Lead-free soldering tin wire

Abstract

The invention discloses a lead-free soldering tin wire. The lead-free soldering tin wire is characterized by comprising, by mass, 1.5-8% of Cu, 0.01-2% of Co, 0.01-1% of Ni, and the balance Sn. The liquidus temperature of the lead-free soldering tin wire is 420 DEG C or below 420 DEG C. The lead-free soldering tin wire can further comprise one or more oxidation inhibition elements and / or one or more wetting improvement elements, and a composition of P, Ge and Ga or a composition with 0.05-2% of Ag by mass can be selected and used as the wettability improvement elements. The lead-free soldering tin wire coats the end portion of a copper wire coil. The lead-free soldering tin wire has the advantages that the lead-free soldering tin wire can not be subjected to copper leaching easily when being used in a molten state, the phenomenon of lead poisoning can be reduced, and the lead-free soldering tin wire is practical and convenient to use.

Description

Technical field

[0001] The invention involves a welding wire, especially a lead -free welded wire. Background technique

[0002] In electronic devices, various coils can be used in computers.Welding at the end of the coil is preferred to ensure a satisfactory welding joint after using the welding wire pre -coating end.This pre -coating can be immersed in the welded wire of the coil.Some copper wires used in electronic devices to make coils are thin to 100 microns or smaller in diameter.When the end of such a thin copper wire is immersed in the melting welding wire, the so -called copper may occur.Copper immersion is such a phenomenon, that is, the fine copper wires immersed in the melting welding wire are dissolved in the melting welded wire, which makes the wires thinner or completely disappear.Copper immersion may also occur during welding process at the end of the coil, especially in the welding process.In the past, countermeasures have been adopted to prevent copper in the fi...