Effect of abrasive grains size on surface integrity during belt finishing of a 27MnCr5 carburized steel

Abstract

Belt finishing is a superfinishing process that enables to reach fine surface integrity properties, i.e. low surface roughness and compressive residual stresses in the external layer. Among the wide range of process parameters, belt grain size has a dominant influence on surface roughness. However the effect on residual stresses is rarely studied. This paper investigates the effect of a wide range of belt grain sizes on surface integrity (both surface roughness and residual stresses) generated during belt finishing. The study focuses on cylindrical shafts made of a carburized 27MnCr5 steel. The results show that the grain size has no clear effect on residual stresses. Furthermore, a too low grain size will induce a low material removal rate and the final surface signature will be difficult to reach under a reasonable process time (acceptable for mass production). Therefore, this experimental work highlights that an optimal grain size (around 20-30 μm) exists for a defined initial surface roughness and a process duration.