A study on the effect of the roller burnishing process on the axial fatigue performance and surface integrity of AISI 4340 steel

Abstract

In this study, the effect of the roller burnishing process on surface integrity and fatigue performance of AISI 4340 steel, which had been used in the cylinder of pressure intensifier, was investigated. The effects of burnishing depth, feed rate, and burnishing speed parameters of the roller burnishing process were examined. The roller burnishing process was applied to standard fatigue test specimens. After burnishing, surface roughness was measured, and fatigue life was determined by axial fatigue tests. The novelty of the study is the investigation of the axial fatigue performance of AISI 4340 steel at a specific stress ratio. Optimum levels of roller burnishing process parameters were determined for the lowest surface roughness and the highest fatigue life. The surface roughness was reduced from 2.98 to 0.51 mu m. It has been observed that the burnishing depth was the highest effect on the surface roughness at 78%. The most effective parameter on the fatigue life was the feed rate with a contribution ratio of 57%. Up to 70% improvement was obtained in the fatigue life of AISI 4340 steel.