe

Powder Metallurgy Vol. 34 ( 2 ) page： 126-134 1991.4

粒子形状分布と粒度－形状分散図

鰐部吉基, 伊藤孝至

日本学術振興会第19委員会資料 page：介在物-15 1990.11

Expansion during Liquid Phase Sintering of Iron-Copper Compacts Reviewed

Y.Wanibe, H.Yokoyama and T.Itoh

Powder Metallurgy Vol. 33 ( 1 ) page： 65- 69 1990.1

Quantative Analysis of Anisotropic Shrinkage during Sintering of Cylindrical Iron and Nickel Compacts Reviewed

Y.Wanibe, N.Fujitsuna, T.Itoh and H.Yokoyama

Powder Metallurgy Vol. 32 ( 3 ) page： 195-203 1989.7

Anisotropic Shrinkage and Thermal Expansion during Sintering of Cylindrical Nickel and Iron Compacts Reviewed

Y.Wanibe, N.Fujitsuna, T.Itoh and H.Yokoyama

Powder Metallurgy Vol. 32 ( 3 ) page： 191-194 1989.7

Simulation on Packing of Powders Invited

Vol. 5 ( 6 ) page： 65-69 1989.6

A Starting Point of Physical Chemistry in Powder Metallurgy -Characterization in Powder Processing- Invited

Journal of the Iron and Steel Institute of Japan Vol. 74 ( 8 ) page： 1526-1534 1988.8

Derivation of Number Based Size Distribution from Modified Mass Based Rosin-Rammler Distribution and Estimation of the Various Mean Particle Diameters Reviewed

T.Itoh and Y.Wanibe

Transactions of the Japan Institute of Metals Vol. 29 ( 8 ) page： 671-684 1988.8

Pulverization of Molten Sn and Sn-Cu by a Bladed Rotator Method Reviewed

T.Itoh, Y.Wanibe and K.Matsumoto

Transactions of the Iron and Steel Institute of Japan Vol. 28 ( 7 ) page： 561-568 1988.7

粉体プロセシングの物理化学における条件

坂尾　弘, 鰐部吉基, 伊藤孝至

日本学術振興会第19委員会資料 Vol. 10849 page：反応-664 1988.2

New Number Based Expression and Various Mean Particle Diameters for Rosin-Rammler Distribution Reviewed

Journal of the Japan Institute of Metals Vol. 51 ( 10 ) page： 956-964 1987.10

Infiltration of Molten FeO-SiO2 Slag into Pores in Al2O3-SiO2 Bricks with the Slagging Reaction Reviewed

Journal of the Iron Steel Institute of Japan Vol. 73 ( 3 ) page： 491-497 1987.3

Relation between Packing Density and Particle Size Distribution in Random Packing Models of Powders Reviewed

Journal of the Japan Institute of Metals Vol. 50 ( 8 ) page： 740-746 1986.8

Analysis of Packing Density by Randomly Packed Models of Binary Powders Reviewed

Journal of the Japan Institute of Metals Vol. 50 ( 5 ) page： 475-479 1986.5

Simulation of Random Packing Processes of the Powder with Forsfild's Size Distribution and Analysis of the Packing Cunfiguration Reviewed

Journal of the Japan Institute of Metals Vol. 50 ( 4 ) page： 423-429 1986.4

A Modified Rosin-Rammler Expression of Particle Distribution and the Interrelation between the Parameters of Mass and Number Bases Reviewed

Journal of the Japan Institute of Metals Vol. 49 ( 8 ) page： 670-677 1985.8

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