Residual Stresses in Milled Beta-Annealed Ti6Al4V

Residual stresses can cause part distortion especially in the case of large components such as structural parts in aerospace industry. Therefore, this paper investigates the machining induced residual stresses for milling of a workpiece material with increasing usage in industry, the Beta-annealed titanium alloy Ti6Al4V. This thermal treatment results in a large grained material structure. For this reason X-ray diffraction, the standard residual stress measurement method, cannot be used for stress determination. In this paper an adopted indirect measurement method, the layer removal method is discussed. With respect to the material removal, two different methods are investigated, electrochemical material removal and laser ablation. Finally, the influence of the tool wear on the residual stress state after face milling is analyzed.