Grant: Collaborative Research and Development Grants

Brazing is a relatively low cost joining process used in many applications by the aerospace industry. However,some of the critical parameters to ensure braze joint reliability are still to be determined. Pratt & WhitneyCanada (PWC) and Turbomeca Canada (TMC) use many brazing pastes for stainless steels and Nickel basedsuperalloys for non-structural applications and reapers. Sometime, the braze reproducibility and success inpost-brazing testing is not consistent. More understanding of the wetting behaviour combined with thecharacterisation of the industrial brazing process is required. Achieving reproducibility and reliability, togetherwith understanding of all aspects related to braze metal wetting behaviour as well as microstructure-mechanicalproperty relationship is the first goal for this research. This includes surface tension characterization, liquidbraze wetting behaviour, fluidity of filler metal, brazing gap and diffusion into the parent metal in order to ensure successful brazing for gas turbine components. Moreover, brasing of titanium alloys is a new andrelevant domain to investigate in the framework of turbine applications. The other objective will be todetermine the potential of brazing alloys to carry structural loading during operation of gas turbine engines. Infact, such a versatile joining process (as it is possible to assemble dissimilar alloys easily) could replacewelding processes that result in major component distortion and affects the dimensional tolerances of machinedparts.