高速刮擦条件下封严涂层热物性对叶片损伤行为的影响

Effects of Thermal-physical Property of Seal Coatings on Blade Wear Behaviors Under High-speed Rubbing Condition

利用自制的高速刮擦试验机,对常见的铝、镍基封严涂层与TC4钛合叶片组成的封严摩擦副在高速刮擦条件下的摩擦学行为进行了研究。结果显示,铝基封严涂层对于叶片磨损轻微,甚至出现涂层粘着叶片的现象;镍基封严涂层严重的损伤叶片。通过分析刮擦面温度与力学性能变化间关系,发现封严涂层的热物性能对叶片的损伤具有重要的影响。若封严涂层的金属相熔点较低、热扩散率较大如铝基封严涂层,则配副使用时涂层易先于叶片发生软化,因而叶片磨损轻微,甚至被涂层粘附所代替。若封严涂层的金属相熔点较高、热扩散率较低如镍基封严涂层,则叶片易先于涂层发生软化,因而叶片损伤严重。

The tribological behaviors of seal friction pairs composed of commonly used aluminum-based and nickel-based seal coatings and TC4 titanium blades were studied under high-speed rubbing condition by a self-developed high-speed rubbing tester. The results showed that the aluminum-based seal coating causes slight damage to the blade and even adheres to the blade, while the nickel-based seal coating has serious damage to the blade. By establishing the relationship between the temperature of the rubbing interface and the mechanical properties, the thermal-physical properties of the seal coating are found to have great influence on blade wear. The coatings with low melting point and high thermal diffusivity such as aluminum-based coating tend to soften prior to the blade, so the blade wear is slight and even replaced by coating adhesion. If the coatings possess high melting point and low thermal diffusivity, such as nickel-based coatings, the blade rubbed before the coating was softened, and thus the blade suffered a severe damage.