The effect of a coating heat-treatment on Cr–Si and heat-treatment on the mechanical properties of Cr17Ni2 stainless steel

The in-situ co-deposition of Cr–Si into Cr17Ni2 stainless steel (similar to AISI 431) was achieved using a pack cementation process. Through the optimum parameters, a coating containing approximately 27 wt.% Cr and 2 wt.% Si was obtained, with a layer thickness of approximately 120 μm. Studies showed that the thermal treatment of the coating resulted in a reduction of tensile strength, but the improvement of impact toughness, although the coating had little effect on the mechanical properties of the bulk. Tempering at 300 or 450°C improved the tensile strength and the impact toughness of the steel at 9 and −55°C, while tempering at 550°C reduced these mechanical properties.