阅读说明：本技术 一种vc均热板用低温封装材料及其制备方法及应用 (Low-temperature packaging material for VC vapor chamber and preparation method and application thereof ) 是由 韩启航 易翠 莫文剑 帅歌国 于 2020-04-28 设计创作，主要内容包括：本发明公开了一种VC均热板用低温封装材料、其制备方法及应用。该封装材料包含如下组分：钎料53wt％-94wt％、成膏体6wt％-47wt％以及用量为钎料质量0-9％的钎剂,其中,钎料包含CuB合金,和/或添加一种以上其他合金元素；钎剂包含BaF<Sub>2</Sub>、CaF<Sub>2</Sub>、KF、NaF、丁二酸、癸二酸、月桂酸和硼酸中的任意一种或两种以上的组合；成膏体包含溶剂、增稠剂、流变剂、消泡剂和活化剂。本发明还公开了一种VC均热板用低温封装材料的制备方法。采用本发明的方法制备的封装材料在焊接前的焊膏涂装过程中,焊膏触变性、抗塌陷能力和流动性好,焊接后零件接头强度高,焊缝饱满且无残留物,零件无需清洗,可应用于高功率散热模组和不锈钢零件。(The invention discloses a low-temperature packaging material for a VC soaking plate, and a preparation method and application thereof. The packaging material comprises the following components: 53-94 wt% of brazing filler metal, 6-47 wt% of paste and brazing flux with the amount of 0-9% of the mass of the brazing filler metal, wherein the brazing filler metal comprises CuB alloy and/or is added with more than one other alloy element; the flux contains BaF 2 、CaF 2 Any one or combination of more than two of KF, NaF, succinic acid, sebacic acid, lauric acid and boric acid; the paste-forming body comprises a solvent, a thickener, a rheological agent, a defoamer and an activator. The invention also discloses a preparation method of the low-temperature packaging material for the VC soaking plate. The packaging material prepared by the method has good thixotropy, collapse resistance and fluidity of the soldering paste in the process of coating the soldering paste before welding, high joint strength of parts after welding, full welding line, no residue, no need of cleaning the parts, and applicability to high-power heat dissipation modulesAnd stainless steel parts.)

1. A low-temperature packaging material for a VC soaking plate comprises the following components: 53 to 94 percent of brazing filler metal, 6 to 47 percent of paste and brazing flux with the dosage of 0 to 9 percent of the mass of the brazing filler metal,

the brazing filler metal comprises CuB alloy, B is an essential element, and/or more than one other alloying element is added, and the other alloying element is at least selected from any one of Sn, Ni, P and Zn;

the brazing flux comprises BaF₂、CaF₂Any one or combination of more than two of KF, NaF, succinic acid, sebacic acid, lauric acid and boric acid;

the paste-forming body comprises the following components: 60-98 wt% of solvent, 0.5-8 wt% of thickening agent, 0.2-35 wt% of rheological agent and 0.1-5 wt% of defoaming agent and activating agent.

2. The low-temperature packaging material for the VC soaking plate as claimed in claim 1, wherein the B accounts for 1-3% by weight of the CuB alloy.

3. The low-temperature packaging material for the VC soaking plate as claimed in claim 1, wherein the CuB alloy component is any one or the combination of more than two of the following components:

Cu_{balance of}B_(1-3)；

Cu_{Balance of}B_(1-3)Sn_(13-17)Ni_(3-8)P_(3-8)；

Cu_{Balance of}B_(1-3)Sn_(8-60)；

Cu_{Balance of}B_(1-3)Zn_(30-55)；

Cu_{Balance of}B_(1-3)P_(5-14)；

Wherein the content is weight percentage, and Cu and B are necessary elements.

4. The low-temperature packaging material for the VC soaking plate as claimed in any one of claims 1 to 3, wherein the brazing filler metal further comprises additive powder, and the additive powder is any one or a combination of more than two of 0.5 to 5 wt% of Fe powder, 0.05 to 5 wt% of Ni powder, 0.1 to 5 wt% of Mn powder, 0.05 to 2 wt% of Si powder and 0.05 to 2 wt% of B powder.

5. The VC soaking plate low-temperature packaging material as claimed in any one of claims 1 to 3, wherein CuB alloy and other alloys in the brazing filler metal are atomized metal powder, and the brazing flux is powder.

6. The low-temperature packaging material for the VC soaking plate as claimed in claim 1, wherein the solvent is any one or a combination of more than two of deionized water, diethylene glycol monoethyl ether, dipropylene glycol butyl ether, 1, 2-propylene glycol, carbitol and ethylene glycol.

7. The low-temperature packaging material for VC soaking plates as defined in claim 1, wherein the thickening agent is any one or a combination of two or more of hydroxyethyl starch, hydroxypropyl starch, methyl acrylate, carboxymethyl starch, ethyl hydroxyethyl cellulose, chitin, guar gum, gum arabic and locust bean gum.

8. The low-temperature packaging material for the VC soaking plate as claimed in claim 1, wherein the rheological agent is any one or the combination of more than two of hydrogenated castor oil, modified castor oil, glycerin, stearic acid and deionized water salicylamide.

9. The low-temperature packaging material for the VC soaking plate as claimed in claim 1, wherein the defoaming agent and the activating agent are any one or a combination of more than two of alkyne diol, benzotriazol, silicone oil, mineral oil and vegetable oil.

10. A preparation method of a low-temperature packaging material for a VC soaking plate is characterized by comprising the following steps:

(1) preparing a raw material for the composition of the low-temperature encapsulating material for the VC soaking plate according to any one of claims 1 to 9;

(2) preparing Cu, B or other alloy powder by adopting an air atomization or water atomization method;

(3) uniformly mixing Cu, B or other alloy powder with the addition powder;

(4) adding a thickening agent, a rheological agent, a defoaming agent and an activating agent into a solvent according to a certain proportion and sequence, stirring to form a uniform solution, and forming paste, wherein under the condition that the composition of the packaging material contains a soldering flux, the soldering flux is required to be added into the solvent firstly and stirred uniformly, and then the thickening agent, the rheological agent, the defoaming agent and the activating agent are added into the solution according to the proportion and sequence to form the paste mixed with the soldering flux;

(5) and adding the brazing filler metal into the paste-forming body or the paste-forming body mixed with the brazing flux, and uniformly stirring to obtain the packaging material.

11. Use of a low temperature encapsulant for VC soaking plates as described in any of claims 1-9 or prepared by the method of claim 10 in a soldering process.

Technical Field

The invention relates to a welding material, in particular to a low-temperature packaging material for a VC soaking plate, a preparation method and application thereof.

Background

With the development of high-efficiency mass production of modern industrial automation packaging (soldering), packagingThe (brazing) workpieces are increasingly miniaturized and produced in batches, and the shapes of welding seams are continuously diversified and complicated. The realization of high efficiency automated welding production by replacing traditional wire, ring, strip welding materials with paste welding materials-braze paste has been the trend. China has continuously introduced foreign advanced automatic packaging (brazing) production lines such as a flame automatic brazing production line and a protective atmosphere mesh belt furnace brazing production line in recent years; meanwhile, a plurality of manufacturers independently develop and develop advanced automatic brazing production lines in China to meet the increasing market demands. Compared with the traditional Cu alloy welding wire, welding ring and brazing thin strip, the automatic dispensing device is combined with the packaging material, the automatic coating can be carried out on complex parts and special-shaped parts, and the coated parts to be welded enter a continuous brazing furnace for brazing, so that the continuity and automation of the whole welding process are realized. The welded parts have high joint strength, beautiful welding seams and good corrosion resistance. For example, CN 1298493C discloses a low-temperature packaging material for automatic VC vapor chamber, in which the metal powder (solder) component is Cu,_{balance of}Ni_(0.52-1.0)(wt%, the same below), P (4-8), Sn (4-7), B (0.05-0.9), Ti (0.05-0.5), In (0.05-0.9), rare earth (0.05-0.1); the flux is a mixture of potassium fluoborate and potassium borate with the components of KxByOzFm, and the proportion of the flux to the brazing filler metal is (12-18) to (88-82); the paste forming body (paste forming body) is composed of a polyisobutylene mixture, a C6-C18 organic solvent, nonylphenol polyoxyethylene ether, fatty glyceride, benzotriazol, unsaturated fatty acid and animal and vegetable oil, and the content of the paste forming body in the soldering paste is 5.1-10.1%. The content of the soldering flux in the packaging material is up to more than 10 percent, and the fluoborate has strong corrosivity at high temperature, so that the parts to be welded and soldering equipment can be excessively corroded and damaged, the parts need to be cleaned after being welded, and corrosive volatile matters in the welding process can bring a series of problems to the working environment and environmental protection.

Patent No. ZL200510036064.8 discloses a paste-forming body for solder paste, which is composed of five parts of rheological agent, stabilizer, resin, activator and solvent, and because the soldering temperature of the solder paste is between 150 ℃ and 300 ℃, the paste-forming body must be completely decomposed below the soldering temperature. In the soldering process of the packaging material, the soldering temperature is higher than 1090 ℃, and the temperature for completely decomposing the formed paste is 400-500 ℃, so that the packaging material can form a sintered body with certain strength after the formed paste is volatilized and is attached to a part to be soldered, and therefore, the existing paste forming system for the soldering paste is not suitable for manufacturing the packaging material.

Moreover, the packaging material prepared by the technical scheme has the problems of insufficient packaging strength and corrosion resistance, and particularly when the packaging material is applied to ultrathin soaking plates and stainless steel soaking plates, the defects are more obvious, and the yield of the soaking plates is easily reduced.

Disclosure of Invention

The invention aims to provide a low-temperature packaging material for a VC soaking plate, which aims to solve the problem of insufficient strength and corrosion resistance of the packaging material in the prior art, can obviously improve the strength of the packaging material, and enables alloy purification, grain refinement and packaging strength to be obviously improved in the packaging process of the alloy.

In order to achieve the purpose, the invention adopts the following technical scheme:

a low-temperature packaging material for a VC soaking plate comprises the following components: 53 to 94 percent of brazing filler metal, 6 to 47 percent of paste and brazing flux with the dosage of 0 to 9 percent of the mass of the brazing filler metal,

the brazing filler metal comprises CuB alloy and/or is added with more than one other alloying element, and the other alloying element is at least selected from any one of Sn, Ni, P and Z;

the brazing flux comprises BaF₂、CaF₂Any one or combination of more than two of KF, NaF, succinic acid, sebacic acid, lauric acid and boric acid;

the paste-forming body comprises the following components: 60-98 wt% of solvent, 0.5-8 wt% of thickening agent, 0.2-35 wt% of rheological agent and 0.1-5 wt% of defoaming agent and activating agent.

Preferably, the CuB alloy is any one or a combination of two or more of the following components:

Cu_{balance of}B_(1-3)(weight percent);

Cu_{balance of}B_(1-3)Sn_(13-17)Ni_(3-8)P_(3-8)(weight percent);

Cu_{balance of}B_(1-3)Sn_(8-60)(weight percent);

Cu_{balance of}B_(1-3)Zn_(30-55)(weight percent);

Cu_{balance of}B_(1-3)P_(5-14)(weight percent).

Preferably, the brazing filler metal further comprises any one or a combination of two or more of 0.5 to 5 wt% of Fe powder, 0.05 to 5 wt% of Ni powder, 0.1 to 5 wt% of Mn powder, 0.05 to 2 wt% of Si powder and 0.05 to 2 wt% of B powder.

In a preferred embodiment, the brazing filler metal is an atomized metal powder made of a copper-boron alloy or other alloys, and the brazing flux is a powder.

As one of preferable embodiments, the solvent may be at least any one selected from the group consisting of deionized water, diethylene glycol monoethyl ether, dipropylene glycol monobutyl ether, 1, 2-propylene glycol, carbitol, and ethylene glycol, but is not limited thereto.

As one of preferable embodiments, the thickener may be at least one or a combination of two or more selected from the group consisting of hydroxyethyl starch, hydroxypropyl starch, methyl acrylate, carboxymethyl starch, ethyl hydroxyethyl cellulose, chitin, guar gum, gum arabic, and locust bean gum, but is not limited thereto.

As one of the preferable embodiments, the rheological agent may be at least one selected from the group consisting of hydrogenated castor oil, modified castor oil, glycerin, stearic acid, and deionized water salicylic acid amide, but is not limited thereto.

As one of preferable embodiments, the antifoaming agent and the activator may be at least any one selected from the group consisting of acetylene glycol, benzotriazol, silicone oil, mineral oil and vegetable oil, but not limited thereto. Because the alkyne diol has the functions of activating and defoaming, the alkyne diol can be used as a defoaming agent and an activating agent.

A preparation method of a low-temperature packaging material for a VC soaking plate comprises the following steps:

(1) preparing raw materials according to the composition of the low-temperature packaging material for the VC soaking plate;

(2) preparing Cu, B or alloy powder by adopting an air atomization or water atomization method;

(3) uniformly mixing Cu and B with alloy powder and additive powder;

(4) adding a thickening agent, a rheological agent, a defoaming agent and an activating agent into a solvent according to a certain proportion and sequence, stirring to form a uniform solution, and forming paste, wherein under the condition that the composition of the packaging material contains a soldering flux, the soldering flux is required to be added into the solvent firstly and stirred uniformly, and then the thickening agent, the rheological agent, the defoaming agent and the activating agent are added into the solution according to the proportion and sequence to form the paste mixed with the soldering flux;

(5) and adding the brazing filler metal into the paste-forming body or the paste-forming body mixed with the brazing flux, and uniformly stirring to obtain the packaging material.

The application of the low-temperature packaging material for the VC soaking plate or the low-temperature packaging material for the VC soaking plate prepared by the method in the welding process.

Compared with the prior art, the invention has the advantages that: (1) boron acts as a modifier in the copper alloy and partially serves as a homogeneous nucleation due to the formation of needle-like and bulk phases during or prior to solidification. Meanwhile, boron has low solid solubility in copper, is easy to segregate at a crystal boundary, prevents the growth of crystal grains, reduces the interface energy and plays a role in refining the crystal grains. In addition, boron is deviated and gathered in the grain boundary, and can change the interface energy, which is beneficial to changing the form of a second phase on the grain boundary, so that the second phase is easier to spheroidize, and the grain boundary strength is improved; (2) the boron element also serves as a deoxidizing and degassing agent in the packaging material, so that the welding strength and the corrosion resistance of the packaging material are improved.

Detailed Description

As mentioned above, the present invention aims to provide one or more packaging materials, which, by adding a proper amount of B element into the solder, on one hand, can be used as a deoxidizing and degassing agent, and at the same time, can act as a modifier, thereby significantly improving the strength of the packaging material, and enabling the alloy to be purified, grain refined and packaged during the packaging process.

Furthermore, the packaging material of the invention consists of three parts of brazing filler metal, soldering flux and paste, wherein:

the brazing filler metal is composed of metal powder and/or additive powder, and comprises one or more of Cu (purity is more than 99%), B (1-3%) and/or Cu balance B (1-3%) Sn (13-17%) Ni (3-8%) P (3-8%), Cu balance B (1-3%) Sn (8-15%), Cu balance B (1-3%) Sn (40-60%), Cu balance B (1-3%) Zn (30-55%), and Cu balance B (1-3%) P (5-14%).

The boron element is an essential element of the brazing filler metal, plays an important role in the packaging material, can be used as a deoxidizing and degassing agent, and can obviously improve the strength and the corrosion resistance of the packaging material. Based on experimental research, the boron content of 1-3% (mass fraction) can achieve the best comprehensive effect.

In addition, one or more of Fe powder, Ni powder, Mn powder, Si powder and B powder which are 0.5-5%, 0.05-2% and 0.05-2% of the weight of the brazing filler metal can be added according to the requirements of welding strength and appearance of welding seams.

The amount of solder is preferably 53-94% by weight of the encapsulating material.

The flux is in powder state and contains BaF₂、CaF₂KF, NaF, succinic acid, sebacic acid, lauric acid, and boric acid.

The paste-forming body mainly comprises a solvent, a thickening agent, a rheological agent, a defoaming agent and an activating agent.

The solvent is at least one of deionized water, diethylene glycol monoethyl ether, dipropylene glycol monobutyl ether, 1, 2-propylene glycol, carbitol and ethylene glycol;

the thickener is at least one of hydroxyethyl starch, hydroxypropyl starch, methyl acrylate, carboxymethyl starch, ethyl hydroxyethyl cellulose, chitin, guar gum, acacia and locust bean gum;

the rheological agent is at least one of hydrogenated castor oil, modified castor oil, glycerol, stearic acid and deionized water salicylic acid amide;

the defoaming agent and the activating agent are at least one of acetylene glycol, benzotriazol, silicone oil, mineral oil and vegetable oil; because the alkyne diol has the functions of activating and defoaming, the alkyne diol can be used as a defoaming agent and an activating agent.

The paste forming body accounts for 6-47% of the weight of the packaging material, wherein the solvent accounts for 60-98% of the weight of the paste forming body, the thickener accounts for 0.5-8% of the weight of the paste forming body, the rheological agent accounts for 0.2-35% of the weight of the paste forming body, and the defoaming agent and the activator account for 0.1-5% of the weight of the paste forming body.

It should be noted that, in the present specification, all the percentage contents are weight percentage contents unless otherwise specified.

The technical solution of the present invention is further described below with reference to several preferred embodiments.