Laser cladding of a wear-resistant TiN_p/Ni-base alloy composite coating

A 2kW CO2 laser was employed to clad a TiNp/Ni-alloy composite coating on steel 1045. The analysis shows that (1) the clad layer exhibits TiN particles, γ-Ni primary dendrites and the eutectics of γ-Ni+(Fe, Cr)23 (CB)6 in the interdendritic regions; (2) the high density dislocations in γ-Ni primary dendrites and a large amounts of stacking-faults within (Fe, Cr)23 (CB) phase are observed; (3) partial dissolution appearing on the edges of original TiN particulates and their regrowth in the form of independent fine dendrites during resolidification are found in the cladding region; (4) the addition of TiN particulates into the Ni-alloy coating greatly improves the wear resistance of the composite coating.