钛合金表面热喷涂NiCrAl涂层和热障涂层的氧化性能

Oxidation Behavior of Thermal Sprayed NiCrAl Coating and Thermal Barrier Coating on Titanium Alloy Surface

采用超音速等离子喷涂技术在TC4和Ti40钛合金表面制备NiCrAl及NiCrAl+ZrO2热障涂层,测定TC4、TC4+NiCrAl、TC4+NiCrAl+ZrO2、Ti40、Ti40+NiCrAl、Ti40+NiCrAl+ZrO2在600℃下的氧化动力曲线。通过扫描电镜(SEM)和能谱(EDS)分析研究钛合金、NiCrAl涂层和热障涂层组织形貌。结果表明:TC4在600℃的抗氧化性能优于Ti40;NiCrAl涂层与热障涂层能明显提高TC4和Ti40在600℃下的抗氧化性;600℃下氧化100h后,NiCrAl涂层、NiCrAl+ZrO2涂层与TC4界面处出现了扩散带和锯齿状的相,而与Ti40界面处只出现了扩散带,未发现锯齿状的相。

NiCrAl coating and NiCrAl+ZrO2 coating were sprayed on TC4 and Ti40 titanium surfaces by Supersonic Plasma Spraying method. The oxidation kinetic curves of TC4 alloy,NiCrAl coating on TC4,NiCrAl + ZrO2 coating on TC4,Ti40 alloy,NiCrAl coating on Ti40 and NiCrAl+ ZrO2 coating on Ti40 were obtained at 600 ℃. The microstructures of titanium alloy,NiCrAl coating and thermal barrier coating after oxidation were analyzed by SEM and EDS. The results show that TC4 alloy possesses good oxidation-resistance ability compared with Ti40 alloy at 600 ℃,the oxidation resistance of TC4 and Ti40 alloy is evidently improved by NiCrAl coating and thermal barrier coating at 600 ℃ and after oxidation at 600 ℃ for 100h,diffusing layer and indented phase exist in the interaction zones between coating and TC4 while only diffusing layer exists in the case of Ti40 without indented phase.