Abstract:
The Si
3N
4 ceramics was brazed to TiAl alloys with Ti/Ag-Cu/Cu as the interlays, and a good joint was obtained. The interfacial microstructure of the joint and the elements were analyzed by scanning electron microscope (SEM) and energy dispersive spectrometer distribution (EDS). The results show that the typical interfacial microstructure of Si
3N
4/Ti/Ag-Cu/Cu/TiAl may be Si
3N
4/TiN/Ti-Si/Cu-Ti+Ag(s,s)+Cu(s,s)/AlCuTi/TiAl. The influences of brazing temperature, holding time and the pressure of the joint on the four-point bending strength of the joint were researched by using controlling variables method. The four-point bending strength of the joint reaches the maximum of 170 MPa when the brazing temperature, holding time and the pressure of the joint are 1 133 K, 30 min and 0.040 MPa, respectively.