Interfacial microstructure and mechanical properties of TZM alloy and ZrC particle reinforced tungsten composite joint brazed using Ti-61Ni filler

TZM alloy and ZrC particle reinforced W composite (ZrCp-W) were vacuum brazed using Ti-61Ni eutectic brazing alloy. The typical interfacial microstructure of the brazed joint consisted of three zones: a Mo solid solution layer, a brazing seam consisting of TiNi phase, TiNi3 phase and (Ti, Zr)Ni2 phase, and a diffusion layer composed of W particles, (Ti, Zr)C particles and (Ti, Zr)Ni2 phase. The results revealed that brazing temperature affected the interfacial morphologies of the joint, the phase constituents of the brazing seam, the element contents of these phases and the mechanical properties of the brazed joint. The optimal shear strengths at room temperature and at 800 °C reached 124.8 MPa and 82.3 MP respectively when brazed at 1240 °C for 10 min. Meanwhile, the fracture paths located at the TZM substrate and the fracture surface exhibited inter-granular fracture characteristics.