Pd-Ni-Al涂层的抗高温循环氧化性能

Cyclic Oxidation Behavior of Pd-Ni-Al Coating

在IN738镍基高温合金上,采用低压固体粉末包埋渗铝方法制备钯改性铝化物涂层。利用TGA、XRD、SEM以及金相等方法,研究了Pd-Ni-Al涂层在1 050℃的高温氧化行为。结果表明:与NiAl涂层相比,Pd-Ni-Al涂层表面氧化膜粘附性优良,改性涂层的退化相 远少于普通NiAl涂层,显示出优良的高温稳定性。添加改性元素Pd,提高了铝化物涂层的抗循环氧化性能。

Palladium-modified aluminide coatings were prepared by low-pressure pack cementation on the nickel-base superalloy IN738, and their cyclic oxidation behavior was investigated by TGA, XRD, and SEM at 1 050degreesC. Results show that the Pd-Ni-Al coatings have more adhesion than the simple aluminide coatings, and that the microstructural degradation of the Pd-Ni-Al coating is slower than that of the simple aluminide coating. The palladium plays a significant role in alumina stabilization and in delaying the degradation of beta-phase. Key words: Pd-Ni-Al coating; aluminide coating; cyclic oxidation; palladium