利用自制空化水射流设备对纯铜进行了不同时间的冲蚀,研究了冲蚀后试样的显微组织、损伤形貌、表面粗糙度以及截面硬度,分析了空蚀损伤过程及机制.结果表明:一次射流区空蚀坑底部晶粒弯曲变形,而混合射流区的截面组织无明显变化;一次射流区在水射流冲蚀5 min时,表面就已经出现空蚀坑、空蚀针孔,随冲蚀时间的延长,空蚀坑和空蚀针孔数量增多,晶粒形貌逐步显现,同时出现大量的变形滑移带和金属剥落现象;混合射流区的空蚀坑大而浅,且随着时间的延长整个晶粒形貌全部显现;空蚀坑是以空蚀针孔聚集导致少量金属剥落这种形式长大的;随冲蚀时间的延长,两区的表面粗糙度逐渐上升,且混合射流区的表面粗糙度大于一次射流区的,其硬化层厚度和近表层硬度也相对较大.%Cavitating water jet erosion was carried out on pure copper for different times by a self-made cavitating water jet device.The microstructure, damage morphology, surface roughness and cross section hardness of the specimens after erosion were studied and the cavitation damage process and mechanism were also analyzed.The results show that the bending deformation of grains occurred in the direct water jet zone while the cross section microstructure in the mixed water jet zone remained unchanged.After water jet erosion for 5 min, some cavitation pits and needle-like cavitation pits appeared in the direct water jet zone.With the increase of erosion time, the amounts of cavitation pits and needle-like cavitation pits increased and the grain morphology appeared gradually.Meanwhile a large amount of deformation slip bands and metal spalling phenomena were also observed.In the mixed water jet zone, cavitation pits were large and shallow and grain morphology emerged entirely with time increasing.The needle-like cavitation pits around gathered and led to a small number of metal spalling, which was the reason why the cavitation pit became larger and larger.With the increase of erosion time, the surface roughness of the two zones increased gradually, and the surface roughness of the mixed water jet zone was larger than that of the direct water jet zone, so were the hardening layer thickness and near surface hardness.
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