电火花成型电极修整航空发动机叶片的加工误差分析  

Analysis of machining error of areo-engine blade trimmed by electrical discharge machining

作　　者：汪转延 蔡振辉 党宏伟 陈达源 曹利新[1] 余祖元[1] WANG Zhuanyan;CAI Zhenhui;DANG Hongwei;CHEN Dayuan;CAO Lixin;YU Zuyuan(School of Mechanical Engineering,Dalian University of Technology,Dalian 116024,China)

机构地区：[1]大连理工大学机械工程学院,大连116024

出　　处：《现代制造工程》2024年第3期95-102,共8页Modern Manufacturing Engineering

基　　金：国家自然科学基金项目(52275408);国家科技重大专项项目(2017-VII-0004-0097)。

摘　　要：针对航空发动机叶片电解加工后前后缘存在较大加工误差这一问题,采用电火花加工技术对叶片前后缘进行修整,并分析前后缘的加工误差。使用自研的六轴电火花成型机床,采用成型电极对叶片后缘进行修整加工,并利用三坐标测量机完成叶片点云数据的测量。采用遗传算法和迭代最近点算法,完成包络加工后叶片点云数据与理论模型的配准,通过最小二乘椭圆以及NURBS曲线拟合处理点云数据。针对拟合的叶片加工后轮廓曲线,通过在该曲线上等间距取点并计算这些点到叶片理论轮廓线的距离来反映叶片后缘的加工误差和加工误差的整体趋势。结果显示:经过电火花成型电极修整后叶片后缘的面轮廓度误差在-16.4~88.5μm之间,平均误差为53.7μm,叶片后缘的缘头处轮廓度误差最小,验证了电火花加工技术包络修整叶片前后缘的可行性。There is machining errors in the leading and trailing edges of aero-engine blade after Electrochemical Machining(ECM).Electric Discharge Machining(EDM)technology was proposed to trim the leading and trailing edges of blade to reduce machining errors,and then the machining errors of leading and trialing edges were analyzed.The self-developed six-axis EDM ma-chine was used to trim the trailing edges of blade by an electrode with curved surface.The point cloud data of blade surface was collected using a set of Coordinate Measuring Machine(CMM).The Genetic Algorithm(GA)and Iterative Closest Point(ICP)algorithm were used to register the blade point cloud data after envelope processing with the theoretical model of blade,and the least square ellipse and NURBS curve fitting were used to process the point cloud data.Aiming at the fitted blade contour curve after machining,the machining errors at the trailing edge of the blade and the overall trend of machining errors were reflec-ted by taking equidistant points on the curve and calculating the distance between these points and the theoretical contour of the blade.The results show that the profile error of the trailing edge of the blade is between-16.4~88.5μm,and the average error is 53.7μm.The profile error at the edge head of the trailing edge of the blade is the smallest,which verifies the feasibility of the EDM technology to cover the leading and trailing edges of the blade.

关 键 词：航空发动机叶片 前后缘 电火花加工 点云数据 NURBS 加工误差分析 

分 类 号：V232.4[航空宇航科学与技术—航空宇航推进理论与工程]