枪速对热障涂层组织性能及残余应力的影响  

Effect of robot-scanning speed on microstructure,mechanical properties and residual stress of thermal barrier coatings

作　　者：李晨希[1] 刘爽[1] 张甲 常新春 

机构地区：[1]沈阳工业大学材料科学与工程学院,沈阳110870 [2]中科院金属研究所非平衡金属材料研究部,沈阳110016

出　　处：《沈阳工业大学学报》2015年第2期153-158,共6页Journal of Shenyang University of Technology

基　　金：国家自然科学基金资助项目(51171119)

摘　　要：为了研究等离子喷涂制备热障涂层(TBCs)时不同枪速对陶瓷面层组织性能和残余应力的影响,在GH4169高温合金基体上采用超音速火焰喷涂(HVOF)Ni Co Cr Al Y粘结层(BC层)和大气等离子喷涂(APS)8YSZ陶瓷层(TC层).通过对比不同参数样品的微观组织以及显微硬度、残余应力和热震性能差异,研究了枪速对热障涂层的影响.结果表明:枪速过低或过高时,涂层表面残余应力较大,热震性能较低;随着枪速的增大,涂层表面粗糙度逐渐增大,而孔隙率和显微硬度逐渐减小;枪速过低时,涂层出现纵向裂纹,热震失效方式为整体剥落;而枪速较大时,涂层从边缘向中心不断剥落,涂层表面出现白点.In order to study the influence of robot-scanning speed on the microstructure,mechanical properties and residual stress of thermal barrier coatings( TBCs) during the preparation of TBCs with the plasma spray method,the Ni Co Cr Al Y bond coating( BC) was sprayed with the high velocity oxygen fuel( HVOF)method and the 8YSZ ceramic coating( TC) was sprayed with the atmospheric plasma spray( APS) method on GH4169 superalloy substrate. Through comparing the differences in the microstructure,microhardness,residual stress and thermal shock performance of samples with different parameters, the influence of robot-scanning speed on the TBCs was determined. The experimental results showthat when the robot-scanning speed is too lowor too high,the residual stress on the surface of coatings is higher,and the thermal shock performance is lower. The surface roughness tends to increase with increasing the robot-scanning speed,while the porosity and microhardness gradually reduce. When the robot-scanning speed is too low,the vertical microcracks appear,and the thermal shock failure mode is whole spalling. When the robot-scanning speed is higher,the coating spalls from the edge to the center,and the white dots appear on the surface of coating.

关 键 词：大气等离子喷涂 超音速火焰喷涂 热障涂层 枪速 X射线 残余应力 显微硬度 热震性能 

分 类 号：TG174.4[金属学及工艺—金属表面处理]