GH4169铣削残余应力研究及工艺参数优化

Research on residual stress in milling GH4169 and parameters optimization

GH4169材料在航空、航天热端部件的制造中应用较多,为了改善GH4169材料的工件疲劳寿命、提高加工效率,文章设计了GH4169铣削工艺参数与工件表面残余应力之间的正交试验。通过试验,建立了铣削参数与铣削表面残余应力之间的经验公式,分析了铣削参数对铣削表面残余应力的影响规律。另外,应用遗传算法,以铣削表面残余应力、材料切除率的期望值为优化目标,对铣削参数进行了多目标优化,并对优化结果进行了试验验证。结果表明:切削速度对X、Y向残余应力的影响是最主要的,每齿进给量对于X向残余应力的影响次之,对于Y向残余应力的影响最小;切削深度对于X向残余应力的影响最小,对于Y向残余应力的影响次之;较小的切削速度和较大的每齿进给量有利于获得期望的表面残余应力,切削深度的变化对残余应力的影响较小;优化的铣削参数组合为:v_(c)=26.64 m/min,a_(p)=0.45 mm,f_(z)=0.10 mm/z,a_(e)=0.25 mm,可以降低GH4169材料表面残余拉应力,提高切削效率,为GH4169零件铣削参数的选取提供依据。

GH4169 was widely used in the manufacturing of aerospace hot end components.In order to improve the fatigue life of GH4169 workpieces and improve machining efficiency,an orthogonal experiment was designed between milling parameters and residual stress on the surface of the workpiece.Based on experiments,an empirical formula was established between milling parameters and surface residual stress,and the influence of milling parameters on surface residual stress was analyzed.In addition,genetic algorithm was applied to optimize the milling parameters with the expected values of surface residual stress and material removal rate as the optimization objectives.And the optimization results were experimentally verified.The results indicated that the cutting speed had the greatest impact on the residual stress in the X and Y directions.The influence of feed rate per tooth on the residual stress in the X direction was second,and the influence on the residual stress in the Y direction was the smallest.The influence of cutting depth on the residual stress in the X direction was the smallest,and the influence on the residual stress in the Y direction was the second.A smaller cutting speed and a larger feed rate per tooth were beneficial for obtaining the desired surface residual stress,and changes in cutting depth have a little impact on residual stress.The optimized milling parameter combination was:v_(c)=26.64 m/min,a_(p)=0.45 mm,f_(z)=0.10 mm/z,a_(e)=0.25 mm,The optimized milling parameters can reduce the residualstress on the surface of GH4169 material and improve cutting efficiency.It can provide a basis for the selection of milling parameters for GH4169 parts.