Silver-free lead-free solder

Abstract

The invention discloses silver-free lead-free solder which comprises Cu, Bi, Ce, Ni and Sn. The silver-free lead-free solder is safe, environmentally friendly, low in melting point, low in cost, high in reliability, long in preservation and recyclable.

Description

technical field [0001] The invention relates to a solder, in particular to a silver-free and lead-free solder. Background technique [0002] For a long time, near-eutectic Sn-Pb solder has been widely used in the connection and assembly of electronic circuit boards because of its good soldering performance, good wetting performance on Cu base, low melting point and cheap price. Rich experience and technology have been accumulated in decades of use. However, due to the high toxicity of Pb and its compounds, it will bring greater harm to human health and the safety of the living environment. The harm of lead to children is particularly serious. It will directly affect IQ and normal development. With the rapid development of the electronics industry, a large number of Electronic products are eliminated, and the poisonous Pb in the buried electronic products is dissolved by chemical reaction, enters the soil and pollutes the groundwater source. After humans drink water containi...

AI Technical Summary

Problems solved by technology

However, due to the high toxicity of Pb and its compounds, it will bring greater harm to human health and the safety of the living environment. The harm of lead to children is particularly serious. It will directly affect IQ and normal development. With the rapid development of the electronics industry, a large number of Electronic products are eliminated, and the toxic Pb in discarded electronic products after burial is dissolved by chemical reaction, enters the soil and pollutes groundwater sources, and after humans drink water containing Pb, Pb is deposited in the body, resulting in Pb poisoning

At the same time, in electronic assembly, long-term exposure of workers to Pb-containing environments or contact and breathing of Pb during manual soldering, as well as improper handling, transportation or regeneration of Pb containing waste residues, may cause harm to the body.

[0003] At present, people have conducted a lot of research on lead-free solder, but the lead-free solder currently used has problems such as high melting point, poor wettability, and high cost. Under the conditions of suitable melting temperature, wettability, mechanical properties, reliability and cost, An ideal substitute for lead-tin solder has not yet been found