An analytical prediction model for residual stress distribution and plastic deformation depth in ultrasonic-assisted single ball burnishing process

Mechanical and metallurgical characteristics of the surface layers are modified as the material is subjected to the burnishing process. Plastic deformation is known as a major reason for property enhancement of the surface and subsurface layers. Residual stress distribution and influenced depth of plastic deformation provide useful information regarding the functionality and life cycles of the burnished sample. In the present study, a novel analytical approach was presented to predict residual stress distribution and the depth of plastic defamation in the ultrasonic-assisted ball burnishing process. The burnishing process was firstly analyzed using the contact mechanic of an elastic sphere with semi-infinite body theorem. Then, the plastic deformation and residual stress were modeled using the McDowell algorithm. The model could incorporate effects of vibration amplitude and frequency, static pressure, feed rate, and ball dimensions. A series of ultrasonic-assisted ball burnishing experiments have been carried out on aluminum 6061-T6 and AISI 1045 steel to confirm the proposed model prediction results. The prediction accuracy of the proposed model was further verified by residual stress distributions of AISI 304, Ti-6Al-4V, and Inconel 718 from other literatures. The research findings in this study indicated that the developed model could be used for a variety of engineering materials in the prediction of residual stress with adequate precision.