最新色国产精品精品视频,中文字幕日韩一区二区不卡,亚洲有码转帖,夜夜躁日日躁狠狠久久av,中国凸偷窥xxxx自由视频

The virtues of the silicon nitride ceramic tools reinforced by transition metal nitride particles are compared with those of the carbides. It is found that the nitrides have better compatibility than the carbides when they are introduced into silicon nitride. Furthermore, because nitride particles can dissolve small amounts of carbon and oxygen, the carbonization of the silicon nitride matrix decreases, and hot pressing without an inert atmosphere is possible. In addition, electrical discharge machining and wear resistance are improved by the introduction of nitrides.