A microstructural modification strategy to improve thermal conductivity of tool steels produced by laser powder bed fusion

Materials Characterization, vol. 211, pp. 113917

Abstract

Laser additive manufacturing is a promising technology for producing tools with complex geometry. The tools for hot working applications typically require high thermal conductivity to reduce thermal stresses. However, the relationship between thermal conductivity and the unique microstructure created by Laser Powder Bed Fusion (LPBF) is not yet fully understood. In this study, we investigated the thermal conductivity of AISI M50 in the as-built and different heat-treated conditions. As-built samples exhibited anisotropy and low thermal conductivity. The low thermal conductivity can be improved after heat treatments by modifying the microstructure. Moreover, the influence of each microstructural characteristic was interpreted. Thereby, a correlation between thermal conductivity and microstructure can be addressed. With this knowledge, we proposed a suitable heat treatment concept for improving the thermal conductivity of additively manufactured tool steels.

Authors 4

1. Siyuan Qin corresponding Aachen Institute for Materials Applications in Mechanical Engineering

   RWTH Aachen University

   Affiliation as printed

   Institute for Materials Applications in Mechanical Engineering (IWM) at RWTH Aachen University, Augustinerbach 4, 52062 Aachen, Germany

2. Simone Herzog Aachen Institute for Applied Powder Metallurgy and Ceramics Institute for Materials Applications in Mechanical Engineering

   RWTH Aachen University

   Affiliation as printed

   Institute for Applied Powder Metallurgy and Ceramics (IAPK) at RWTH Aachen University, Augustinerbach 4, 52062 Aachen, Germany

   Institute for Materials Applications in Mechanical Engineering (IWM) at RWTH Aachen University, Augustinerbach 4, 52062 Aachen, Germany

3. Anke Kaletsch Aachen Institute for Applied Powder Metallurgy and Ceramics Institute for Materials Applications in Mechanical Engineering

   RWTH Aachen University

   Affiliation as printed

   Institute for Applied Powder Metallurgy and Ceramics (IAPK) at RWTH Aachen University, Augustinerbach 4, 52062 Aachen, Germany

   Institute for Materials Applications in Mechanical Engineering (IWM) at RWTH Aachen University, Augustinerbach 4, 52062 Aachen, Germany

4. Christoph Broeckmann Aachen Institute for Applied Powder Metallurgy and Ceramics Institute for Materials Applications in Mechanical Engineering

   RWTH Aachen University

   Affiliation as printed

   Institute for Applied Powder Metallurgy and Ceramics (IAPK) at RWTH Aachen University, Augustinerbach 4, 52062 Aachen, Germany

   Institute for Materials Applications in Mechanical Engineering (IWM) at RWTH Aachen University, Augustinerbach 4, 52062 Aachen, Germany