Effect of Buffer Layer on <i>In Situ</i> Temperatures in Laser Cladding

Abstract

In laser cladding process, generation of high temperature gradients significantly impacts the output coating parameters such as mechanical and microstructural properties. Buffer layer addition between hard alloys cladding shows reduction in crack formation and also dilution rates. The present study is on Insitu temperature monitoring in laser cladding of Stellite 6 alloy with addition of buffer layer, which were compared with direct deposition of Stellite 6. The results show about 17 - 20 % low substrate temperatures with a buffer layer, indicates more uniform cooling of the hard coatings than direct cladding. The increase in laser power measures 35 - 40 % higher temperatures in both the cases due to large heat addition at the clad region. The study provides an insight into the substrate temperature evolution in cladding with and without a buffer layer.