Abstract: To improve the surface roughness and residual stress of engine blade for enhancing its working life and mechanical properties,the influence of process parameters on the roughness and residual stress was analyzed by single factor experiment combined with surface micro-morphology.The orthogonal test of the roughness and residual stress on the surface of the titanium alloy after polishing was designed.Based on the average grey relational distribution of grey system theory,the grey relational coefficient,the equal weight relational coefficient,the grey relational degree and the response weight were calculated and analyzed.Combined with the final optimal interval of sensitivity analysis,the results obtained by Equal weight optimization method and Grey relational optimization method were verified by experiment,and the effect of polishing was compared and analyzed.The results showed that the titanium alloy blade was polished by the optimal parameters of gray correlation model,which satisfied the requirements of the polished surface roughness of the blade while retaining a large residual stress.It proved that the grey correlation optimization method was more reliable and effective.

Key words: flexible polishing, surface integrity, sensitivity analysis, stability region, grey relational analysis

摘要： 为了改善发动机叶片的表面粗糙度与残余应力,以提高其工作寿命和机械性能,采用单因素实验结合表面微观形貌分析了各工艺参数对粗糙度与表面残余应力的影响规律;设计关于抛光后钛合金叶片表面粗糙度与残余应力的正交试验,结合单因素实验,分别建立粗糙度与残余应力预测模型,根据预测模型对粗糙度与残余应力进行敏感性分析并划分稳定域;通过灰色关联分析和等权关联分析建立优化模型;结合灵敏度分析所得的最终优选区间,对等权关联优化方法和灰色关联优化方法所得结果进行实验验证与对比分析,研究了两种优化方法所得工艺参数抛光叶片的残余应力随深度变化的规律。结果表明,采用灰色关联模型优化所得的最佳工艺参数对钛合金叶片进行抛光,在满足钛合金叶片抛光表面粗糙度要求的同时保留了较大的残余压应力,证明了该方法是可靠有效的。

关键词: 柔性抛光, 表面完整性, 敏感性分析, 稳定域, 灰色关联分析