Microstructural Evolution of Laser-Clad IN۶۲۵ Powder on Rene۸۰ Superalloy

Nickel-based superalloys are one of the main components of fixed and moving blades of land and air gas turbines. Susceptibility of substrate and coating during Rene۸۰ superalloy coating with IN۶۲۵ was investigated by laser cladding method. For this purpose, the substrate was selected under two conditions of casting and solution heat treatment. Microstructural studies showed that the coating, despite maintaining its hardness due to NbC carbide and Ni۲(Cr,Mo) phases, did not form cracks and pores. However, in the coating-substrate interface and heat affected zone of the casting sample, cracking occurred due to the high absorption of process stresses by MC carbide (TiC) and γ´ phase as well as partial melting of these two phases. However, in the case of heat treatment, due to the dissolution of these phases and the low hardness of the substrate, the conditions of non-stress absorption and stress release further reduced the sensitivity to cracking

کلیدواژه ها:

Laser Cladding ، Rene۸۰ ، IN۶۲۵ ، HAZ Crack