Soldering of Copper with High-temperature Zn-based Solders.

The work deals with the study of interaction Cu substrate (purity 5N) and Zn4Al and Zn6Al6Ag (purity 4N) 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 5 s. Soldered joints were assessed by optical light microscopy, EDX microanalysis and DSC analysis. It was found out that the melting temperatures of solders were 404.9 °C and 396.9 °C. Intermetallic layers (IM) CuZn 4 and Cu 5 Zn 8 were formed at the Cu/Zn4Al boundary. At the boundary Cu/Zn6Al6Ag there were formed AgZn 3 and Cu 5 Zn 8 IM layers. Shear strength of joint Cu/Zn4Al was 34.5 MPa and shear strength of Cu/Zn6Al6Ag was 39 MPa. [ABSTRACT FROM AUTHOR]