An antioxidant soldering tin bar and a preparation method thereof

Abstract

This application discloses an antioxidant solder bar and its preparation method, relating to the field of solder materials. Antioxidant solder bars include Sn-Ag-Cu alloy, Bi, Ge, P, and Sn-Be-Sb ternary alloy. In the Sn-Ag-Cu alloy, Sn accounts for 96.5-98.5% by weight, Ag accounts for 1-1.5% by weight, and copper accounts for 0.5-2% by weight. The Bi content is 0.01-0.05% of the Sn-Ag-Cu alloy, the Ge content is 0.01-0.06% of the Sn-Ag-Cu alloy, and the P content is 0.05-0.1% of the Sn-Ag-Cu alloy. The Sn-Be-Sb ternary alloy has a content of 1.2-1.8% of the Sn-Ag-Cu alloy. In the Sn-Be-Sb ternary alloy, Be accounts for 4.8-5.6% by weight, Sb accounts for 2.5-3.8% by weight, and Sn is the balance. The anti-oxidation solder bar of this application has the advantages of good anti-oxidation properties, good spreadability, and high tensile strength.

Description

Technical Field

[0001] This application relates to the field of solder materials, and in particular to an antioxidant solder bar and its preparation method. Background Technology

[0002] In many fields such as electronics manufacturing and precision instrument assembly, welding is a crucial step in connecting components, and solder bars, as the core material in the welding process, directly affect the quality and reliability of the product. With continuous technological advancements, the demand for miniaturization and high performance in electronic products is increasing, placing ever more stringent requirements on welding quality.

[0003] Traditional solder bars have gradually revealed numerous problems in practical use. On the one hand, their spread coefficient is not ideal, making it difficult for the solder to evenly cover the soldering surface during the soldering process. This easily leads to defects such as cold solder joints and missing solder joints, which greatly affects the mechanical strength and electrical connection stability of the solder joints. For example, in the soldering of some micro-electronic components, due to uneven spread, the tiny solder joints cannot form a good alloy layer. In subsequent use, even slight external forces or temperature changes can cause the solder joints to crack and fail.

[0004] On the other hand, poor oxidation resistance is another drawback of traditional solder bars. In the high-temperature environment of soldering, solder readily reacts with oxygen in the air to form an oxide film. This not only hinders good fusion between the solder and the workpiece, reducing soldering quality, but also wastes solder and increases production costs. Furthermore, oxidized solder residue adheres to the area around the solder joint, making it difficult to clean. If it remains inside electronic products, it may cause short circuits and other malfunctions, seriously affecting the long-term reliability and stability of the product.

[0005] Furthermore, insufficient tensile strength makes solder joints prone to breakage under mechanical stress. This is especially true in electronic device connections that require frequent plugging and unplugging, vibration, or exposure to external forces, such as computer motherboard interfaces and mobile phone charging ports. If the solder has poor tensile strength and a short fatigue life, the solder joints at the interface will break after a period of use, leading to connection failure and directly affecting the normal operation of the equipment.

[0006] Given the shortcomings of traditional solder bars, the industry urgently needs a solder bar that can effectively solve the problems of spread coefficient, oxidation resistance and tensile properties. Summary of the Invention

[0007] In order to obtain a solder bar that has good oxidation resistance, good spreadability and high tensile strength, this application provides an anti-oxidation solder bar and a method for preparing the same.

[0008] Firstly, the anti-oxidation solder bar provided in this application adopts the following technical solution:

[0009] An anti-oxidation solder bar comprises a Sn-Ag-Cu alloy and other additives. In the Sn-Ag-Cu alloy, Sn accounts for 96.5-98.5% by weight, Ag accounts for 1-1.5% by weight, and copper accounts for 0.5-2% by weight. The other additives include Bi, Ge, P, and a Sn-Be-Sb ternary alloy, wherein the Bi content is 0.01-0.05% of the Sn-Ag-Cu alloy. The doping amount of Ge is 0.01-0.06% of the Sn-Ag-Cu alloy, the doping amount of P is 0.05-0.1% of the Sn-Ag-Cu alloy, and the doping amount of Sn-Be-Sb ternary alloy is 1.2-1.8% of the Sn-Ag-Cu alloy. In the Sn-Be-Sb ternary alloy, the weight percentage of Be is 4.8-5.6%, the weight percentage of Sb is 2.5-3.8%, and Sn is the balance.

[0010] In this application, the anti-oxidation solder bar is made from a specific ratio of Sn-Ag-Cu alloy, Bi, Ge, P, and a Sn-Be-Sb ternary alloy. The Sn-Be-Sb ternary alloy is made from a specific ratio of tin, beryllium, and antimony. Unlike solder bars made from traditional Sn-Ag-Cu alloys, this application also incorporates Bi, Ge, P, and the Sn-Be-Sb ternary alloy. Through the synergistic effect of these raw materials, the anti-oxidation performance of the solder bar can be improved, reducing the formation of oxide layers and maintaining smoothness and aesthetics. Simultaneously, it also yields an anti-oxidation solder bar with excellent fluidity, good spreadability, and the ability to perform low-temperature (180℃-200℃) soldering while maintaining good soldering results and tensile strength.

[0011] It should be noted that the proportions of each raw material play a crucial role in obtaining an anti-oxidation solder bar with good oxidation resistance, good spreadability, and high tensile strength, and the proportions of each raw material should not exceed the ranges mentioned above in this application. Furthermore, compared with directly incorporating Be and Sb, incorporating Be and Sb in the form of a Sn-Be-Sb ternary alloy can effectively improve the tensile strength and oxidation resistance of the anti-oxidation solder bar.

[0012] In some preferred embodiments, the Sn-Ag-Cu alloy contains 97-97.5% Sn by weight, 1-1.5% Ag by weight, and 1-2% copper by weight.

[0013] In some preferred embodiments, the amount of Bi incorporated is 0.03-0.05% of the Sn-Ag-Cu alloy, the amount of Ge incorporated is 0.04-0.06% of the Sn-Ag-Cu alloy, the amount of P incorporated is 0.05-0.06% of the Sn-Ag-Cu alloy, and the amount of Sn-Be-Sb ternary alloy incorporated is 1.2-1.5% of the Sn-Ag-Cu alloy.

[0014] In some preferred embodiments, in the Sn-Be-Sb ternary alloy, the weight percentage of Be is 5.0-5.2%, the weight percentage of Sb is 2.8-3.2%, and Sn is the balance.

[0015] In this application, the proportions of each raw material are preferred, and the weight percentage of Be in the Sn-Be-Sb ternary alloy is controlled to be 5.0-5.2%, the weight percentage of Sb is 2.8-3.2%, and Sn is the balance. This can further improve the spreading coefficient, anti-oxidation performance, and tensile properties of the anti-oxidation solder bar, which is beneficial to improving the welding quality of the anti-oxidation solder bar.

[0016] In some specific embodiments, the preparation method of the Sn-Be-Sb ternary alloy includes the following steps:

[0017] S1. After melting Sn in an inert gas environment at 240-250℃, the temperature is raised to 350-360℃, Sb and Be are added, and the mixture is stirred and melted evenly to obtain the molten material.

[0018] S2. The molten material is poured into a mold and cooled to obtain a Sn-Be-Sb ternary alloy.

[0019] In some preferred embodiments, S1, Sn is melted in an inert gas environment at 240-250°C, then heated to 350-360°C, Sb and Be are added, stirred and melted evenly, and then cooled to 200-220°C and held for 0.5-1h to obtain the molten material.

[0020] In this application, when preparing the Sn-Be-Sb ternary alloy, adding a step of cooling to 200-220℃ and holding for 0.5-1h can further improve the spreading coefficient, anti-oxidation performance, and tensile properties of the anti-oxidation solder bar, which is beneficial to improving the welding quality of the anti-oxidation solder bar.

[0021] Secondly, the preparation method of the antioxidant solder bar provided in this application adopts the following technical solution:

[0022] A method for preparing an antioxidant solder bar includes the following steps:

[0023] 1. The Sn-Ag-Cu alloy is put into a vacuum melting furnace and melted uniformly under nitrogen protection. Then Bi, Ge, P and Sn-Be-Sb ternary alloy are added and stirred to melt uniformly to obtain a molten liquid.

[0024] 2. The molten liquid is cast and extruded to obtain an antioxidant solder bar.

[0025] In some preferred embodiments, in (1), the melting temperature is controlled at 315-325°C.

[0026] In this application, the melting temperature is controlled at 315-325℃, which is conducive to the uniform fusion of various raw materials and promotes the welding performance of the anti-oxidation solder bar.

[0027] In summary, this application includes at least the following beneficial technical effects:

[0028] (1) Unlike traditional Sn-Ag-Cu alloy solder bars, this application also incorporates Bi, Ge, P and Sn-Be-Sb ternary alloys. Through the combined effect of the raw materials, the anti-oxidation performance of the solder bar can be improved, the formation of oxide layer can be reduced, and the smoothness and aesthetics can be maintained. At the same time, it can also obtain an anti-oxidation solder bar with good fluidity, good spreadability, and the ability to perform low-temperature (180℃-200℃) soldering while maintaining good soldering effect and tensile strength.

[0029] (2) In this application, the proportion of each raw material is preferred, and the weight percentage of Be in the Sn-Be-Sb ternary alloy is controlled to be 5.0-5.2%, the weight percentage of Sb is 2.8-3.2%, and Sn is the balance. This can further improve the spreading coefficient, anti-oxidation performance and tensile properties of the anti-oxidation solder bar, which is beneficial to improving the welding quality of the anti-oxidation solder bar. Detailed Implementation

[0030] The following section provides further explanation of this application in conjunction with specific experiments.

[0031] Example

[0032]

Example 1

[0033] An anti-oxidation solder bar includes a Sn-Ag-Cu alloy and other additives. In the Sn-Ag-Cu alloy, Sn accounts for 96.5% by weight, Ag accounts for 1.5% by weight, and copper accounts for 2% by weight. The other additives include Bi, Ge, P, and a Sn-Be-Sb ternary alloy. Specifically, Bi is incorporated at 0.01% of the Sn-Ag-Cu alloy, Ge at 0.06% by weight, P at 0.05% by weight, and the Sn-Be-Sb ternary alloy at 1.8% by weight. Furthermore, in the Sn-Be-Sb ternary alloy, Be accounts for 4.8% by weight, Sb at 3.8% by weight, and Sn at 91.4% by weight. The preparation method of the Sn-Be-Sb ternary alloy includes the following steps:

[0034] S1. Melt 91.4 kg Sn in an inert gas environment at 250 °C, then heat to 350 °C, add 3.8 kg Sb and 4.8 kg Be, stir and melt evenly to obtain the molten material;

[0035] S2. Pour the molten material into a mold and cool it to obtain the Sn-Be-Sb ternary alloy.

[0036] In this embodiment, the preparation method of the antioxidant solder bar includes the following steps:

[0037] (1) The Sn-Ag-Cu alloy is put into a vacuum melting furnace and melted uniformly at 315°C under nitrogen protection. Then Bi, Ge, P and Sn-Be-Sb ternary alloy are added and stirred and melted uniformly to obtain a molten liquid.

[0038] (2) Cast and extrude the molten liquid to obtain an antioxidant solder bar.

[0039]

Example 2

[0040] An anti-oxidation solder bar includes a Sn-Ag-Cu alloy and other additives. In the Sn-Ag-Cu alloy, Sn accounts for 98.5% by weight, Ag accounts for 1% by weight, and copper accounts for 0.5% by weight. The other additives include Bi, Ge, P, and a Sn-Be-Sb ternary alloy. Specifically, Bi is incorporated at 0.05% of the Sn-Ag-Cu alloy, Ge at 0.01% of the Sn-Ag-Cu alloy, P at 0.1% of the Sn-Ag-Cu alloy, and the Sn-Be-Sb ternary alloy at 1.2% of the Sn-Ag-Cu alloy. Furthermore, in the Sn-Be-Sb ternary alloy, Be accounts for 5.6% by weight, Sb at 2.5% by weight, and Sn at 91.9% by weight. The preparation method of the Sn-Be-Sb ternary alloy includes the following steps:

[0041] S1. Melt 91.9 kg Sn in an inert gas environment at 240 °C, then heat to 360 °C, add 2.5 kg Sb and 5.6 kg Be, stir and melt evenly to obtain the molten material;

[0042] S2. Pour the molten material into a mold and cool it to obtain the Sn-Be-Sb ternary alloy.

[0043] In this embodiment, the preparation method of the antioxidant solder bar includes the following steps:

[0044] (1)(1) The Sn-Ag-Cu alloy is put into a vacuum melting furnace and melted uniformly at 325°C under nitrogen protection. Then Bi, Ge, P and Sn-Be-Sb ternary alloy are added and stirred and melted uniformly to obtain a molten liquid.

[0045] (2) Cast and extrude the molten liquid to obtain an antioxidant solder bar.

[0046]

Example 3

[0047] An anti-oxidation solder bar includes a Sn-Ag-Cu alloy and other additives. In the Sn-Ag-Cu alloy, Sn accounts for 97.2% by weight, Ag accounts for 1.3% by weight, and copper accounts for 1.5% by weight. The other additives include Bi, Ge, P, and a Sn-Be-Sb ternary alloy. The Bi content is 0.04% of the Sn-Ag-Cu alloy, the Ge content is 0.05% of the Sn-Ag-Cu alloy, the P content is 0.055% of the Sn-Ag-Cu alloy, and the Sn-Be-Sb ternary alloy content is 1.35% of the Sn-Ag-Cu alloy. In the Sn-Be-Sb ternary alloy, Be accounts for 5.1% by weight, Sb accounts for 3.0% by weight, and Sn accounts for 91.9% by weight.

[0048] In this embodiment, the preparation method of Sn-Be-Sb ternary alloy and the preparation method of anti-oxidation solder bar are consistent with those in [Example 1].

[0049]

Example 4

[0050] An antioxidant solder bar differs from [Example 3] in that the preparation method of the Sn-Be-Sb ternary alloy is different. In this example, the preparation method of the Sn-Be-Sb ternary alloy includes the following steps:

[0051] S1. 91.9 kg Sn was melted at 250 °C in an inert gas environment, then heated to 350 °C, 3.0 kg Sb and 5.1 kg Be were added, and the mixture was stirred until it was uniformly melted. Then the temperature was lowered to 210 °C and kept at that temperature for 0.5 h to obtain the molten material.

[0052] S2. Pour the molten material into a mold and cool it to obtain the Sn-Be-Sb ternary alloy.

[0053] Comparative Example

[0054] Comparative Example 1

[0055] A solder bar differs from [Example 1] in that it does not contain a Sn-Be-Sb ternary alloy, but instead contains equal amounts of Sn, Be, and Sb.

[0056] Comparative Example 2

[0057] A solder bar that differs from [Example 1] in that it does not contain P.

[0058] Comparative Example 3

[0059] A solder bar that differs from [Example 1] in that it does not contain Bi and Ge.

[0060] Performance testing

[0061] (1) Spreading coefficient: The spreading coefficient of the solder bars prepared in each embodiment and comparative example was tested in accordance with GB / T 11364-89 "Test method for spreadability and filler properties of solder". The spreading substrate was a 0.2mm thick pure copper plate, the test temperature was 400℃, and the test time was 10s. The larger the spreading coefficient, the better the wettability of the solder bar, which is beneficial to improving the soldering strength of the solder bar.

[0062] (2) Antioxidant properties: The solder bars prepared in each example and comparative example were melted at 250℃, 400℃ and 550℃ respectively and kept at that temperature for 24 hours. Then, the oxide film on the surface of the liquid solder was scraped off, cooled to room temperature, and the weight of the oxide film was measured. In each test, the test weight of the solder bar was 100g. The less oxide film produced, the better the antioxidant properties of the solder bar.

[0063] (3) Tensile strength: The tensile strength of the solder bars prepared in each embodiment and comparative example was tested in accordance with GB / T 228.1-2021 "Metallic materials - Tensile testing - Part 1: Room temperature test method". The higher the tensile strength, the more beneficial it is to improve the stability of the welded joint.

[0064] Table 1

[0065]

[0066]

[0067] Based on the above examples 1 and comparative examples 1-3, as well as the test data in Table 1, it can be seen that Sn-Be-Sb ternary alloy, P, Bi, and Ge all play a key role in improving the oxidation resistance of solder bars. In addition, the addition of Sn-Be-Sb ternary alloy can further improve the tensile strength of solder bars, which is beneficial to improving the stability of the welded joint.

[0068] Based on the above Examples 1 and 3 and the test data in Table 1, it can be seen that by optimizing the ratio of each raw material, the spreading coefficient, anti-oxidation performance and tensile properties of the anti-oxidation solder bar can be further improved, which is beneficial to improving the welding quality of the anti-oxidation solder bar.

[0069] Based on the above Examples 3 and 4 and the test data in Table 1, it can be seen that by further optimizing the preparation method of Sn-Be-Sb ternary alloy, the oxidation resistance and tensile properties of the anti-oxidation solder bar can be further improved, which is conducive to further improving the welding quality of the anti-oxidation solder bar.

[0070] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this specific embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. An antioxidant solder bar, characterized in that: The mixture includes a Sn-Ag-Cu alloy and other additives. In the Sn-Ag-Cu alloy, Sn accounts for 96.5-98.5% by weight, Ag accounts for 1-1.5% by weight, and copper accounts for 0.5-2% by weight. The other additives include Bi, Ge, P, and a Sn-Be-Sb ternary alloy. The Bi content is 0.01-0.05% of the Sn-Ag-Cu alloy, the Ge content is 0.01-0.06% of the Sn-Ag-Cu alloy, the P content is 0.05-0.1% of the Sn-Ag-Cu alloy, and the Sn-Be-Sb ternary alloy content is 1.2-1.8% of the Sn-Ag-Cu alloy. In the Sn-Be-Sb ternary alloy, Be accounts for 4.8-5.6% by weight, Sb accounts for 2.5-3.8% by weight, and Sn is the balance. The Sn-Be-Sb ternary alloy is prepared by the following method: S1, Sn is melted in an inert gas environment at 240-250℃, then heated to 350-360℃, Sb and Be are added, stirred and melted evenly, and then cooled to 200-220℃ and held for 0.5-1h to obtain a molten material; S2, the molten material is poured into a mold and cooled to obtain the Sn-Be-Sb ternary alloy.

2. The antioxidant solder bar according to claim 1, characterized in that: In the Sn-Ag-Cu alloy, Sn accounts for 97-97.5% by weight, Ag accounts for 1-1.5% by weight, and copper accounts for 1-2% by weight.

3. The antioxidant solder bar according to claim 1, characterized in that: The amount of Bi incorporated is 0.03-0.05% of the Sn-Ag-Cu alloy, the amount of Ge incorporated is 0.04-0.06% of the Sn-Ag-Cu alloy, the amount of P incorporated is 0.05-0.06% of the Sn-Ag-Cu alloy, and the amount of Sn-Be-Sb ternary alloy incorporated is 1.2-1.5% of the Sn-Ag-Cu alloy.

4. The antioxidant solder bar according to claim 1, characterized in that: In the Sn-Be-Sb ternary alloy, the weight percentage of Be is 5.0-5.2%, the weight percentage of Sb is 2.8-3.2%, and Sn is the balance.

5. A method for preparing an antioxidant solder bar as described in any one of claims 1-4, characterized in that, The process includes the following steps: (1) Sn-Ag-Cu alloy is put into a vacuum melting furnace and melted uniformly under nitrogen protection. Then Bi, Ge, P and Sn-Be-Sb ternary alloy are added and stirred and melted uniformly to obtain a molten liquid; (2) The molten liquid is cast and extruded to obtain an anti-oxidation solder bar.

6. The method for preparing an antioxidant solder bar according to claim 5, characterized in that: (1) The melting temperature is controlled at 315-325℃.

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