Fundamental analysis of the cutting edge micro-geometry in orthogonal machining of unidirectional Carbon Fibre Reinforced Plastics(CFRP)

摘要

Machining of carbon fibre reinforced plastics(CFRP)is closely related to strong abrasive tool wear and represents a significant process challenge due to its anisotropic material structure and brittle fracture behavior Furthermore,machining of unidirectional CFRP material shows a significant increase in process forces due to tool wear effects,resulting in a changing micro-geometry of the cutting edge.This research work aims to give a detailed analysis of the tool wear behavior with respect to the five micro-geometry parameters based on an approach of”straight line-ellipse-straight line”,capable also to describe the developing asymmetric cutting edge.Therefore,fundamental orthogonal machining experiments with varying fibre orientations and tool geometries are conducted It can be shown that the micro-geometry changes with increasing cutting length,whereby an increase of the resulting friction length and spring back height can be detected,having a significant influence on the process forces.