著者

宇野 義幸

出版者

公益社団法人 精密工学会

雑誌

精密工学会誌 (ISSN:09120289)

巻号頁・発行日

vol.61, no.10, pp.1389-1392, 1995 (Released:2009-07-23)

参考文献数

5

被引用文献数

2 2

著者

玉置 司 植村 賢介 岡田 晃 宇野 義幸

出版者

公益社団法人 精密工学会

雑誌

精密工学会誌 (ISSN:09120289)

巻号頁・発行日

vol.78, no.1, pp.72-76, 2012-01-05 (Released:2012-07-05)

参考文献数

15

被引用文献数

3

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Plasma nitriding treatment is very effective for the hardening of precision metal parts. Especially, high density plasma nitriding can efficiently generate a high density ion with installed hollow cathode, which decreases the damage of the workpiece. As a result, the parts can be cleaned, etched, heated, and nitrided effectively. In this study, an improvement of surface integrity of stainless steel SUS440C is experimentally investigated by nitriding. The experimental analysis made it clear that the surface hardness of workpiece increased due to the generation of nitrided layer even under the low temperature condition like 513K. The nitrided layer was hardened with an increase of process temperature and process time, until a maximum surface hardness of 1700HV.

著者

宇野 義幸 金枝 敏明 横溝 精一

出版者

一般社団法人日本機械学会

雑誌

日本機械学會論文集. C編 (ISSN:03875024)

巻号頁・発行日

vol.59, no.566, pp.3199-3204, 1993-10-25

被引用文献数

5 6

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In this paper, we present the possibility of biological machining by bacteria as a new technique for metal removal. There are some kinds of chemolithotrophic bacteria which gain energy from inorganic matter and fix carbon dioxide of the air. Among them, there is a particular bacteria, Thiobacillus ferrooxidans, which "eats" metals. Machining of grooves on pure iron and pure copper by Thiobacillus ferrooxidans is experimentally investigated. The experimental analysis made it clear that biomachining was possible, since the depth of the groove generated on the workpiece increased approximately proportionally to the machining time. Furthermore, electric field assisted biomachining proved to be even more effective, because the removal rate became much higher under an electric field.