To cope with requirement of lead-free electronic assembly, we developed lead-free solder bar with composition of alloys such as Sn-Cu、Su-Ag、Sn-Sb、Sn-Bi、Sn-In、Sn-Ag-Cu etc. The products’content of lead less than 1000ppm. With elaborately designed flux the alloys solder wire is able to work well at higher jointing temperature, and eventually achieve lead-free assembly.