Influence of baseplate heating and shielding gas on distortion, mechanical and case hardening properties of 16MnCr5 fabricated by laser powder bed fusion

Additive manufacturing, especially laser powder bed fusion (LPBF), allows the build-up of complex parts and is, therefore, used in various industries. In order to exploit the potential in the automotive industry, the range of materials must be extended to include case-hardening steels, which are used in drivetrain parts. This paper examines the distortion of samples manufactured of the case-hardening steel 16MnCr5 (1.7131) via LPBF at varied baseplate temperatures and shielding gases, and also closely evaluates the resulting microstructure and hardness. Depending on the baseplate temperature, tempering or stress-relief annealing effects can be observed. For further insights into the process chain, dependencies between case hardening properties and manufacturing parameters are described.