Development of high-temperature solders: Review

The development of lead-free solder alloys for high-temperature applications is required to meet increasing demands for reliable replacements for lead-containing alloys. This paper provides a review of recent research on suitable replacement alloys, as well as traditional Pb–Sn alloys, collating relevant properties and identifying areas where further development is required. The main candidate alloys covered are derived from the Au–Sn, Au–Ge, Zn–Al, Zn–Sn, Bi–Ag and Sn–Sb alloy systems. Each of these systems is discussed with respect to the advantages and disadvantages associated with their use in soldering applications. It is concluded that further development of alloys suitable for high-temperature lead-free soldering applications is required.