Microstructural Evolution of Laser-Clad IN625 Powder on Rene80 Superalloy
الموضوعات : Journal of Environmental Friendly Materials
M Taheri
1
(Department of Materials Engineering, South Tehran Branch, Islamic Azad University, Tehran, Iran)
A Salemi Golezani
2
(Department of Materials Engineering, Karaj Branch, Islamic Azad University, Karaj, Iran)
الکلمات المفتاحية:
ملخص المقالة :
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 Rene80 superalloy coating with IN625 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 Ni2(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
