The Effect of L-PBF Process Parameters on Surface Quality and Mechanical Properties of H13 Hot Work Tool Steel

Metal parts produced by Additive Manufacturing (AM) technologies typically suffer from poor surface quality, i.e. high surface roughness and porosity. Improving the surface quality could enable the manufacturing of components with little to no surface machining. In this research, we studied the effect of Laser Powder Bed Fusion (L-PBF) process parameters on the porosity and mechanical properties of H13 hot work tool steel. Optimized values for the core and border contour parameters were determined with a Design of Experiments approach using varying scanning speed, laser power and hatch distance parameters. The optimized process parameters were used to print samples for characterization. The experiments included microscopy analyses, surface roughness measurements and tensile testing. For comparison, some of the tensile specimens were machined to eliminate the effect of possible surface defects on the mechanical properties. The results suggest that a significant improvement in mechanical properties is achievable with optimized parameters.