采用超音速火焰喷涂+大气等离子喷涂工艺,在 K403 高温合金表面制备不同层厚比的 NiCrAlY /纳米 7 YSZ 热障涂层,研究了涂层厚度变化对热障涂层表面粗糙度、结合强度、热震性能和热循环寿命的影响规律。 结果表明:当粘结层厚度一定时,随着陶瓷层厚度的增加,其表面粗糙度增加,涂层结合强度下降;当粘结层厚度为 50 μm 时,热障涂层的抗热震性能随陶瓷层厚度增加而降低,粘结层厚度提高至 100 μm 时,热障涂层的抗热震性能随陶瓷层厚度增加先提高,后降低,热障涂层在 1100 ℃ 的热循环寿命测试结果也基本对应这一规律;当粘结层厚 50 μm 且陶瓷层 / 粘结层的层厚比在(1 ~ 2 ) 颐 1 的范围内,或者粘结层厚 100 μm 且陶瓷层 / 粘结层的层厚比在(2 ~ 2 . 5 ) 颐 1 范围内时,热障涂层具有较优异的性能。

The NiCrAlY+7 YSZ thermal barrier coatings( TBCs) with various thickness were prepared by High Velocity Oxygen-Fuel Spray( HVOF) and Atmosphere Plasma Spray( APS) on the surface of K403 superalloy, the effect of thicknesses of coating on the surface roughness, bond strength, thermal shock resistance, thermal cycle life of TBCs were studied. The results show that surface roughness increases and bond strength decreases with thickness of ceramic coating increasing, when the thickness of bond coat is 50 μm, thermal shock resistance and thermal cycle life are decreased with thickness of ceramic coating increasing. When the thickness of bond coat is 100 μm, the thermal shock resistance of TBC increases first and then reduces with the increase of thickness of the top layer, at the same time the thermal cycle life test result of TBC is to corresponded to that rule at 1100 ℃ . Depend on these tests, confirmed TBC of NiCrAlY / nano-7 YSZ exhibites excellent performance,when the thickness of bond coat is 50 μm and 100 μm, the ratio of thickness with top coating / bond coat is 2 to 1 and 2. 5 to 2 respectively.