Leadless soft brazing material

Abstract

The invention discloses a lead-free soft soldering solder having three basic formations, namely that stannum is used as a base, and according to weight percentage, the solder also comprises 0.1 to 3.0 percent of copper and 0.01 to 0.5 percent of aurum, or also comprises 0.1 to 3 percent of copper and 0.01 to 0.5 percent of platinum, or comprises 0.1 to 3 percent of copper and aurum and platinum which totally occupy 0.01 to 0.5 percent. Argentum and (or) indium, of which the content is not higher than 4 percent according to weight percentage are added to the solder. The lead-free soft soldering solder has favorable antioxygenic property, and effectively avoid the phenomenon of hole blockage during secondary welding; and the production method is simple and is easy to be realized for industrial purposes.

Description

technical field [0001] The invention relates to a lead-free solder. Background technique [0002] At present, the commonly used solder in the electronics industry is tin-lead alloy. Because tin-lead alloy has good wettability and electrical conductivity, good soldering performance and low cost, it is widely used. However, lead and its compounds are very polluting to the environment and will endanger the health of human beings and organisms. From the beginning of this century, countries around the world have increasingly stringent requirements for environmental protection. In the field of electronic soldering, many developed countries, especially the United States and Japan, have already started research on lead-free solder. Many international companies also use lead-free solder in the production of common consumer products, such as motherboards of MinDisc personal computers, notebook computers, mobile phones, TVs, and VCRs. It can be seen that the market potential of lead...

AI Technical Summary

Problems solved by technology

However, lead-free solder still needs to be improved in terms of soldering performance. Many lead-free solders used by famous international companies with advanced technology still have shortcomings to varying degrees, such as the SnAgBiIn and SnCu solder alloys used by Mitsubishi, and the SnAgCu solder alloys used by Toshiba. , SnAgCu and SnAgBi solder alloys used by Hitachi, SnZn, SnCu, SnZnBi and SnAgCu used by NEC, etc.

In these solder alloys, after the hot air leveling and tinning of the circuit board, hole plugging and oxidation are prone to occur during secondary soldering.

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