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

In this paper, the CrTiAlN coating was prepared by physical deposition technology on M2 high speed steel. The tribological behavior and surface morphology of the coatings were studied by means of emission scanning electron microscopy, energy dispersive spectroscopy, confocal scanning microscopy and ball-disc friction and wear testing machine. The results show that the friction coefficient of the coating increases with the increase of ambient temperature. At room temperature, the friction coefficient of the coating is about 0.24 and is gentle with time. At 200℃, the friction coefficient is greatly changed with time at beginning of Friction and then is stably about 0.53 at stable friction stage after half an hour. The wear rate of the CrTiAlN coating also increases with the increase of ambient temperature. The time variation curve of friction fluctuates greatly at high temperature and the wear degree of the grinding ball is gradually increased with the increase of temperature. The wear mechanism of the coating is mainly coordination role of oxidation wear, adhesive wear and abrasive wear.