Effect of laser specific energy on mechanical properties of Fe60 coatings by laser cladding

To reveal the effect of laser specific energy on the mechanical properties of Fe60 coatings, and determine the laser specific energy as well as the corresponding process parameters for the optimal mechanical properties of the coatings, Fe60 coatings were prepared on the surface of 304 stainless steels by laser cladding. The microhardness, tensile properties, and impact properties of the coatings were investigated at different laser specific energies by changing the laser power and scanning speed. The results show that the Fe60 coatings are mainly composed of cryptocrystalline martensite, carbides, a small amount of ferrite and residual austenite. Compared with the substrate, the microhardness of Fe60 coatings is significantly increased, the tensile properties of Fe60 coatings are reduced, the brittle cleavage fracture characteristics are presented, and the impact toughness of Fe60 coatings is slightly reduced. With the increase of laser specific energies, the microhardness, tensile properties, and impact properties of the coatings show a trend of increasing and then decreasing. When the laser power is 2300 W, the scanning speed is 11 mm/s, and the laser specific energy is 105 J/mm2, the coatings with the optimal mechanical properties can be obtained. The results can provide a reference for preparing Fe60 coating of excellent performance by adjusting the laser specific energy through synthetically coordinating the laser cladding process parameters.