Additive manufacturing of H13 tool steel

Abstract

In the additive manufacturing process named Selective Laser Melting (SLM) a part is built layer by layer. A laser selectively melts layers of powder that are placed successively, being able to obtain parts with complex shapes and customized densities. The first step during SLM is to optimize the process parameters in order to produce parts with a high relative density and free of defects as porosity and cracks. Every combination of machine and powder presents its own optimum parameters set. This project aims to perform this optimization step for the commercial H13 tool steel, which will be used to fabricate polymer injection molds during the Thematic FAPESP Project "THE STUDY, DEVELOPMENT AND APPLICATION OF A HYBRID PROCESS: Additive Manufacturing (AM) plus High Speed Machining/Grinding (HSM/G)". Samples of H13 steel with geometry of 10x10x5 mm will be produced using different hatchings, laser power, laser scanning speeds and scanning strategies. The density of these samples will be measured and those with higher density will be characterized by X-ray diffraction, optical and scanning electron microscopy, Energy-dispersive X-ray spectroscopy, differential scanning calorimetry and microhardness. The process parameters will be correlated with the microstructure and phase formation in the samples.