Analysis of tool wear performance and surface quality in post milling of additive manufactured 316L stainless steel

Laser additive manufacturing (LAM) technology applied to the 316L stainless steel is attracting interest in the machining industry since it can shorten the production cycle and reduce numbers of machining steps. It still needs to be machined because of the poor surface quality, so the tool wear of post milling process after LAM needs to be studied. However, there are a few studies about the tool wear in milling of laser additive manufacturing stainless steel alloy. The aim of the paper is to evaluate the tool wear performance and surface quality when post milling the 316L stainless steel under different post milling (PM) time. The tool wear behavior was investigated using different analysis techniques. 3-D surface contour profilometer was used to measure the surface roughness and observe the morphology of small area; digital optical ultra-depth microscope analysis was carried out to evaluate tool wear and broken; the wear width of the blade was an indicator of the degree of the tool wear; different post milling methods were also compared. The obtained results demonstrate that the height of the LAM parts were connected with the heat dissipation effect; there are three stages of tool wear: initial wear stage, normal processing stage, and severe broken stage; usually the down-milling is better than up-milling at the bottom surface roughness, quality and edge morphology.