Al_(2)O_(3)膜对高温环境下NiCrAlY-SiC复合镀层内部反应的阻隔及涂层耐磨性研究

Study on the abstruction effect of Al_(2)O_(3)film against the internal reaction of NiCrAlY-SiC composite coating in high temperature environment and the wear resistance of the coating

为了解决以SiC颗粒为磨料的叶尖耐磨复合镀层在高温工况下SiC与涂层中Ni元素反应导致涂层耐磨性下降等问题,采用化学气相沉积(chemicalvapor deposition,CVD)工艺方法在SiC颗粒表面制备了Al_(2)O_(3)膜以阻隔SiC与涂层中Ni元素的反应。研究了0.5~1.0μm和5.0~10.0μm这2种厚度范围的Al_(2)O_(3)膜对NiCrAlY-SiC@Al_(2)O_(3)叶尖耐磨镀层中SiC颗粒与NiCrAlY镀层在1100℃高温环境下反应的阻隔效果,并测试了2种Al_(2)O_(3)膜厚度的NiCrAlY-SiC@Al_(2)O_(3)叶尖耐磨镀层在1100℃高温环境下保温500 h后的耐磨性。结果显示,5.0~10.0μm厚度的Al_(2)O_(3)膜可有效阻隔SiC颗粒与NiCrAlY镀层的高温反应,使NiCrAlY-SiC@Al_(2)O_(3)涂层在1100℃高温环境下保持良好的耐磨性,并与ZrO2陶瓷封严涂层形成良好的对磨匹配效果。

In order to solve the problem related to the reaction of SiC particles with Ni element in the abrasive blade tip coating pre⁃pared by composite electroplating under high temperature conditions and the resulting decrease in the wear resistance,Al_(2)O_(3) films were coated on the surface of SiC particles by chemical vapor deposition(CVD)process to block the reaction between SiC and Ni.The barrier effect of Al_(2)O_(3) films with two thickness ranges of 0.5-1.0μm and 5.0-10.0μm on the reaction between SiC and NiCrAlY in NiCrAlY-SiC@Al_(2)O_(3) abrasive blade tip electroplated coating at high temperature environment of 1100℃was studied,and the wear resistance of NiCrAlY-SiC@Al_(2)O_(3) abrasive blade tip electroplated coating with two different Al_(2)O_(3) film thickness was also tested after being kept at 1100℃ for 500 h.The results show that Al_(2)O_(3) film with a thickness of 5.0-10.0μm can effectively block the high temperature reaction between SiC particles and NiCrAlY coating.It helps NiCrAlY-SiC@Al_(2)O_(3) coating maintain good wear resistance under 1100℃ high temperature environment and form a good wear matching effect with the ZrO2 ceramic seal coating.