The influence of hatch distance on the surface roughness, microhardness, residual stress, and density of inconel 625 specimens in the laser powder bed fusion process

Abstract

ABSTRACT The main goal of the laser powder bed fusion process is to produce high-quality parts with the required mechanical properties. Achieving this requires the proper selection of the key process parameters including laser power, scanning speed, layer thickness and hatch distance. In the present article, the effect of hatch distance parameter on the surface integrity issues i.e. surface roughness, residual stress, microhardness, and also density of Inconel 625 specimens has been studied using experimental approach. By using the non-destructive X-ray diffraction technique, residual stresses were measured in the different portion of the samples whose cross section changes. According to the results, as the hatch distance increases the microhardness decreases. The hatch distance has inverse effect on the residual stresses which its effect is less at the lower sections. It can be stated generally that the hatch distance increment reduces the microhardness, residual stress, and surface roughness but increases the specimen’s density.