高速微粒轰击对热障涂层热生长氧化物生长过程的影响

Effect of high-speed fine particles bombarding on thermally grown oxide growth process of thermal barrier coatings

研究了高速微粒轰击NiCoCrAlY粘结层后的热障涂层热生长氧化物(TGO)的生长过程。结果表明:等离子喷涂涂层1050℃×72h高温氧化后TGO出现明显分层现象,而经过高速微粒轰击涂层1050℃×96h高温氧化后TGO形貌更为平坦且无分层现象发生。此外,NiCoCrAlY粘结层经高速微粒轰击后产生大量的位错网;TGO进入稳态氧化阶段时间缩短,稳态氧化阶段时间延长。涂层抗高温氧化性能明显提高。

Growth process of thermally grown oxide （TGO） for NiCoCrAIY bond coating after high-speed fine particles bombarding was studied. It is shown that the apparent lamination forms in TGO for as-sprayed coating after oxidation at 1050℃ for 72h. However, no lamination in TGO is observed for the high-speed fine particles bombarded coatings after oxidation at 1050℃ for 96h. Furthermore, high density dislocation nets form in the NiCoCrAIY bond coating after high-speed fine particles bombarding, and the time for TGO coming into steady-state oxidation stage is shortened and the period of steady-state oxidation becomes longer. The high-temperature oxidation resistance of the thermal barrier coatings prepared on the bombarded NiCoCrAIY bond coating is improved obviously.