Research of Interaction Between Zn Based Solders and Cu, Al Substrates

The paper deals with the study of interaction between Cu, Al substrates (purity 5N) and ZnAl₄, ZnAg₆Al₆ zinc solders for higher application temperatures. Soldering was performed with power ultrasound in the air without flux application at temperature 420 °C. Acting time of ultrasonic vibration was 3 s and ultrasound frequency was 40 kHz. Soldered joints were assessed by optical light microscopy and EDX microanalysis. Intermetallic layers (IM) CuZn₄ and Cu5Zn₈ were formed at the Cu/ZnAl₄ boundary. The βZn-αAl mechanical mixture was formed at the Al/ZnAl₄ boundary. AgZn₃ and Cu5Zn₈ IM layers were formed at the Cu/ZnAg₆Al₆ boundary, and mechanical mixture of βZn-αAl and AgZn₃ intermetallic mixture were formed at the boundary Al/ZnAg₆Al₆.