Influence of rare-earth La2O3 on the properties of laser cladding on 316L stainless steel coatings

The ball valve is an important part of the blast furnace in Shanghai Baosteel. The damage to ball valves is mainly in the spheroids. Laser cladding is a very useful method of repairing the spheroid surface. In this paper, the influences of rare-earth La2O3 on the properties of laser cladding on 316L stainless steel coatings have been researched experimentally. From the researches, some results have been obtained. A certain content of rare-earth La2O3 can prominently fine and purify the organization of the coatings, suppress the growth of the columnar crystal and dendrite and reduce the interval of grains. Rare-earth La2O3 can raise the corrosion-resistant ability of the coatings. The rare-earth La2O3 has uniformed the performance of the coatings while improving the hardness of the coatings and the hardness distribution of the coatings tends to be even. The correct rare-earth La2O3 content can reduce and eliminate the micro crackles induced by laser cladding.