Influences of In on the Microstructure and Mechanical Properties of Low Silver Ag-Cu-Zn Filler Metal

Abstract:

To develop novel low silver based filler metals used for brazing brass and 304 stainless steel. The microstructure morphology and the wettability of low silver based filler metals were observed by using scanning electron microscopy (SEM) and electrical resistance furnace. The results indicate that, the wettability of the low silver based filler metals imporved with increasing indium content. Brass and stainless steel were brazed with flame method, the mechanical properties of lap joint were tested and analyzed at the same time. It is found that the tensile strength of joints increased with the addition of indium due to the solution strength effect. The shear strength of joint brazed with the 17AgCuZn-1In filler metal reached 312.6MPa closes to joint brazed with the B25AgCuZnSn filler metal. The joints part formed via brazing the 304 stainless steel and brass with 17AgCuZn-1In by flame brazing, had no defects at all, which, meanwhile, proved its good performance.