Influence of the filler metals' forms on semi-solid pressure reaction brazing joints

70% SiC_p/Al composites were semi-solid pressure reaction brazed with the Al-Si-Mg-Cu-Ti filler metal in different forms, the connotation of the welding method was expounded, and the microstructures and properties of the joints were analyzed. The results indicated that the joints mainly contain Al matrix, dark gray ringed and massive Ti₇Al₅Si₁₂ compound, and massive Ti phase when they were filled with pulverous filler metal; the joints mainly contained Al matrix and short clubbed Ti₇Al₅Si₁₂ compound when they were filled with schistose filler metal. The bonding of interface was the main factor affecting the performance of the joint. The filler metal and the base material were fully combined during brazing when they were filled with powder filler metal, which provided many atomic diffusion channel at the interface of the joint, so that they were well combined without clear dividing line, the shear strength of the joint reached 92.1 MPa, and the fracture was ductile and brittle mixed fracture; There was clear dividing line at the interface when the filler metal was schistose, so that the shear strength of the joint was low, 43.9 MPa, and the fracture was brittle fracture.