Diffusion brazing of GH536 polycrystalline superalloy with IC10 single crystal superalloy using BNi-2 interlayer

Joining single crystal superalloy with polycrystalline superalloy has important applications in the aerospace industry. Here, the IC10 single crystal superalloy to GH536 polycrystalline superalloy was diffusion brazed using a BNi-2 filler alloy. The effects of bonding temperature and time on the microstructure evolution and mechanical properties of the GH536/ IC10 joints were investigated in detail. The results elucidated that the joint brazed at a lower temperature and time (i.e., 1050 & DEG;C/30min) was composed of diffusion affected zone (DAZ), athermal solidification zone (ASZ), and isothermal solidification zone (ISZ). The secondary precipitates formed in DAZ were Cr-rich borides, Cr-Mo borides, and Cr-Mo-W borides. The ASZ was made up of Cr-rich borides, Ni-rich borides, Ni-Cr borides, and Nibased solid solutions. These borides with high hardness were the potential source of cracks and caused the joints to fracture under a lower load. Raising bonding temperature and time gradually eliminated Ni-rich borides in ASZ and Cr-rich borides in DAZ, and improved the shear strength. & COPY; 2023 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Automated summary

The effects of bonding temperature and time on the microstructure and mechanical properties of the joint between IC10 single crystal superalloy and GH536 polycrystalline superalloy were investigated. Lower temperature and time resulted in the formation of hard borides, leading to lower shear strength.