Laser Metal Deposition of Carbide-reinforced low-alloyed steel Bainidur AM

Abstract

Case-hardening steels are typically exposed to a post-process carburization or nitriding chemical heat treatment. Laser-based directed energy deposition (DED-LB\\M) provides the possibility of substituting this case-hardening step through applying a wear resistant coating. The powder-based process allows for the addition of hard phase particles to the feedstock powder for generating advantageous coatings compared to e.g., solely carburized surfaces. Within this work, the addition of WC hard phase carbides to the low-alloyed steel Bainidur AM is investigated. It is found that the metal matrix is strengthened when adding the WC carbides. Depending on the carbide content and processing strategy, different material hardness through dispersion and partial solving of the carbides are present. Furthermore, a correlation between the applied processing strategy and the material hardness is identified as higher laser power e.g., favor a stronger mixing with the softer substrate.