钛锆钼合金与钨铼合金的SPS扩散焊接

采用放电等离子烧结(SPS)技术对TZM合金与WRe合金进行固相扩散焊接，研究了TZM/WRe接头的微观组织、力学性能和热疲劳性能. 结果表明，SPS扩散焊接技术在1 500 ℃保温30 min成功实现了TZM合金与WRe合金的高效连接，焊缝平整，无微裂纹、微孔洞和未焊合等焊接缺陷；TZM合金与WRe合金扩散焊接过程中均发生了再结晶，与W和Re相比，Mo具有较低的自扩散激活能，导致Mo的扩散深度大于W和Re在TZM合金中的扩散深度；TZM/WRe接头经历100次热震试验后，焊缝完好无裂纹，且部分再结晶Mo晶粒跨界生长；TZM/WRe接头的抗弯强度和抗剪强度分别为910 MPa±65 MPa，497 MPa±50 MPa，断裂失效发生在TZM合金一侧，断裂模式主要为穿晶解理断裂.

Diffusion bonding between TZM alloy and WRe alloy by spark plasma sintering

Solid-state diffusion bonding of TZM alloy to WRe alloy was performed using spark plasma sintering (SPS). The microstructure, mechanical properties and thermal fatigue of the TZM/WRe joint were investigated in detail. The results showed that successful solid-state diffusion bonding was achieved between TZM alloy and WRe alloy using SPS at temperature of 1 500 °C for 30 min. The TZM/WRe interface is free from discontinuities or microcracks. Recrystallization occurs in both the TZM alloy and WRe alloy during diffusion bonding. comparison with W and Re, the diffuse depth of Mo is greater than that of W and Re in the TZM alloy, due to its lower self-diffusion activation energy. The TZM/WRe joint shows excellent resistant ability to thermal shock and part of Mo grains grow through the TZM/WRe interface after enduring 100-cycles thermal shock. The bending strength and shearing strength of the TZM/WRe joint are 910 MPa±65 MPa, 497 MPa±50 MPa, respectively. Fracture occurs in the TZM alloy, and the fracture mode is dominated by transgranular cleavage fracture.