Microstructure and properties of CMSX-4 single crystal superalloy TLP bonded joints

Si-contained BNi-5 amorphous foil was used as an interlayer alloy in TLP bonding of CMSX-4 nickel-based single crystal superalloy rods in a spark plasma sintering furnace. The TLP joints heated at different temperatures and varied time were analyzed by SEM and EDS to study the microstructures and the phase composition at the interface in TLP joints. The influences of different welding process on the performance of TLP joints were verified by normal temperature and high temperature tensile tests. The result shows that an optimized TLP joint can be obtained at process parameters of 1 200 ℃,5 k N and 20 min. The microstructure in joint is uniform. The tensile strength at room temperature reaches 95% of that of BM,and the tensile strength at 760 ℃ reaches up to 99% of that of BM.