The cavitation resistance of six kinds of austenitic metals was investigated using a rotating disc rig. The research results show that cavitation resistance of the austenitic metals is obviously raised due to cavitation-induced martensite and greatly influenced by mechanism of martensitic transformation. The cavitation resistance of two stress-induced martensite Fe-Mn-Si-Cr shape memory alloys is much better than that of three strain-induced martensite austenitic stainless steels. The Fe-Mn-Si-Cr shape memory alloys possess excellent cavitation resistance mainly because of their excellent elasticity in local small-zone. The first principal factor for cavitation resistance of metastable austenitic metals is unloaded rebounding depth, and the second one is energy dissipation resulted from cavitation-induced martensite.
在 Cu Ni Si B、 Ni Cr Si B自熔合金粉末中添加 WC陶瓷颗粒 ,利用氧乙炔焰粉末喷焊工艺制备覆层材料。用超声波振动气蚀仪对覆层材料进行耐气蚀性能研究 ,用扫描电子显微镜对覆层材料表面气蚀破坏形貌进行观察。结果表明 :复合覆层材料的耐气蚀能力比基体强 ;提高 Cu Ni Si B覆层材料耐气蚀能力的途径是强化晶界。
The variation in altitude density function (ADF) of the surface topography of mild steel during electrochemical polishing (ECP) was investigated, and the mechanism of the variation of surface roughness with polishing time was analyzed. The results show that the variation trend of ADF with polishing time is flat-steep-flat; the variation of surface roughness results in the different distri- butions of surface current density, and there is a fine surface smoothness in the special period of ECP from 4 to 8 s.