The Impact of Low Plasticity Burnishing Process Parameters on Residual Stress and Percentage of Cold Working Distribution in Ti-6Al-4V Alloy

Abstract

Compressive residual stress is a significant factor in influencing a fatigue failure of a mechanical component. In this perspective, the attempt has been made to induce beneficial compressive residual stress in Ti-6Al-4V alloy by using low plasticity burnishing process. The mechanism of LPB process includes rolling spherical balls made of tungsten carbide material over a material surface under fluid pressure supplied by a hydraulic unit. In this study, the cost-effective low plasticity burnishing tool with hydraulic fluid system is designed and fabricated. The LPB process was carried out on Ti-6Al-4V specimen with a suitable fixture. In this paper, the effect of burnishing process on residual stresses and cold working in Ti-6Al-4V was studied by using burnishing pressure and passes as a process parameter. The explicit module of the FE-Analysis code 6.17 was used with the aim of performing numerical simulation. The obtained experimentation results were considered to validate the results obtained by numerical FE analysis. It was found that there is good agreement between the experimental and numerical results. Both FEM simulation and experimentation results showed that hydraulic burnishing pressure is the most influential parameter in inducing beneficial compressive residual stress with less amount of coldwork.