- 著者
- 宗藤 伸治 刑部 有紀 山外 啓太 岩永 純平 三浦 秀士 古君 修
- 出版者
- 一般社団法人 粉体粉末冶金協会
- 雑誌
- 粉体および粉末冶金 (ISSN:05328799)
- 巻号頁・発行日
- vol.64, no.8, pp.471-474, 2017-08-15 (Released:2017-08-31)
- 参考文献数
- 9
Poly-crystalline Ba8AuxSi46−x clathrate with p-n junction was synthesized for electric power generation from heat under no temperature difference. The n-type Ba8Au4.5Si41.5 and the p-type Ba8Au5.5Si40.5 powder were stacked in the graphite die and sintered by a Spark Plasma Sintering (SPS) method at 1073 K for 5 min with pressure of 50 MPa. The Au composition of Ba8Au4.5Si41.5 and Ba8Au5.5Si40.5 side in the sintered sample were Ba7.8Au4.2Si41.8 and Ba7.8Au5.2Si40.8, respectively. It was found that the Au composition was gradually changed near the interface with thickness of around 500 micrometers. Electric power generation test under no temperature difference was performed by using the sample cut to contain the interface of two layers. The electric power increased by only heating and the maximum voltage can be observed around 2 mV at 773 K. These results suggested that electron excitation occurred near the n/p interface and generated electrons and holes diffuse to n-type and p-type semiconductor side, respectively.
1 0 0 0 焼結低合金鋼の高性能化に向けたメゾヘテロ組織制御
- 著者
- 松田 光弘 三浦 秀士
- 出版者
- Japan Society of Powder and Powder Metallurgy
- 雑誌
- 粉体および粉末冶金 (ISSN:05328799)
- 巻号頁・発行日
- vol.47, no.6, pp.681-685, 2000-06-15
- 被引用文献数
- 3 7
In our previous studies on the 4600 steels produced by Metal Injection Molding (MIM) process using mixed elemental powder, the fine heterogeneous microstructure caused by the agglomeration of Ni powders was reported to be significantly effective for the improvement of mechanical properties. This study has been performed to clarify and optimize the relationship between the mechanical properties and the heterogeneous microstructure for ultrahigh strengthening the sintered low alloy steels (4600grade, 0.4 mass%C) produced by MIM process varying Ni content from 0 to 8 mass%.<BR>The tensile and fatigue strength were improved significantly with increasing Ni content to 6mass%, without loss of the ductility. This seemed to be due to the solution strengthening and the mezzo-heterogeneous microstructure which were consisted of Ni rich martensite surrounded by a network of tempered martensite. However, the tensile and fatigue strength of the steel added 8 mass% Ni were dropped by the increase of retained austenite.
1 0 0 0 OA 粉粒体利用ヘテロ組織ネット構造制御による機械構造用焼結合金鋼の超強靭化
粉末冶金によりヘテロ組織ネット構造を実現し,焼結合金鋼の超強靭化を図った.引張特性を調査し,最も引張特性に優れる最適な組成(6mass%Ni-0.4mass%C),焼結条件(1250℃×1h,真空)熱処理条件(960℃×30min溶体化後油焼入れ,200℃×1h焼戻し,Ar)を見出し,ヘテロ組織形態の最適化による超強靭な特性(最大引張強さ2040MPa,伸び8%)を得た.さらに,疲労強度は焼結鍛造鋼に匹敵する650MPaを示した.また組織観察の結果を有限要素法に反映してシミュレーションを行い,ヘテロ組織の優位性を確認した.