Heat-resistant and moisture-resistant low-melting-point lead-free solder alloy
A lead-free solder alloy, lead-free solder technology, applied in welding/cutting media/materials, welding media, welding equipment, etc., can solve the problems of surface oxidation corrosion, poor oxidation resistance, resistance change, etc. Oxidation resistance, good wettability, and crack reduction effect
Active Publication Date: 2013-04-17
马莒生
View PDF5 Cites 15 Cited by
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
[0005] However, the alloy has poor oxidation resistance under high temperature and high humidity conditions. When it is at 85°C85%RH (relative humidity) for 500 hours, there is no problem for 1000 hours. When it is more than 1000 hours, the surface of the solder joint is severely oxidized and corroded, reaching 2000 The surface crack can reach 220 μm after 1 hour, although it is better than the 2000-hour crack of Sn8Zn3Bi 394 μm, but the oxidation resistance of the alloy needs to be improved, and because zinc is easy to oxidize, hydrogen ions H will be generated under the action of water vapor + , H + Into the alloy, causing resistance changes and hydrogen-induced cracking problems
Method used
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View moreExamples
Experimental program
Comparison scheme
Effect test
Embodiment 1
[0030] The weight percent of each chemical composition in the lead-free solder alloy is: Zn: 10, Bi: 2.5, In: 1.5, P: 0.5, Zr: 0.001, and the balance is Sn.
[0031] The melting point of the solder obtained in this embodiment is 196°C, and the wetting angle θ is 32°. The surface crack depth of the solder joint is 174 microns at 85°C85%RH (relative humidity) for 2000 hours.
Embodiment 2
[0033] The weight percent of each chemical composition in the lead-free solder is: Zn: 12, Bi: 0.5, In: 5.0, P: 0.21 Zr: 0.1, B: 0.02, and the balance is Sn.
[0034] The wetting angle θ of the obtained solder was 37.5°. The crack depth on the surface of the solder joint is 185 microns after 2000 hours at 85°C85%RH (relative humidity).
Embodiment 3
[0036]The weight percent of each chemical composition in the lead-free solder is: Zn:8, Bi:4, In:0.5, P:0.1, Zr:0.25, Mg:0.02, and the balance is Sn.
[0037] The wetting angle θ of the obtained solder was 37°. The surface crack depth of the solder joint is 190 microns at 85°C85%RH (relative humidity) for 2000 hours.
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More PUM
| Property | Measurement | Unit |
|---|---|---|
| melting point | aaaaa | aaaaa |
| melting point | aaaaa | aaaaa |
| melting point | aaaaa | aaaaa |
Login to View More
Abstract
The invention relates to a heat-resistant and moisture-resistant low-melting-point lead-free solder alloy, and belongs to the technical field of an electronic material and electronic preparation. The solder alloy comprises the following chemical components in percentage by weight: 4-12% of Zn, 0.5-4% of Bi, 0.5-5.0 In, 0.005-0.5 of P, and 0.001-0.5 of Zr; meanwhile, one or more than one microelement, such as Y, Ge, Mg, B, Al, Ni or Ag, is added; and the balance is Sn. A melting point of the solder alloy is reduced due to lead-free solder, so that the defect of separation of a welding spot can be avoided; an alloy structure is micronized and is uniform, and cracks can be prevented from expanding, so that alloy strength is improved; and the heat-resistant and moisture-resistant low-melting-point lead-free solder alloy has the characteristics of high-temperature resistance, high-moisture resistance and small infiltration angle, can be machined to be a finished material, such as a rod, a wire, powder and a spherical material, and can be prepared into soldering paste. The heat-resistant and moisture-resistant low-melting-point lead-free solder alloy can be used for various soldering manners and can meet various requirements.
Description
technical field [0001] The invention belongs to the technical field of electronic materials and electronic manufacturing, and in particular relates to a low melting point lead-free solder alloy resistant to high temperature and high humidity. Background technique [0002] The Sn-Pb eutectic alloy with a melting point of 183°C has been the main brazing material in the electronics industry for a long time, and occupies a dominant position in the assembly of electronic components. Although the alloy has excellent wettability, weldability, electrical conductivity, mechanical properties, and low cost, due to the toxicity of Pb and Pb compounds, improper use will pollute the environment and damage the health of workers. The laws and regulations are becoming more and more perfect and strict, and the laws prohibiting the use of lead-containing solder in the electronics industry are being implemented all over the world. In June 2000, the fourth edition of the US IPC Lead Free Roadmap...
Claims
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More Application Information
Patent Timeline
Login to View More Patent Type & Authority Applications(China)
IPC IPC(8): B23K35/26
CPCB23K35/26C22C13/00B23K35/0222B23K35/0227B23K35/0244B23K35/025B23K35/24B23K35/262C22C13/02
Inventor 马莒生
Owner 马莒生