钛合金表面电弧离子镀TiAlN涂层的抗高温氧化性能研究

Resislance to High-Temperature Oxidation of Are Ion PlatedTiAIN Coaling on Heat-Resisting Titanium Alloy

运用电弧离子镀技术,采用热等静压Ti0.5A l0.5合金靶在航空用钛合金TC11基片上制备了TiA lN防护涂层,并采用SEM、AES、XPS等方法研究了涂层在空气中的抗高温氧化性能。结果表明,涂层发生了选择性氧化,外层生成富A l层而内层形成富Ti层;同时进行了涂层的室温干摩擦试验,结果表明,TC11钛合金基体同GCr15钢珠的磨损表现出黏着磨损的特征,磨痕宽度约100μm,而TiA lN涂层通过提高表面硬度改善了钛合金的黏着磨损状况。

TiAIN coating was deposited on TC11 titanium alloy substrate by arc ion plating, using thermal isoslatic pressed Ti0.5A10.5 alloy an the target. The friction and wear behavior of the resulting TiAIN coaling sliding against GCrl5 steel hall at unlubricated conditions was evaluated. The oxidation resistance of the TiAIN coating al elevated temperature was investigated by means of scanning electron microscopy, Auger electron spectroscopv, and X-ray phnloetectron spectmacopy. lt was found that the TiAIN coating experienced selective oxidation as heated at 800℃ in air, with an Al-rich top layer and a Ti-rich inner layer to be generated during the oxidation process. At the same time, a compact layer of AI2O3 formed on the surface of the TiAIN coaling at elevated temperature was capable of closing the oxygen diffusion channels and henre slowing down the oxidation reaction. Moreover, the TiAIN coating contributed to increasing the hardness of the TC11 alloy and mitigating its adhesive wear againsl Gcr15 steel as well.