12th Tooling Conference & Exhibition - Tooling 2022

Laser Powder Bed Fusion (LPBF) is an additive manufacturing process that enables the production of complex shaped components. Conventional high-carbon tool steels tend to cracking and warping during LPBF due to internal stresses caused by the rapid solidification. Expensive atomization and long lead times for powder generate high costs for material development in this processing route.
The Laser Powder Bed Alloying (LPBA) of powder blends from conventionally available powders enables a more flexible approach of alloy design. For industrial use, the mechanical properties of LPBF parts must be comparable to those of conventionally manufactured parts. High chromium cold work tool steels, as used in cutting applications, need to possess sufficient abrasive wear - and corrosion resistance. In this study, AISI H13 has been modified by Cr3C2 and elemental chromium to suit these requirements. A novel alloy was modelled thermodynamically and processed by LPBA. In-depth microstructural investigations by backscatter electron imaging and electron backscatter diffraction in combination with ASTM G65 abrasive wear tests and potentiodynamic polarization curves allow microstructure property correlations for different heat-treated conditions. Crack-free processing, hardenability, formation of chromium-rich carbides and residual Cr-rich inclusions were observed and their influence on the wear- and corrosion resistance is discussed.