Surface improvement of shafts by the deep ball-burnishing technique

In this article, deep ball-burnishing as a mechanical surface treatment for improving productivity and quality of rotating shafts is presented. When this technique is combined and applied after conventional turning, the resulting process is rapid, simple and cost-effective, directly applicable in lathes and turning centers of production lines. rocess provides good surface finish, high compressive residual stresses, and hardness increment of the surface layer. These characteristics are the key for the fatigue life improvement of the component, and for wear resistance due to the higher hardness. ork presents a complete analysis of the principal beneficial aspects produced by the application of ball-burnishing. To determinate the influence of each process parameter, several tests were carried out. Once the optimum parameters were established, a complete analysis of the surface characteristics was performed. Surface topographies, sub-surface micro-hardness and residual stresses were measured. Complementary, a finite element model of ball-burnishing was used to understand and predict residual stress values and their variety with the process parameters. s show that burnishing is an economical and feasible mechanical treatment for the quality improvement of rotating components, not only in surface roughness but in compressive residual stresses as well.