Laser stellite coatings on austenitic stainless steels

Abstract High power neodymium-doped yttrium aluminium garnet (Nd-YAG) and CO2 lasers were utilized in remelting stellite coatings applied by an oxyacetylene torch or by tungsten inert gas TIG. A CO2 laser was also utilized to apply the coating directly. The laser-remelted layers have a fine solidification structure, but for both TIG and oxyacetylene applied coatings the technological properties are not significantly improved. Remelting with an Nd-YAG laser refines the structure in very thin layers and, for coatings applied by the oxyacetylene method, extensive crack formation was observed. The best results were obtained by CO2 laser application of the stellite coatings.