Porosity, Hardness, Friction and Wear Performance Analysis of H13 SLM-Formed Samples

Selective laser melting (SLM), a type of additive manufacturing, is a powder bed process that makes use of a high-power laser beam to completely melt a thin layer of powder on a substrate, layer upon layer to form a solid part. This experimental study confirmed that laser power and scanning speed are indeed SLM's most significant process parameters that affect porosity as stated in some literature and further studied the influence of laser power and/or laser-based volumetric energy density (VED) on hardness and friction and wear of SLM-formed samples. Full factorial design of experiment was carried out to study the influence of the two parameters on porosity with the help of Minitab 18 statistical software. The results obtained from this experiment were analyzed using analysis of variance. VED and laser power influence on hardness and friction and wear were studied on one factor at a time basis. Optimum laser power and scanning speed, optimum laser energy density values that achieve higher surface microhardness, minimum wear and porosity of H13 steel material were obtained from this experimental study.