【摘要】 采用扫描电镜及能谱对航空发动机涡轮叶片热障涂层进行失效分析,将叶片划分为9个区域,发现其前缘区域由于涂层的使用温度高、粘结层氧化、尖晶石等大量生长,导致在TGO/陶瓷层界面处产生大量的生长应力,呈TGO/Top coat界面分层失效。后缘区域呈粘结层/基体分层分裂失效,同时所有区域都有CMAS腐蚀。CMAS附着在涂层表面,沿着纵向裂纹等缺陷渗透到涂层内部,引发涂层产生横向分层,并导致涂层腐蚀剥落。更多还原

【Abstract】 The failure behaviors of thermal barrier coatings deposited on turbine blades were studied. The blades were divided into 9 areas and the microstructure and composition of coatings were investigated by scanning electron microscopy( SEM) and energy dispersive spectrometer( EDS). It was found that the trailing edge area presented the interfacial cracking of bond coating and substrate because of oxidation of bonding layer and the occurrence of a large amount of spinelle resulting from higher service temperature. However,the leading edge area presented the delamination of TGO/top coat interface. CMAS deposits were observed in all samples. CMAS adhered to the surface of the coating,and infiltrated into the interior of the coating along the longitudinal cracks and pores,which led to the delamination of the coating and exfoliation of the coating.更多还原