Influence of preheating temperatures on material properties of PBF-LB manufactured hot-work tool steel X37CrMoV5-1

Abstract

Processing of high-carbon tool steels with laser-based powder bed fusion (PBF-LB) can lead to thermal and stress-induced cracks. Defect-free processing is often realized by using base plate preheating. The temperature level during the building process is influenced by laser energy input and the surrounding conditions. Due to the layer-by-layer structure, heat treatment effects occur along the building height of the specimen, affecting the material properties. In-situ heat treatment can be used to reduce post-processing. A tempering process is required for preheating temperatures up to 500°C, which can be omitted at higher preheating temperatures.The hot-work tool steel X37CrMoV5-1 is processed at preheating temperatures between 200°C and 800°C. Base plate and top-level sample surface temperature are monitored during the building and cooling. The influence of heat treatment effects is discussed based on the microstructure, retained austenite and hardness along the building height.