新型Nb-W-Ta合金高温自抗氧化失效分析

Failure Mode Analysis of Auto-antioxidation of New Nb-W-Ta Alloy at High Temperature

新型Nb-W-Ta合金及其涂层在新型冲压发动机结构件、液体火箭发动机等高温高强抗氧化材料需求方面有很好的前景。为保证其应用,必须在表面涂覆抗氧化涂层,以提高抗氧化能力,延长发动机寿命,通过实验分析其氧化失效模式,摸清合金自抗氧化能力上限,发现新型Nb-W-Ta合金在800℃开始出现氧化,温度升高自抗氧化能力逐渐减弱,高温下形成的氧化膜也更易剥落,若在高温下使用必须使用抗氧化涂层,两者协同才能达到效果。

The new Nb-W-Ta alloy and its coating have a good prospect in the fields of ramjet structural parts and liquid rocket engines for their demands for high temperature and high strength antioxidant materials.In order to ensure its application,it is necessary to coat the surface with antioxidation coating to enhance the antioxidation capacity and prolong the engine life.The oxidation failure mode of the new Nb-W-Ta alloy is analyzed through experiments to find out the upper limit of the auto-antioxidation capacity of the alloy.It is found that the oxidation of the new NB-W-TA alloy begins at 800℃,and the auto-antioxidation capacity gradually decreases as the temperature rising.The oxide film formed at high temperature is also easier to peel off.If it is used at high temperature,the antioxidation coating is necessary,only the synergy of them can make the it effective.