Method for laser hardening gear part

The invention discloses a method for laser hardening gear part, which comprises the following steps: 1) machining a gear part according to the prior art, wherein the thickness of the gear is required to be 1.5 mm less than the design value; 2) laser scanning the gear part by a laser hardening equipment with a laser output power of 5 kw, a scanning speed of 480 mm/min, and a powder feed rate of 18g/min, performing the powder feeding and the laser cladding simultaneously in one work step, and cladding the gear surface with metal powder containing wear resistant materials to form a laser hardening layer with a cladding thickness of 3 mm and with polishing allowance reserved, wherein the laser beam is a broadband rectangular spot of 15X2.5; the metal powder material comprises, by weight: 48.4% of Fe, 0.077% of C, 0.85% of Si, 0.368% of Mn, 17.02% of Cr, 24.4% of Ni, and 2.68% of Mo; 3) processing the laser-clad mating surface to achieve a design size. The laser-clad gear of the present invention has an average mi