混联机器人UD-CFRP铣削过程切削力及加工质量分析

Analysis of Cutting Force and Quality for Hybrid Robot in UD-CFRP Milling

随着碳纤维增强复合材料(Carbon fiber reinforced plastic,CFRP)在航空航天领域应用比例的增多,其切削加工也逐渐成为研究热点。基于TriMule混联机器人加工平台,通过螺旋立铣刀CFRP铣削实验,识别了不同切削条件下对应的切削力系数,发现CFRP铣削过程中的径向、切向切削力系数可以表示为纤维切削角的三角函数。结合不同切削参数的CFRP铣削实验对所提出的铣削力模型的准确性进行验证,分析了纤维切削角对CFRP铣槽加工质量的影响规律。在CFRP铣削加工中,毛刺按照其形成机理可以分为Ⅰ型和Ⅱ型两种,其中Ⅰ型毛刺由纤维在切削平面的弯曲变形引起,Ⅱ型毛刺由纤维在切削平面和垂直于切削平面的弯曲变形引起。试验结果表明,Ⅰ型毛刺长度随起始纤维切削角βs的增大而减小,Ⅱ型毛刺长度随截止纤维切削角βe的增大而增大。

With the increasing application of carbon fiber reinforced plastics(CFRP)in aircrafts,CFRP milling has become a research hotspot.A set of experiments in UD-CFRP milling for multiple helix tools has been carried out by using hybrid robot at different fiber angle,and the cutting force coefficients in tangential and radical directions are calculated.The results demonstrate that cutting force coefficients can be presented as a sine function of fiber cutting angle.The force model is capable of predicting cutting forces in the milling of CFRP with different process parameters.The effects of the fiber cutting angle on the milling surface quality of CFRP have been investigated.In the milling of CFRP,there are two different types of fiber burrs according to different deflection mechanisms of fiber,typeⅠand typeⅡ.TypeⅠfiber burrs are related to the bending of fiber in the laminate plane,typeⅡrelated to the bending of fiber in the laminate plane as well as perpendicular to the laminate plane.The results show that the length of typeⅠfiber burrs decreases with the increasing of initial fiber cutting angleβs,the length of typeⅡfiber burrs increases with increasing of final fiber cutting angleβe.