CN107999996B - tin-base lead-free solder alloy for soft soldering of aluminum and aluminum alloy - Google Patents
tin-base lead-free solder alloy for soft soldering of aluminum and aluminum alloy Download PDFInfo
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- CN107999996B CN107999996B CN201711323580.8A CN201711323580A CN107999996B CN 107999996 B CN107999996 B CN 107999996B CN 201711323580 A CN201711323580 A CN 201711323580A CN 107999996 B CN107999996 B CN 107999996B
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- aluminum
- alloy
- tin
- brazing
- free solder
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K35/00—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting
- B23K35/22—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting characterised by the composition or nature of the material
- B23K35/24—Selection of soldering or welding materials proper
- B23K35/26—Selection of soldering or welding materials proper with the principal constituent melting at less than 400 degrees C
- B23K35/262—Sn as the principal constituent
Abstract
The invention belongs to the field of brazing materials, and discloses a tin-based lead-free brazing filler metal alloy for soft brazing of aluminum and aluminum alloy. The tin-based lead-free solder alloy comprises, by mass, 0.8-1.0% of aluminum, 3-4% of zinc, 1.5-3.5% of copper, 0.05-0.1% of titanium and the balance of tin. According to the invention, a proper amount of alloy elements Al, Zn, Cu and Ti are added into the metal tin to form the brazing alloy, the dissolving amount of a base metal in brazing is reduced, the brazing alloy has good wetting spreadability and oxidation resistance, and a brazed aluminum alloy joint has good corrosion resistance.
Description
Technical Field
The invention belongs to the field of brazing materials, and particularly relates to a tin-based lead-free brazing filler metal alloy for soft soldering of aluminum and aluminum alloy.
background
The aluminum and the aluminum alloy have the advantages of high specific strength, good corrosion resistance, good electric and thermal conductivity, good machining performance, relatively low price and the like, and are widely applied to the fields of automobiles, electronics, aerospace and the like. The brazing is an important one in an aluminum alloy connection mode, the brazing heating temperature is low, the welding thermal deformation is small, and the size precision of a weldment is high. With the implementation of the directive RoHS and WEEE in the european union, lead-free has been a global trend. The application and popularization of aluminum alloy lead-free soldering requires a lead-free solder with good soldering process performance and soldered joint reliability.
However, studies on tin-based lead-free solders such as Sn-Cu, Sn-Ag-Cu, and Sn-Zn, which are commonly used in the market, are mainly based on the study of soldering a Cu substrate, and when a copper substrate is soldered with a Sn-based solder, a CuSn or CuZn intermetallic compound is formed at the soldering interface, and the interface bonding is good. When an Al substrate is brazed, Sn and Al do not form intermetallic compounds, the interface bonding force is weak, the electrode potential difference of tin and aluminum is too large, the corrosion resistance of a brazed joint is poor, and the formula of the tin-based lead-free solder alloy for brazing aluminum and aluminum alloy needs to be improved so as to solve some problems in brazing aluminum and aluminum alloy. The present-day research on tin-based lead-free solders for brazing of aluminum and aluminum alloys is as follows:
Brazing aluminum and aluminum alloy using Sn-Ag-Cu brazing filler metal
The research shows that the Sn-Ag-Cu can form an intermetallic compound Ag 2 Al on the side of a brazing interface deviated to a brazing material, the higher the Ag content is (0.5-3.5 wt%), the thinner and continuous intermetallic compound layer is, the closer to the interface, the better the corrosion resistance of a brazed joint is, and the higher the strength is.
Sn-Zn brazing filler metal brazing aluminum and aluminum alloy
The Sn-Zn brazing filler metal brazing aluminum and the aluminum alloy are researched more, because the strength of the Sn-Zn brazing filler metal brazing aluminum alloy is higher, Al-Zn-Sn solid solution is formed at the interface of the Sn-Zn brazing filler metal and the Al alloy, and needle-shaped Al-Sn-Zn solid solution whiskers grow into the brazing filler metal in a protruding mode on certain interface points of an Al substrate, so that the combination of a needle material and a base material is strengthened. However, Sn-Zn solder is easy to oxidize at high temperature, the oxidation resistance is poor, the corrosion resistance of a soldered joint is also poor, and the Sn-Zn solder soldered aluminum alloy with high Zn content can cause the problem of corrosion of a base metal. Most of the current researches are based on Sn-9Zn eutectic solder, and the Zn content in the solder is very high (> 4%). The study of solder alloys with low Zn content (< 4%), high Cu content (> 1.0%), high Al content (> 0.8%) and trace Ti has not been reported.
Disclosure of Invention
Aiming at the defects and shortcomings of the prior art, the invention aims to provide a tin-based lead-free solder alloy for soldering aluminum and aluminum alloy. The electrode potential difference between the brazing alloy and aluminum is small, intermetallic compounds are formed near the interface of the brazing alloy and a base material, the corrosion resistance of a joint is improved, the interface combination of a brazed joint is good, the strength of the brazed joint is high, the dissolution amount of the base material during brazing is low, and the cost of the brazing alloy is low.
The purpose of the invention is realized by the following technical scheme:
A tin-base lead-free solder alloy for soldering aluminium and its alloy is prepared from Sn, Al, Zn, Cu and Ti.
Preferably, the tin-based lead-free solder alloy comprises, by mass, 0.8% -1.0% of aluminum, 3% -4% of zinc, 1.5% -3.5% of copper, 0.05% -0.1% of titanium, and the balance tin.
Preferably, the tin-based lead-free solder alloy comprises the following components, by mass, 1% of aluminum, 4% of zinc, 2.5% of copper, 0.1% of titanium, and the balance tin.
Preferably, the tin-based lead-free solder alloy comprises, by mass, 0.8% of aluminum, 3% of zinc, 3.5% of copper, 0.05% of titanium, and the balance tin.
Preferably, the tin-based lead-free solder alloy comprises, by mass, 0.8% of aluminum, 4% of zinc, 1.5% of copper, 0.1% of titanium, and the balance tin.
The principle of the invention is as follows:
Al: the eutectic point of the Sn-Al binary alloy is Sn-0.6Al, Al alloy elements are added, the dissolving amount of a base material during brazing can be reduced, and the electrode potential of the brazing filler metal can be reduced by the Al alloy elements, so that the electrode potential difference between the brazing filler metal and the base material is reduced, and the corrosion resistance of the aluminum and aluminum alloy brazed joint is improved. However, too high Al content reduces the wet spreadability of the solder and Al-rich phases coarsen. The preferred aluminum content of the present invention is 0.8% to 1.0%.
Zn: the eutectic point of the Sn-Zn binary alloy is Sn-9Zn, the solid solubility of Zn and Al is high, the Zn-containing brazing filler metal forms an Al-Zn-Sn solid solution on a brazing interface, the brazing filler metal is well combined with an Al matrix interface, and the strength of a brazed joint is improved. However, Sn-Zn with high Zn content has poor oxidation resistance, a coarse needle-shaped Zn-rich phase exists in the brazing filler metal, the corrosion resistance of the Zn-rich phase is poor, the corrosion resistance of a brazed joint is further reduced, and the Zn content in the brazing filler metal is controlled. The preferable Zn content of the invention is 3-4%.
Cu is added into the brazing filler metal and can form an AlCu intermetallic compound with Al alloy elements in the brazing filler metal, the intermetallic compound is used as a strengthening phase and can improve the mechanical property of the brazing filler metal, a layer of discontinuous Al 2 Cu intermetallic compound can be formed on the brazing filler metal side of a brazing interface during brazing, and the intermetallic compound can block the flow of electrons in the electrochemical corrosion process, so that the corrosion resistance of the brazing filler metal can be improved.
Ti: a small amount of Ti alloy elements do not form intermetallic compounds with Sn, but can improve the oxidation resistance of the solder, and Ti can refine the microstructure of the solder and improve the mechanical property of the solder. Too high a Ti content causes an increase in the melting point of the brazing filler metal, an increase in the melting range, and a decrease in the wet spreadability of the brazing filler metal. The preferable Ti content of the invention is 0.05-0.1%.
the tin-based lead-free solder alloy has the following advantages and beneficial effects:
(1) The brazing filler metal has small dissolution of base metal during brazing, Al 2 Cu intermetallic compound can be formed on a brazing interface, and a brazed joint has high corrosion resistance.
(2) The interface of the brazing filler metal and the base metal is firmly combined, and the strength of a brazed joint is high.
(3) The brazing filler metal has good wetting and spreading properties when brazing aluminum and aluminum alloy.
(4) The brazing filler metal does not contain noble metal elements, and the cost of the brazing filler metal is low.
(5) The brazing filler metal is suitable for brazing various aluminum alloys, can be prepared into rod-shaped, strip-shaped, thread-shaped, paste-shaped and the like, and can be used for various brazing methods such as flame brazing, furnace brazing, reflow soldering, dip brazing and the like.
Drawings
FIG. 1 is a schematic view of a scanning electron microscope showing a bonding interface between a brazing material and a base material obtained in a comparative example.
FIG. 2 is a schematic view of a scanning electron microscope showing a bonding interface between the brazing material obtained in example 1 and a base material.
Detailed Description
the present invention will be described in further detail with reference to examples, but the embodiments of the present invention are not limited thereto.
comparative example
The tin-based lead-free solder alloy of the comparative example comprises the following components in percentage by mass, copper content is 4.0%, and the balance is tin. The preparation method comprises the following steps:
The raw materials of pure Sn (99.95%) and Cu (99.95%) are adopted, 500g of solder alloy is prepared according to the components shown in the table 1, the solder alloy is placed in a crucible, smelted in an electric furnace, LiCl and KCl eutectic salt is adopted as a covering agent, the heating temperature is 700 ℃, the temperature is kept for 30min, and then the solder alloy is poured into a mold for molding, so that the tin-based lead-free solder alloy of the comparative example is obtained.
Example 1
In the tin-based lead-free solder alloy of the embodiment, the components include, by mass, 1.0% of aluminum, 4.0% of zinc, 2.5% of copper, 0.1% of titanium, and the balance tin. The preparation method comprises the following steps:
The raw materials are pure Sn (99.95%), Al (99.9%), Zn (99.99%), Cu (99.95%) and Sn-1Ti intermediate alloy, 500g of solder alloy is prepared according to the components in the table 1, the solder alloy is placed in a crucible and smelted in an electric furnace, LiCl and KCl eutectic salt is used as a covering agent, the heating temperature is 700 ℃, the heat preservation is carried out for 30min, the mixture is stirred once every 10min and poured into a mold for molding, and the tin-based lead-free solder alloy of the embodiment is obtained.
Example 2
In the tin-based lead-free solder alloy of the embodiment, the components include, by mass, 0.8% of aluminum, 3.0% of zinc, 3.5% of copper, 0.05% of titanium, and the balance tin. The preparation method comprises the following steps:
The raw materials are pure Sn (99.95%), Al (99.9%), Zn (99.99%), Cu (99.95%) and Sn-1Ti intermediate alloy, 500g of solder alloy is prepared according to the components in the table 1, the solder alloy is placed in a crucible and smelted in an electric furnace, LiCl and KCl eutectic salt is used as a covering agent, the heating temperature is 700 ℃, the heat preservation is carried out for 30min, the mixture is stirred once every 10min and poured into a mold for molding, and the tin-based lead-free solder alloy of the embodiment is obtained.
Example 3
In the tin-based lead-free solder alloy of the embodiment, the components include, by mass, 0.8% of aluminum, 4.0% of zinc, 1.5% of copper, 0.1% of titanium, and the balance tin. The preparation method comprises the following steps:
The raw materials are pure Sn (99.95%), Al (99.9%), Zn (99.99%), Cu (99.95%) and Sn-1Ti intermediate alloy, 500g of solder alloy is prepared according to the components in the table 1, the solder alloy is placed in a crucible and smelted in an electric furnace, LiCl and KCl eutectic salt is used as a covering agent, the heating temperature is 700 ℃, the heat preservation is carried out for 30min, the mixture is stirred once every 10min and poured into a mold for molding, and the tin-based lead-free solder alloy of the embodiment is obtained.
Table 1 lead-free solder alloy chemistry (wt.%)
The soldering performance of the tin-based lead-free solder alloy obtained by the invention is tested as follows:
(1) And (3) testing a brazing interface: on a heating table at 300 ℃, 1060 aluminum was brazed with a flux specific for aluminum. Fig. 1 and 2 are schematic views of scanning electron microscopes of bonding interfaces between the brazing material and the base material obtained in comparative example and example 1, respectively.
As can be seen from FIGS. 1 and 2, Al 2 Cu intermetallic compounds can be formed on the solder side of the soldering interface by using Sn-4Cu of the comparative example and the solder in the embodiment, but when the Sn-4Cu solder is used for soldering 1060 aluminum, the Al 2 Cu intermetallic compounds are 60-70 μm away from the soldering interface and are far away from the soldering interface, so that the influence on the performance of the soldering joint is very small, while when the solder is used for soldering 1060 aluminum, the Al 2 Cu intermetallic compounds are only about 10 μm away from the soldering interface and the distance is greatly reduced, so that the corrosion resistance of the soldering joint interface is effectively improved, and the corrosion resistance of the soldering joint is improved.
(2) And (3) testing the spreading area, namely preparing the brazing filler metal into 0.2g of small blocks, polishing 1060 aluminum substrates, soaking the aluminum substrates in 10% NaOH for 15s to remove surface oxide films, neutralizing the aluminum substrates with 5% HNO 3, ultrasonically cleaning the aluminum substrates with alcohol, then air-drying the aluminum substrates, placing 0.2g of small blocks of brazing filler metal on the aluminum substrates, dripping a certain drop of commercial aluminum brazing flux, placing the aluminum brazing flux on a heating table at 300 ℃ for 60s, and calculating the spreading area by using software, wherein the result is shown in table 2.
(3) And (3) testing the corrosion resistance of the soldered joint: 1060Al pieces with a solder joint of 3X 1mm were lap-welded to 1060Al pieces with a solder joint of 20X 1 mm. The pre-welding treatment of 1060 aluminum substrate was the same as the spreading area experiment, 0.08g of solder was used, the solder was brazed at 300 ℃, the joints were immersed in 3.5 wt.% NaCl solution after the solder, until the joints failed by fracture, and the fracture time was recorded, the results are shown in table 2.
(4) The melting point and melting interval temperature of the solder alloy are measured by a differential scanning calorimeter, 20mg of sample for experiment is adopted, the temperature of the instrument is calibrated by pure In, Ar gas is introduced for protection during measurement, the heating rate is 10k/min, and the result is shown In table 2.
TABLE 2 leadless solder alloy properties
as can be seen from the results in Table 2, the solder alloy of the invention has better wetting spreadability than Sn-4Cu, and the wetting spreadability area is improved by 9.7-23.8%. Because the Cu content in the solder is reduced, the melting temperature of the solder is reduced by adding Zn, and the oxidation resistance of the solder is improved by adding a small amount of Ti.
In addition, when the Sn-4Cu brazing filler metal is brazed, the amount of Al 2 Cu intermetallic compounds formed in the brazing filler metal is much larger than that of the intermetallic compounds in the brazing filler metal of the invention, which shows that a large amount of base material 1060Al is dissolved into the brazing filler metal during brazing, and the data of the amount of base material dissolution and thinning shown in Table 2 also prove that when the brazing filler metal with the components of the invention is brazed with 1060Al, the intermetallic compounds formed near the interface effectively prevent the base material from further diffusion and dissolution, and effectively reduce the amount of base material dissolution during brazing filler metal.
The above embodiments are preferred embodiments of the present invention, but the present invention is not limited to the above embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be construed as equivalents thereof, and all such changes, modifications, substitutions, combinations, and simplifications are intended to be included in the scope of the present invention.
Claims (3)
1. A tin-based lead-free solder alloy for soft soldering of aluminum and its alloys, characterized in that: the tin-based lead-free solder alloy comprises, by mass, 0.8-1.0% of aluminum, 4% of zinc, 1.5-3.5% of copper, 0.05-0.1% of titanium and the balance of tin.
2. a tin-based lead-free solder alloy for soldering of aluminum and its alloys according to claim 1, characterized in that: the tin-based lead-free solder alloy comprises the following components, by mass, 1.0% of aluminum, 4% of zinc, 2.5% of copper, 0.1% of titanium and the balance of tin.
3. A tin-based lead-free solder alloy for soldering of aluminum and its alloys according to claim 1, characterized in that: the tin-based lead-free solder alloy comprises, by mass, 0.8% of aluminum, 4% of zinc, 1.5% of copper, 0.1% of titanium and the balance of tin.
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| CN201711323580.8A CN107999996B (en) | 2017-12-13 | 2017-12-13 | tin-base lead-free solder alloy for soft soldering of aluminum and aluminum alloy |
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000141078A (en) * | 1998-09-08 | 2000-05-23 | Nippon Sheet Glass Co Ltd | Leadless solder |
| CN1304344A (en) * | 1999-03-16 | 2001-07-18 | 日本板硝子株式会社 | Leadless solder |
| CN1313802A (en) * | 1999-06-11 | 2001-09-19 | 日本板硝子株式会社 | Lead-free solder |
| CN101007374A (en) * | 2007-01-18 | 2007-08-01 | 广州有色金属研究院 | Lead-free welding flux alloy suitable for dissimilar metals soldering flux of aluminum and copper |
| CN102814595A (en) * | 2012-05-05 | 2012-12-12 | 大连理工大学 | Sn-Zn based near-eutectic lead-free solder alloy for aluminum-bronze soft soldering and preparation method |
| CN103038020A (en) * | 2010-06-28 | 2013-04-10 | 住友金属矿山股份有限公司 | Pb-free solder alloy |
| WO2015004467A2 (en) * | 2013-07-10 | 2015-01-15 | Cambridge Enterprise Limited | Materials and methods for soldering, and soldered products |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20130029178A1 (en) * | 2011-07-27 | 2013-01-31 | Shih-Ying Chang | Active solder |
-
2017
- 2017-12-13 CN CN201711323580.8A patent/CN107999996B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000141078A (en) * | 1998-09-08 | 2000-05-23 | Nippon Sheet Glass Co Ltd | Leadless solder |
| CN1304344A (en) * | 1999-03-16 | 2001-07-18 | 日本板硝子株式会社 | Leadless solder |
| CN1313802A (en) * | 1999-06-11 | 2001-09-19 | 日本板硝子株式会社 | Lead-free solder |
| CN101007374A (en) * | 2007-01-18 | 2007-08-01 | 广州有色金属研究院 | Lead-free welding flux alloy suitable for dissimilar metals soldering flux of aluminum and copper |
| CN103038020A (en) * | 2010-06-28 | 2013-04-10 | 住友金属矿山股份有限公司 | Pb-free solder alloy |
| CN102814595A (en) * | 2012-05-05 | 2012-12-12 | 大连理工大学 | Sn-Zn based near-eutectic lead-free solder alloy for aluminum-bronze soft soldering and preparation method |
| WO2015004467A2 (en) * | 2013-07-10 | 2015-01-15 | Cambridge Enterprise Limited | Materials and methods for soldering, and soldered products |
Non-Patent Citations (1)
| Title |
|---|
| Sn-Zn-Cu-Al无铅钎料的组织及性能分析;李继超等;《重庆理工大学学报(自然科学)》;20120229;第26卷(第2期);第64-70页 * |
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