Facile preparation and tribological property of alloyed Fe3Si coatings on stainless steels surface by molten-salt infiltration method

Abstract Alloyed Fe3Si infiltration coatings on the surface of 2Cr13 and 0Cr18Ni9 stainless steels were easily prepared via non-electrolysis infiltration in a molten salt. The infiltrated coatings on a 20 carbon-steel surface were used for comparative study. The microstructure of each infiltration coating was examined via XRD and SEM. The hardness and toughness of Fe3Si coatings were investigated by using a microscopic hardness tester, nano-indentation and static-indentation tests. Furthermore, the wear resistance of the coatings was evaluated using a ball-on-disk wear tester. The results indicated that alloying elements in the stainless-steel substrates participate in the mutual thermal diffusion of Fe-Si and alloyed Fe3Si coatings containing elemental Cr and Cr, Ni can be easily obtained. Cr and Ni alloying elements can increase the growth rate of the infiltration coatings, help to reduce the defect density, and improve the compactness of these coatings. In addition, the surface wear resistance capacity of alloyed Fe3Si coatings was 2.3 times and 3.7 times that of the corresponding 2Cr13 and 0Cr18Ni9 stainless-steel substrates, respectively. The reason lie in that Cr- or (Ni, Cr)- alloying has endowed Fe3Si coating higher hardness and surface toughness simultaneously.