Application of a Lead-free Tin Lining Alloy with Low Corrosion at High Temperature

Abstract

The invention belongs to the field of electronic and electric appliance manufacturing, and relates to tin-based alloy used in high-temperature tin thermal-plating (tin plating) on surfaces of electronic and electric element weld joints. Specifically, the invention provides a Sn-Ni based low-ablation lead-free tin plating alloy under a high temperature. The alloy comprises chemical components of, by weight: 0.1 to 1.5% of Ni, 0.001 to 0.1% of third group components (wherein the third group components indicate one or a composition of components selected from Ag, Cu, Si, P, Ge, Al, Ga, and Ti), and balance of Sn and inevitable impurities. Compared to common tin alloys, the alloy provided by the invention is advantaged in that: a heavy metal lead is not contained in the alloy; and under a relatively high tin plating temperature (300 to 400 DEG C), the ablation speed of the alloy upon a copper substrate is slow. Therefore, the alloy can be widely applied in lead-free surface tin plating technologies of various elements under a high temperature, wherein the elements are manufactured from Cu, Fe, Al, or alloys thereof. The alloy is especially suitable for high-temperature lead-free tin plating technologies on surfaces of small-sized Cu or Cu alloys.

Description

technical field

[0001] The invention belongs to the field of electronics and electrical appliances manufacturing, and relates to a tin-based alloy used for high-temperature hot-dip tinning (tinning) on ​​the surface of solder feet of electronic and electrical components, in particular to a Sn-Ni-based lead-free alloy with low melting corrosion at high temperature Application of tin enamel alloy. Background technique

[0002] In the field of electronics and electrical appliances manufacturing industry, soldering with tin-based solder is one of the most commonly used connection techniques, mainly used in electrical and mechanical connections between metals. In modern industry, copper is currently the best conductive metal, so soldering is mainly used for the connection of copper and copper alloys. Due to being placed under natural conditions, there is a natural oxide film on the surface of copper or copper alloy. During actual welding, molten tin-based solder is not easy to s...

Examples

Embodiment 1

[0023] By weight percentage, prepare Ni0.5%, Ag0.01%, Ga0.01%, Si0.005%, the rest is the Sn-Ni alloy of Sn, selects a kind of common smelting technology to melt industrial pure Sn, then adds Various alloying elements that have been weighed according to the weight percentage are fully dissolved in the liquid Sn, stirred evenly and cast into ingots for use.

[0024] Take the alloy and place it in an open crucible, heat and melt it with a muffle furnace, and raise the temperature to 400°C for 30 minutes to make the temperature of the liquid Sn alloy uniform. Take a section of thin copper wire (Φ0.6mm) with an enameled wire, dip one end into the pre-prepared flux, remove the excess flux, and then immerse it in the prepared liquid Sn-based alloy. After 2 minutes, the surface of the copper wire A layer of Sn has been enameled, soaked in liquid Sn for 5 minutes, and the diameter of the copper wire is taken out to measure 0.5mm. It can be seen that the dissolution rate of the copper w...

Embodiment 2

[0026] By weight percentage, prepare Ni1.0%, Cu0.03%, Ge0.02%, the rest is the Sn-Ni alloy of Sn, adopts the experiment method identical with embodiment 1, enamel tin directly at 400 ℃, has obtained good Effect.

Embodiment 3

[0028] By weight percentage, the Sn-Ni alloy of Ni0.3% and P0.02% is prepared, and the rest is Sn. Using the same experimental method as in Example 1, tinning is directly carried out at 350° C., and good results have been obtained.

technical field

[0001] The invention belongs to the field of electronics and electrical appliances manufacturing, and relates to a tin-based alloy used for high-temperature hot-dip tinning (tinning) on ​​the surface of solder feet of electronic and electrical components, in particular to a Sn-Ni-based lead-free alloy with low melting corrosion at high temperature Application of tin enamel alloy. Background technique

[0002] In the field of electronics and electrical appliances manufacturing industry, soldering with tin-based solder is one of the most commonly used connection techniques, mainly used in electrical and mechanical connections between metals. In modern industry, copper is currently the best conductive metal, so soldering is mainly used for the connection of copper and copper alloys. Due to being placed under natural conditions, there is a natural oxide film on the surface of copper or copper alloy. During actual welding, molten tin-based solder is not easy to s...

Examples

Embodiment 1

[0023] By weight percentage, prepare Ni0.5%, Ag0.01%, Ga0.01%, Si0.005%, the rest is the Sn-Ni alloy of Sn, selects a kind of common smelting technology to melt industrial pure Sn, then adds Various alloying elements that have been weighed according to the weight percentage are fully dissolved in the liquid Sn, stirred evenly and cast into ingots for use.

[0024] Take the alloy and place it in an open crucible, heat and melt it with a muffle furnace, and raise the temperature to 400°C for 30 minutes to make the temperature of the liquid Sn alloy uniform. Take a section of thin copper wire (Φ0.6mm) with an enameled wire, dip one end into the pre-prepared flux, remove the excess flux, and then immerse it in the prepared liquid Sn-based alloy. After 2 minutes, the surface of the copper wire A layer of Sn has been enameled, soaked in liquid Sn for 5 minutes, and the diameter of the copper wire is taken out to measure 0.5mm. It can be seen that the dissolution rate of the copper w...

Embodiment 2

[0026] By weight percentage, prepare Ni1.0%, Cu0.03%, Ge0.02%, the rest is the Sn-Ni alloy of Sn, adopts the experiment method identical with embodiment 1, enamel tin directly at 400 ℃, has obtained good Effect.

Embodiment 3

[0028] By weight percentage, the Sn-Ni alloy of Ni0.3% and P0.02% is prepared, and the rest is Sn. Using the same experimental method as in Example 1, tinning is directly carried out at 350° C., and good results have been obtained.