Influence of process parameters on surface quality of CoCrMo produced by selective laser melting

Abstract

Nowadays, selective laser melting (SLM) technology features is somehow unknown mainly on the process parameters needed for each material. The main goal of this work is to give better process parameters combination when CoCrMo powders are utilized. A statistical methodology based on the experimentation has been applied. In this study, a full factorial design is used. It assesses the impact of process parameters on surface quality (Q), flatness, overlapping, and surface roughness. The distinguishing feature is the melting of single layers in variable layers powder with a continuous laser. Based on these results combined with visual observation of the solidified tracks, the effect of process parameters on the surface roughness for each case is investigated. The results show that surface roughness (Ramax) is affected strongly by laser power, scan spacing, and scanning speed thereby giving an average roughness at 8 μm. In addition, other roughness parameters such as the peak height (Rp) and depth of the lowest point of the profile (Rv) are found to be useful tools for evaluation of top quality. The best layers have been showed when the laser powers are 300 and 400 W and the scanning space of 450 and 600 μm. These layers are classified with (Q) less than 2.