Influence of different cutting edges caused by tool wear on cutting process of titanium alloy TC21 based on finite element model

Abstract

Titanium alloys have emerged as a significant aerospace material due to the high strength, good corrosion resistance and high temperature resistance thereof, but such alloys also have poor machinability because of the unique properties. Rapid tool wear is a serious problem for titanium alloy machining, with tool wear resulting in different tool edges. In the present study, finite element technology was used to establish a 2D cutting numerical model, so as to investigate the influence of the different cutting edges caused by tool wear during the machining process of titanium alloy TC21. In the cutting model, four different types of tool edges, including sharp edge, round edge, chamfer edge and crater edge, were established to analyze the influence of different tool edges on the cutting process of TC21 alloy. Additionally, the material model, chip separation model, friction model and heat transfer model have been included in the established model. A series of cutting simulations based on the model were conducted, through which the chip morphology, cutting temperature, cutting force, surface morphology and residual stress under the different tool edges were analyzed. The simulation results were compared with the experimental results, and indicated that the tool edge is a significant factor in the machining process of TC21 alloy. A proper cutting edge can improve the cutting quality.