Experimental Investigation And Optimization Of High Speed Machining Of Titanium Alloy For Biomedical Application

The Ti-6Al-4V alloy is known as materials with high hardness and good mechanical properties. However, the machining process of this material faces many difficulties due to unfavorable machining conditions. When the machining parameters are not selected in accordance with the Ti-6Al-4V alloy, the surface quality of workpieces does not meet technical requirements. Therefore, the appropriate machining parameters are needed to upgrade the surface roughness of workpieces in high-speed machining (HSM) conditions. The main cutting forces Py and Pz, and surface roughness Rz during turning of Ti-6Al-4V alloy in HSM were investigated and evaluated in this study. The response surface method (RSM) was used to conduct experiments and establish the models of Rz, Py, and Pz under various cutting conditions of feed rate (S), tool nose radius (R), and approach angle (φ). As a result, the S value has the largest impact on the Pz. Moreover, the machining parameters such as S, R, and φ have a great influence on the Py. The magnitude of Rz is mainly affected by R value. Based on the optimal parameters, the average value of the force Pz has decreased from 238N to 169N, corresponding reduction of about 29%. The value of the force Py has reduced from 184N to 118N, corresponding reduction of about 36%. In addition, the surface roughness of the workpiece has been improved significantly from Rz of 5.6 μm to 2.7 μm under optimal parameters condition. The surface roughness of the workpiece after processing in high speed machining was reduced of 52% compared with cutting under non-optimal parameters condition. The best surface quality and minimum cutting force could be achieved under optimal processing parameters in high speed cutting method.