The thermal barrier coating by taking MCrAlY as bonding coating and ZrO2 + 8% Y2O3 as top coating were deposited on the nickel-based super-alloy by air plasma spraying. Pre-oxidation treatment was carried out on the thermal barrier coatings by controlling the oxygen pressure in high vacuum sintering furnace. Then, the effects of pre-oxidation treatment on the thermal shock resistance and residual stress were investigated, respectively. The results show that pre-oxidation treatment improves the density of bonding coating, which makes it uniform and reduces the probability of complex stress caused by convex point in interface area. Meanwhile, pre-oxidation treatment interferes the growth process of thermally grown oxide (TGO) , reduces the TGO growth rate and the stress concentration of coating. Residual stress increases with the increasing of thermal cycles. However, pre-oxidation treatment can slow down the increasing rate of residual stress. The residual stress of 650.1 MPa can be reached after 350 thermal cycles without pre-oxidation, while the residual stress is only 492.5 MPa after 400 thermal cycles with pre-oxidation.%采用等离子喷涂工艺在镍基高温合金基体上制备了热障涂层(底层为MCrAlY,面层为ZrO2+ 8％ Y2O3),通过控制高真空烧结炉的氧分压对涂层进行预氧化处理,分析了预氧化处理对热障涂层热冲击性能和涂层应力状态的影响.结果表明,预氧化处理提高了粘接层的致密度,涂层组织变得均质化,降低了粘结层由于凸起尖角产生复杂应力的概率；有效干预热生长氧化物(TGO)的生长过程,降低了TGO的生长速度；热障涂层残余应力随热冲击次数的增加而增大,但经过预氧化处理的涂层应力增长幅度较缓慢,经过400次热冲击后的残余应力为492.5 MPa,未经过预氧化处理涂层热冲击350次后应力值为650.1 MPa.
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