Finite element simulation of conventional and high speed machining of Ti6Al4V alloy

Abstract

Abstract Titanium alloys are known as difficult-to-machine materials, especially at higher cutting speeds, due to their several inherent properties and their high reactivity with cutting tools, which present a low thermal conductivity. In this paper a finite element analysis (FEA) of machining of TiAl6V4 both for conventional and high speed cutting regimes is presented. In particular, cutting force, chip morphology and segmentation are taken into account due to their predominant roles to determine machinability and tool wear during the machining of these alloys. In addition, taking into account that the considered process output are very sensitive to the material characterization, the Johnson–Cook's constitutive equation with three different sets of material constants (found by the application of several methods) is implemented in the FE model to study the behaviour of Ti6Al4V alloy during the machining process in conventional and high speed regimes. The comparison between the predicted chip morphology and principal cutting force at varying of high cutting speed regimes with those experimentally found are presented and discussed. The results indicated that a good prediction of both principal cutting force and chip morphology can be achieved only if the material constants for the Johnson–Cook's constitutive equation were identified using experimental data obtained by the methodology which permits to cover the ranges of true strain, strain rate and temperature similar to those reached in conventional and high speed machining.