Metal Additive Manufacturing Conference 2019

In this study, tempering behaviour of AISI H13 fabricated by Selective Laser Melting (SLM) in as-built and “austenitized and quenched” conditions are evaluated. Compared to the austenitized and quenched counterpart, secondary hardening peak is more pronounced and is shifted to a higher temperature in directly tempered H13. It is shown that the decomposition of retained austenite (RA), up to 19vol% in as-built H13, during tempering is responsible for the different tempering behaviour. In spite of significantly higher hardness of the directly tempered parts, comparable fracture toughness is achieved for both samples. In view of the improved hardness, mechanical properties and thermal stability, it is suggested that direct tempering can be sucsessfuly applied to the additively manufactured tool steel parts.