作　　者： ; ; ; ; ;

机构地区： 福州大学材料科学与工程学院

出　　处： 《热加工工艺》 2007年第3期53-56,共4页

摘　　要： 运用扫描电镜和台阶仪研究了在不同状态下的1Cr18Ni9Ti不锈钢和纯Cu基底上大气等离子喷涂Mo层片的形成机制。结果表明:室温光滑基底上沉积的Mo层片均呈不规则飞溅花瓣状,随预热温度升高,形成的层片逐渐变得较完整;熔滴撞击铺展过程中在基底上可能会形成凹坑;基底导热率越高,层片铺展度越小;粗糙基底表面阻碍熔滴铺展,促进熔体飞溅。理论分析表明,"花瓣状"层片的形成是熔体表面张力、熔体与基底接触热阻的不均匀性和基底凹坑相互作用的结果;基底凹坑的形成主要由基底熔化所控制。 The formation mechanisms of plasma sprayed Molybdenum splats on 1Cr18Ni9Ti stainless steel and pure copper under different states were investigated by SEM and surface profiler. The results indicate that Mo splats which are deposited on all the smooth substrates at room temperature take on irregular flower-like shape, with the increase of preheating temperature, the morphologies of the splats change from splashing to more integrated. Craters are formed possibly on the substrate during the drop impacting and spreading. The higher the thermal conductivity of substrate is, the smaller the flattening degree of splat will be. The flattening of impinging drop is blocked by rough substrate surface, and the splashing is promoted. Theoretical＂ analysis reveals that the formation of flower-like splats results from the interaction of surface tension, inhomogeneity of thermal contact resistance between flattening drop and substrate and substrate crater. The formation of the craters on the substrate is mainly controlled by substrate melting.

关 键 词： 等离子喷涂 层片 基底 形成机制

领　　域： [金属学及工艺] [金属学及工艺]