HIGH-STRENGTH LOW-TEMPERATURE LEAD-FREE SOLDER AND PREPARATION METHOD THEREFOR

摘要

Disclosed is a high-strength low-temperature lead-free solder comprising the following components in parts by weight: 0.1-0.4 parts of nano titanium nitride, 0.05-0.1 parts of zirconium borate, 50-80 parts of an Sn-In alloy micropowder and 1-3 parts of a flux, wherein the Sn-In alloy micropowder comprises the following components in mass percentage: 30.5-59.5% of In, 0.1-0.5% of Cu, 0.03-0.05% of Ag, 0.001-0.002% of Cr, 0-0.001% of Co, 0.001-0.002% of La, 0.0005-0.001% of Y, 0.001-0.003% of Zn, 0.001-0.003% of Ti, and the balance being Sn and inevitable impurities. The lead-free solder contains no lead element, meets environmentally friendly requirements, and has good mechanical properties and an excellent solderability. The present invention also relates to a preparation method for the high-strength low-temperature lead-free solder.