Enhanced mechanical properties of Ti-6Al-4V titanium alloy through laser-assisted burnishing

Abstract The surface modification of titanium alloys, specifically Ti-6Al-4V, is a critical procedure that significantly augments the material's surface integrity and mechanical properties. This process is of paramount importance in various industries, including aerospace, medical, and automotive sectors. This research introduces a novel method, termed Laser-Assisted Burnishing (LAB), which is engineered to enhance the surface integrity of Ti-6Al-4V. The LAB process parameters, encompassing burnishing temperature, speed, feed rate, force, and number of passes, were meticulously optimized to ameliorate surface characteristics. A comprehensive experimental investigations was undertaken to study the surface generation of LAB-treated Ti-6Al-4V, and the results were systematically analyzed. Key performance indicators such as surface roughness, microhardness, and residual stresses were evaluated under LAB conditions and compared with those obtained via traditional burnishing methods. The LAB process yielded a reduction in surface roughness (Ra) to 0.364µm, an increase in microhardness from 324.4 to 464.8 HV, and notable enhancement in the thickness of hardened layer and compressive residual stress. These results validate the effectiveness of the LAB technique in improving the surface integrity of the Ti–6Al–4V alloy. The primary contributing factor to this enhancement is the augmented plastic deformation facilitated by the transient material softening during LAB process.