硬涂层对镍基高温合金叶片的振动特性影响

为了保障高温合金叶片在极端环境下安全工作，通常在叶片表面涂敷一层硬涂层以改善其抗冲刷和耐高温等性能。本文开展硬涂层高温合金叶片的振动特性研究，建立考虑涂层各向异性的叶片有限元模型。通过对叶片进行模态分析计算硬涂层叶片的固有频率，采用谐响应分析研究其振动位移响应，并绘制坎贝尔图进行共振特性分析，最终获得了硬涂层厚度及涂敷方式对高温合金叶片振动特性的影响规律。结果表明，硬涂层能够显著降低叶片响应峰值，最大达到36.8%；在叶片工作转速附近，共振点由3 个减为2 个。可见硬涂层对高温合金叶片具有明显的减振效果。

The effect of hard coating on vibration characteristics of nickel-based high-temperature alloy blades

In order to ensure the safe work of superalloy blades in extreme environment, a hard coating is usually applied to improve the performance of erosion resistance and high temperature resistance. In this paper, the vibration characteristics of hard-coating superalloy blades are studied, and the finite element models of blades considering anisotropy characteristics of coating are established. By modal analysis, the natural frequency of the hard-coating blade was calculated. The vibration displacement response was studied through harmonic response analysis, and the resonance characteristics were analyzed by drawing camber diagram. Finally, the influence of hard coating thickness and coating method on vibration characteristics of superalloy blade was obtained. The results show that the hard coating can significantly reduce the blade response peak value, up to 36.8%; and the number of resonance points is reduced from 3 to 2 near the blade working rotation speed. It can be found that the hard coating has obvious damping effect on the superalloy blade.