Paste forming body for Cu-Sn-Ti solder powderTechnical Field
The invention relates to the technical field of welding, in particular to a paste forming body for Cu-Sn-Ti solder powder.
Background
The cubic boron nitride (cBN) has excellent mechanical property and chemical stability, and is not easy to generate chemical reaction with iron group elements, so that the product is very suitable for processing high-hardness and good-toughness metal materials such as iron-based alloy, nickel-based alloy and titanium alloy. In addition, because of the small size of the cBN abrasive particles, it needs to be consolidated for use. The currently widely used consolidation method is to braze cBN particles through brazing filler metal, thereby realizing connection with higher strength. In a brazing filler metal system for cBN brazing, compared with an Ag-Cu system brazing filler metal, the Cu-Sn-Ti system brazing filler metal has higher strength and better corrosion resistance; compared with nickel-based brazing filler metal, the brazing filler metal has a relatively low melting point, so that the brazing filler metal has the advantage of energy conservation and has low requirements on equipment.
In the actual use process, not only the cBN needs to bear abrasion and corrosion, but also the consolidated brazing filler metal component also has the abrasion and corrosion functions, so that the key for further improving the service performance of the cBN consolidated workpiece is to improve the wear resistance and the corrosion resistance of the brazing filler metal component. In order to further improve the performance of Cu-Sn-Ti based solders, a method of adding hard alloy particles to the solder is generally used, but it is often difficult to achieve an ideal effect of uniform dispersion in the solder.
Disclosure of Invention
The invention aims to solve the technical problem of overcoming the defects in the prior art and provides a paste forming body for Cu-Sn-Ti solder powder.
In order to solve the technical problem, the solution of the invention is as follows:
provides a paste body for Cu-Sn-Ti solder powder, which consists of the following components in percentage by weight:
poly (2-ethyl-2-oxazoline): 15 to 25 percent
Polypropylene carbonate: 0.5 to 5 percent
Soluble starch: 5.5 to 8.5 percent
Aqueous polyurethane emulsion: 30 to 50 percent
Pentaerythritol: 0.25 to 1 percent
Glycerol: 5 to 9 percent of
Deionized water: 10 to 40 percent.
In the present invention, the mass average molecular weight of the poly (2-ethyl-2-oxazoline) is 200000.
In the invention, the mass average molecular weight of the polypropylene carbonate is 500000.
In the invention, the aqueous polyurethane emulsion is Dispercoll U54 type aqueous polyurethane emulsion of Corsia, and the solid content is 50%.
The paste forming body can be prepared by the following method:
(1) weighing the components according to the weight percentage;
(2) adding poly (2-ethyl-2-oxazoline), polypropylene carbonate and glycerol into a mixer, mixing for 2 hours, stopping mixing, and cooling to room temperature to obtain a mixture I;
(3) adding soluble starch and pentaerythritol into deionized water, heating to 100 ℃ while stirring, and continuously stirring until the mixture is completely uniform to obtain a mixture II;
(4) adding the mixture I into the mixture II, manually stirring for 30-60 seconds, and grinding for 10-20 times by using a three-roll grinder until the mixture is completely uniform to obtain a mixture III;
(5) and adding the aqueous polyurethane emulsion into the third mixture, manually stirring for 30-60 seconds, and grinding for 3-6 times by using a three-roll grinder until the mixture is completely uniform to obtain a paste body of the Cu-Sn-Ti solder powder.
In the present invention, the rotation speed of the mixer in the step (2) is 300-800 rpm.
The application method of the paste forming body of the invention comprises the following steps:
and mixing the prepared paste with Cu-Sn-Ti solder powder according to the mass ratio of 15:85 to obtain the paste solder. The paste braze was used for brazing of cBN particles in the amounts required for the normal operation of brazing cBN particles.
Compared with the prior art, the invention has the following beneficial effects:
1. the paste-forming body of the invention can be used for vacuum brazing of cBN consolidation after being mixed with Cu-Sn-Ti brazing filler metal powder to prepare paste-like brazing filler metal. Because the paste formed before the vacuum brazing is uniformly mixed with the Cu-Sn-Ti system brazing filler metal powder to form a paste brazing filler metal system, a small amount of carbon residue formed in the vacuum brazing can react with a Ti component in the brazing filler metal system to form TiC particles which are uniformly dispersed in a brazing filler metal layer after the vacuum brazing. Thereby solving the dispersion problem of the added hard alloy particles and further improving the comprehensive performance of the brazing filler metal layer.
2. The invention realizes the effective control of the carbon residue through the screening of the raw materials and the determination of the optimization of the mixture ratio among the raw materials through a large number of experiments. The paste-forming body provided by the invention has proper carbon residue formed in the vacuum brazing process, and the problem that the performance of the components after vacuum brazing is seriously reduced due to a large number of defects caused by excessive carbon residue is solved.
Detailed Description
The present invention will be described in detail with reference to specific examples. The following examples will assist those skilled in the art in further understanding the invention, but are not intended to limit the invention in any way. It should be noted that variations and modifications can be made by persons skilled in the art without departing from the spirit of the invention. All falling within the scope of the present invention.
Example 1:
the paste forming body for the Cu-Sn-Ti solder powder comprises the following components in percentage by weight:
poly (2-ethyl-2-oxazoline): 15 percent of
Polypropylene carbonate: 5 percent of
Soluble starch: 8.5 percent
Aqueous polyurethane emulsion: 30 percent of
Pentaerythritol: 1 percent of
Glycerol: 9 percent of
Deionized water: 31.5 percent.
The mass average molecular weight of the poly (2-ethyl-2-oxazoline) is 200000, and the mass average molecular weight of the polypropylene carbonate is 500000; the aqueous polyurethane emulsion is Dispercoll U54 type aqueous polyurethane emulsion of Corsia, and the solid content is 50%.
The preparation method of the paste-forming body comprises the following steps:
1. weighing the components according to the weight percentage;
2. adding poly (2-ethyl-2-oxazoline), polypropylene carbonate and glycerol into a high-speed mixer (300 revolutions per minute), mixing for 2 hours, stopping mixing, cooling to room temperature, and taking out the mixture to obtain a mixture I;
3. adding soluble starch and pentaerythritol into deionized water, heating to 100 ℃ while stirring, and continuously stirring until the mixture is completely uniform to obtain a mixture II;
4. adding the mixture I into the mixture II, manually stirring for 30 seconds, and grinding for 10 times by using a three-roll grinder until the mixture is completely uniform to obtain a mixture III;
5. and adding the aqueous polyurethane emulsion into the third mixture, manually stirring for 30 seconds, and grinding for 3 times by using a three-roll grinder until the mixture is completely uniform to obtain a finished paste body of the Cu-Sn-Ti solder powder.
Example 2:
the paste forming body for the Cu-Sn-Ti solder powder comprises the following components in percentage by weight:
poly (2-ethyl-2-oxazoline): 25 percent of
Polypropylene carbonate: 0.5 percent
Soluble starch: 5.5 percent
Aqueous polyurethane emulsion: 50 percent of
Pentaerythritol: 0.25 percent
Glycerol: 5 percent of
Deionized water: 13.75 percent.
The mass average molecular weight of the poly (2-ethyl-2-oxazoline) is 200000, and the mass average molecular weight of the polypropylene carbonate is 500000; the aqueous polyurethane emulsion is Dispercoll U54 type aqueous polyurethane emulsion of Corsia, and the solid content is 50%.
The preparation method of the paste-forming body comprises the following steps:
1. weighing the components according to the weight percentage;
2. adding poly (2-ethyl-2-oxazoline), polypropylene carbonate and glycerol into a high-speed mixer (800 rpm), mixing for 2 hours, stopping mixing, cooling to room temperature, and taking out the mixture to obtain a mixture I;
3. adding soluble starch and pentaerythritol into deionized water, heating to 100 ℃ while stirring, and continuously stirring until the mixture is completely uniform to obtain a mixture II;
4. adding the mixture I into the mixture II, manually stirring for 1 minute, and grinding for 20 times by using a three-roll grinder until the mixture is completely uniform to obtain a mixture III;
5. and adding the aqueous polyurethane emulsion into the third mixture, manually stirring for 1 minute, and grinding for 6 times by using a three-roll grinder until the mixture is completely uniform to obtain a paste body of the Cu-Sn-Ti solder powder.
Example 3:
the paste forming body for the Cu-Sn-Ti solder powder comprises the following components in percentage by weight:
poly (2-ethyl-2-oxazoline): 20 percent of
Polypropylene carbonate: 3 percent of
Soluble starch: 7 percent of
Aqueous polyurethane emulsion: 40 percent of
Pentaerythritol: 0.5 percent
Glycerol: 7 percent of
Deionized water: 22.5 percent.
The mass average molecular weight of the poly (2-ethyl-2-oxazoline) is 200000, and the mass average molecular weight of the polypropylene carbonate is 500000; the polyurethane emulsion is Dispercoll U54 type aqueous polyurethane emulsion with the solid content of 50 percent.
The preparation method of the paste-forming body comprises the following steps:
2. weighing the components according to the weight percentage;
2. adding poly (2-ethyl-2-oxazoline), polypropylene carbonate and glycerol into a high-speed mixer (600 revolutions per minute), mixing for 2 hours, stopping mixing, cooling to room temperature, and taking out the mixture to obtain a mixture I;
3. adding soluble starch and pentaerythritol into deionized water, heating to 100 ℃ while stirring, and continuously stirring until the mixture is completely uniform to obtain a mixture II;
4. adding the mixture I into the mixture II, manually stirring for 45 seconds, and grinding for 15 times by using a three-roll grinder until the mixture is completely uniform to obtain a mixture III;
5. and adding the aqueous polyurethane emulsion into the third mixture, manually stirring for 45 seconds, and grinding for 5 times by using a three-roll grinder until the mixture is completely uniform to obtain a finished paste body of the Cu-Sn-Ti solder powder.
Example 4
The paste forming body for the Cu-Sn-Ti solder powder comprises the following components in percentage by weight:
poly (2-ethyl-2-oxazoline): 22.5 percent
Polypropylene carbonate: 3 percent of
Soluble starch: 7 percent of
Aqueous polyurethane emulsion: 50 percent of
Pentaerythritol: 0.5 percent
Glycerol: 7 percent of
Deionized water: 10 percent.
The mass average molecular weight of the poly (2-ethyl-2-oxazoline) is 200000, and the mass average molecular weight of the polypropylene carbonate is 500000; the polyurethane emulsion is Dispercoll U54 type aqueous polyurethane emulsion with the solid content of 50 percent.
The preparation method of the paste-forming body comprises the following steps:
3. weighing the components according to the weight percentage;
2. adding poly (2-ethyl-2-oxazoline), polypropylene carbonate and glycerol into a high-speed mixer (600 revolutions per minute), mixing for 2 hours, stopping mixing, cooling to room temperature, and taking out the mixture to obtain a mixture I;
3. adding soluble starch and pentaerythritol into deionized water, heating to 100 ℃ while stirring, and continuously stirring until the mixture is completely uniform to obtain a mixture II;
4. adding the mixture I into the mixture II, manually stirring for 45 seconds, and grinding for 15 times by using a three-roll grinder until the mixture is completely uniform to obtain a mixture III;
5. and adding the aqueous polyurethane emulsion into the third mixture, manually stirring for 45 seconds, and grinding for 5 times by using a three-roll grinder until the mixture is completely uniform to obtain a finished paste body of the Cu-Sn-Ti solder powder.
Example 5
The paste forming body for the Cu-Sn-Ti solder powder comprises the following components in percentage by weight:
poly (2-ethyl-2-oxazoline): 15 percent of
Polypropylene carbonate: 0.5 percent
Soluble starch: 5.5 percent
Aqueous polyurethane emulsion: 30 percent of
Pentaerythritol: 1 percent of
Glycerol: 8 percent of
Deionized water: 40 percent.
The mass average molecular weight of the poly (2-ethyl-2-oxazoline) is 200000, and the mass average molecular weight of the polypropylene carbonate is 500000; the aqueous polyurethane emulsion is Dispercoll U54 type aqueous polyurethane emulsion of Corsia, and the solid content is 50%.
The preparation method of the paste-forming body comprises the following steps:
6. weighing the components according to the weight percentage;
7. adding poly (2-ethyl-2-oxazoline), polypropylene carbonate and glycerol into a high-speed mixer (300 revolutions per minute), mixing for 2 hours, stopping mixing, cooling to room temperature, and taking out the mixture to obtain a mixture I;
8. adding soluble starch and pentaerythritol into deionized water, heating to 100 ℃ while stirring, and continuously stirring until the mixture is completely uniform to obtain a mixture II;
9. adding the mixture I into the mixture II, manually stirring for 30 seconds, and grinding for 10 times by using a three-roll grinder until the mixture is completely uniform to obtain a mixture III;
and adding the aqueous polyurethane emulsion into the third mixture, manually stirring for 30 seconds, and grinding for 3 times by using a three-roll grinder until the mixture is completely uniform to obtain a finished paste body of the Cu-Sn-Ti solder powder.
Verification of the effects of the invention
1. The paste obtained in example 1 was mixed with Cu-25Sn-10Ti solder powder at a ratio of 15:85, and the mixture was used for soldering of cBN particles in an amount required for the conventional operation of soldering of cBN particles, to obtain sample 1.
2. The same Cu-25Sn-10Ti solder powder was used alone in the cBN particle brazing operation without adding the paste forming body of the present invention, and the obtained sample was sample 2.
3. The cBN particle brazing product obtained by the two operation modes is taken and subjected to a sand blasting test, and the sand blasting air flow is stabilized at 5 multiplied by 105Pa, the incident angle is 90 degrees; alumina powder with the particle size of 400-600 microns is used as sand blasting particles, the distance between a nozzle and a brazing surface is kept at 110mm, and the area of a test surface is 113mm2The test results are shown in the table below, which shows the mass loss of the test specimens after 180s blasting.
| Sample (I) | Abrasion loss mu g/mm2 |
| Sample 1 | 103 |
| Sample 2 | 200 |
As can be seen from the above table, the paste-formed body prepared by the invention is added with Cu-Sn-Ti brazing filler metal powder and then used for the brazing operation of cBN particles, so that the wear resistance of the brazing filler metal layer can be greatly improved, and the technical effect is very obvious compared with the product without the paste-formed body.
The foregoing description of specific embodiments of the present invention has been presented. It is to be understood that the present invention is not limited to the specific embodiments described above, and that various changes and modifications may be made by one skilled in the art within the scope of the appended claims without departing from the spirit of the invention.