铂改性铝化物涂层的高温防护性能研究

摘要

Objective To investigate the anti-oxidation behavior of Pt modified aluminide (Pt-Al) coatings at 1100℃.Me-thods Pt modified aluminide (Pt-Al) coatings were fabricated by chemical vapor deposition (CVD) on the single crystal supe-ralloy substrates .The phase structures, morphologies and composition of the Pt-Al coatings after oxidation were analyzed by XRD, SEM and EDS in detail.Results The results indicated that the oxidation kinetics curves of the coatings were in accor-dance with parabolic rule after oxidation at 1100℃ for 250 h. The performance of oxidation resistance of the single crystal superalloy was more significantly improved by the deposition of Pt-Al coatings than Al coatings. The oxide scales on top of the coatings’ surface peeled off after 150 h oxidation, meanwhile, "cunculus" occurred inside the coating.Conclusion Pt-Al coating largely improved the oxidation resistance of the substrates at high temperatures.%目的：研究1100℃下铂改性铝化物（Pt-Al）涂层在空气中的高温氧化行为。方法采用化学气相沉积（CVD）方法在单晶高温合金基体上制备铂改性铝化物（Pt-Al）涂层，采用X-射线衍射（XRD）、扫描电子显微镜（SEM）、能谱仪（EDS）等方法分析Pt-Al涂层在高温氧化过程中相结构、显微组织和成分的演变规律。结果经1100℃氧化250 h后，Al涂层及Pt-Al涂层的氧化动力学曲线符合抛物线演变规律，Pt-Al涂层的涂覆对基体合金的抗高温氧化性能的提高要优于Al涂层；经过150 h氧化后涂层出现了氧化膜剥落现象，同时涂层内部也出现了“地道”现象。结论 Pt-Al涂层对基体高温抗氧化性能有积极效果。