CMSX-4单晶高温合金TLP接头组织与性能

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

采用含Si的BNi-5非晶箔片作为中间层合金对CMSX-4镍基单晶合金棒在放电等离子体烧结炉中进行TLP连接,采用SEM观测了TLP接头在不组织形貌特征,借助于EDS分析了TLP接头界面处的物相组成及其对接头力学性能的影响。采用常温和高温拉伸试验验证了不同焊接工艺条件对TLP接头性能的影响。结果表明,在1 200℃/5 k N/20 min工艺参数下可得到满意的TLP接头,此时组织分布较为均匀,常温抗拉强度达到了母材的95%,760℃高温抗拉强度达到母材的99%。

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.