著者
吉原 一紘 新居 和嘉
出版者
公益社団法人 日本金属学会
雑誌
日本金属学会誌 (ISSN:00214876)
巻号頁・発行日
vol.47, no.11, pp.941-949, 1983 (Released:2008-04-04)
参考文献数
12
被引用文献数
4 2

The surface composition of 18-8 stainless steel doped with boron and nitrogen at high temperatures was observed in vacuum with AES and XPS.The precipitation of boron nitride was found on the surface of the stainless steel. At the first stage of heating, a thin layer of boron nitride flowed out from grain boundaries and spread on the surface, replacing phosphorus and sulfur which segregated all over the surface. As the heating time was prolonged, parts of the thin layer of boron nitride increased in thickness. The thickness increased in proportion to the square root of heating time and became about 0.06 μm after heated at 1100 K for 432 ks. The precipitated boron nitride was not replaced by the most surface active element, sulfur, and remained stable on the surface. On the surface of the stainless steel, however, there existed areas not covered with boron nitride after prolonged heating. On these uncovered areas, sulfur segregated.The precipitated boron nitride layer was inert to the adsorption of gases. Therefore, this stainless steel is a superior candidate material for vacuum vessels.