SURFACE RESIDUAL STRESS OF TITANIUM ALLOY INDUCED BY MILLING

The residual stress is very important parameter,which causes the deformation,fatigue issues of parts. However,it may be controlled in machining by selecting the right cutting parameters. In this study,the aim is to investigate the effects of various milling parameters on the surface residual stress of workpiece when machining of Titanium alloys Ti6Al4V. The residual stresses in both speed and feed direction were measured using the X-ray diffraction method. The Psi-oscillation,Phi-oscillation and peak fit method were adopted in X-ray measurement to ensure a satisfied precision. It is found that,the residual stress is a compressive value for the down milling of Titanium alloy Ti6Al4V,which is mainly due to the strong burnishing effect between the tools flank face and the machined surface. In cutting direction and feed directions,the effects of cutting parameters on residual stress are various. It is possible to generate customized stress in the product by controlling the cutting parameters such as cutting speed,feed speed and axial depth etc.