Experimental investigation on the effect of barrel finishing processes on surface integrity of 18CrNiMo7-6 carburized rollers

Abstract

There has been growing interest in enhancing the properties of machine components to improve their reliability in recent years. Surface barrel finishing is one of the most widely used surface processes to decrease the surface roughness of components and improve mechanical properties. However, the effect of barrel finishing parameters on surface integrity such as residual stress and hardness distribution is still unclear, which needs an in-depth understanding. This study experimentally investigated the effect of different barrel finishing media and finishing time on the surface integrity including surface morphology, residual stress, microhardness and microstructure of 18CrNiMo7-6 carburized rollers. Experiment results demonstrate that the surface roughness Sa can be decreased to less than 0.2 μm with the surface barrel finishing, and the surface compressive residual stress (SCRS) can be increased by 500 MPa compared with shot peening process. In addition, the surface microhardness increased by 20 HV and the grain size of the surface layer was refined. The improvement of the surface integrity should be of interest for engineers when designing against rolling contact fatigue.

A modified model of Lundberg-Palmgren rolling contact fatigue formula considering the effects of surface treatments

“…The residual stress at each material point was tested 3 times, and those values were averaged as the final residual stress. Since the values of the axial residual stress and hoop residual stress of SP, FPP, and SF are not very different [22][23][24], only the axial residual stress gradients are given in Fig. 4(a).…”

The effect of fine particle peening on aviation gear performance, part II: Rolling contact fatigue

“…1 These technologies include surface coating, 2 shot peening, 3,4 and barrel finishing. 5 To achieve significant improvements in rolling contact fatigue performance of gear, it is essential to have a comprehensive understanding of the effects of surface integrity on their fatigue resistance after strengthening processes. 6,7 One of the critical factors in the design of fatigue-resistant gears is the hardness gradient, as it can serve as an indicator of a component's ability to withstand deformation and damage.…”

“…In engineering, various surface strengthening technologies are commonly employed to improve the surface integrity of gears and enhance their rolling contact fatigue performance 1 . These technologies include surface coating, 2 shot peening, 3,4 and barrel finishing 5 …”

The effect of fine particle peening on aviation gear performance, Part I: Surface integrity

“…[9][10][11] Another common surface strengthening method, barrel finishing technology, can effectively reduce surface roughness, but it has little influence on residual stress and surface hardness, and its processing efficiency is limited. 4,12 Therefore, these technologies are not well suited for surface strengthening of precision aviation gears.…”

“…In engineering, surface strengthening technologies, such as coating, 2 shot peening, 3 and barrel finishing 4 are commonly employed to improve the surface integrity of the gear, and then enhance the rolling contact fatigue performance of the gear. Shot peening is one of the most utilized surface‐strengthening techniques and has been used extensively in numerous industries.…”