Effect of Ni on wettability and shear strength of joints of Ag20-CuZnSnP filler metal

By adding different content of Ni into the Ag20-CuZnSnP filler metal, the effect of Ni on wettability and the shear strength of joints are studied and analysed. The results indicate that when the content of Ni is more than 2.0%, the area of wettability on stainless steel is improved obviously; when the content of Ni is 2.0%, the maximum of the shear strength is attained. The analysis of microstructure of filler metals indicate that the size of tin bronze becomes small when the element of Ni is added into the filler metal and the existence of Ni is Ni₃P in which element P is took by Ni from the compound of Cu₃P.