CN110791692A - Preparation method of hard alloy - Google Patents
Preparation method of hard alloy Download PDFInfo
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- CN110791692A CN110791692A CN201911005949.XA CN201911005949A CN110791692A CN 110791692 A CN110791692 A CN 110791692A CN 201911005949 A CN201911005949 A CN 201911005949A CN 110791692 A CN110791692 A CN 110791692A
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C29/00—Alloys based on carbides, oxides, nitrides, borides, or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides, sulfides
- C22C29/02—Alloys based on carbides, oxides, nitrides, borides, or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides, sulfides based on carbides or carbonitrides
- C22C29/06—Alloys based on carbides, oxides, nitrides, borides, or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides, sulfides based on carbides or carbonitrides based on carbides, but not containing other metal compounds
- C22C29/08—Alloys based on carbides, oxides, nitrides, borides, or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides, sulfides based on carbides or carbonitrides based on carbides, but not containing other metal compounds based on tungsten carbide
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C1/00—Making non-ferrous alloys
- C22C1/04—Making non-ferrous alloys by powder metallurgy
- C22C1/05—Mixtures of metal powder with non-metallic powder
- C22C1/051—Making hard metals based on borides, carbides, nitrides, oxides or silicides; Preparation of the powder mixture used as the starting material therefor
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C29/00—Alloys based on carbides, oxides, nitrides, borides, or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides, sulfides
- C22C29/02—Alloys based on carbides, oxides, nitrides, borides, or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides, sulfides based on carbides or carbonitrides
- C22C29/06—Alloys based on carbides, oxides, nitrides, borides, or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides, sulfides based on carbides or carbonitrides based on carbides, but not containing other metal compounds
- C22C29/067—Alloys based on carbides, oxides, nitrides, borides, or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides, sulfides based on carbides or carbonitrides based on carbides, but not containing other metal compounds comprising a particular metallic binder
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- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Powder Metallurgy (AREA)
Abstract
The invention discloses a preparation method of hard alloy, which is implemented according to the following steps: step 1, weighing the following powder according to weight percentage: WC: 70-85% of Ni3Al：18‑30％，B：0.04‑0.07％，Cu：0.04‑0.07％，Cr3C2: 0.001-0.8%, the balance being impurities; step 2, mixing the powder weighed in the step 1, adding a bonding agent, performing ball milling, and preparing an alloy blank by using a die; step 3, placing the alloy blank prepared in the step 2 in a glue discharging furnace for heating, and gasifying and discharging the adhesive in the alloy blank; step 4, performing pressure sintering on the alloy blank subjected to glue removal in the step 3 under the protection of inert gas; and 5, cooling the alloy blank subjected to pressure sintering, cooling to room temperature, and discharging.
Description
Technical Field
The invention belongs to the technical field of alloy preparation, and relates to a preparation method of hard alloy.
Background
The hard alloy is an alloy material prepared from a hard compound of refractory metal and bonding metal through a powder metallurgy process, has a series of excellent properties such as high hardness, wear resistance, good strength and toughness, heat resistance, corrosion resistance and the like, and is widely applied to the fields of cutter materials, machining, aerospace, high-pressure and high-temperature tests and the like.
With the emergence of more and more high hardness materials, the traditional hard alloy can not meet the cutting requirement of the cutter, the service life is seriously reduced, and then the machining cost is continuously increased, and the novel alloy cutter or the imported cutter is accompanied by higher machining cost. Therefore, the high-performance and low-cost domestic alloy cutter produced by the traditional hard alloy cutter manufacturing method can not only keep the excellent performance of the traditional hard alloy cutter, but also improve the wear resistance, the machining precision and the service life of the cutter on the basis of not reducing the impact toughness, and is an effective means for improving the competitiveness of the domestic alloy cutter.
Disclosure of Invention
The invention aims to provide a preparation method of hard alloy, which solves the problem that the production cost of the hard alloy with high toughness and strong wear resistance is high in the prior art.
The technical scheme adopted by the invention is that the preparation method of the hard alloy is implemented according to the following steps:
step 1, weighing the following powder according to weight percentage: WC: 70-85% of Ni3Al：18-30％，B：0.04-0.07％，Cu：0.04-0.07％，Cr3C2: 0.001-0.8%, and the balance of impurities.
Step 2, mixing the powder weighed in the step 1, adding a bonding agent, performing ball milling, and preparing an alloy blank by using a die;
step 3, placing the alloy blank prepared in the step 2 in a glue discharging furnace for heating, and gasifying and discharging the adhesive in the alloy blank;
step 4, performing pressure sintering on the alloy blank subjected to glue removal in the step 3 under the protection of inert gas;
and 5, cooling the alloy blank subjected to pressure sintering, cooling to room temperature, and discharging.
The invention is also characterized in that:
the powder weighed in step 1 is subjected to vacuum drying.
Step 2 the adhesive is paraffin, rubber or plastic.
The ball powder ratio of ball milling in the step 2 is 10: 1-200: 1, ball milling for 1-9h, drying after ball milling at 60-90 ℃ for 12-24 h.
And 3, heating the glue discharging furnace in a hydrogen combustion mode.
In the step 4, the temperature is raised at the speed of 50-300 ℃/min when sintering, the temperature is raised to 1400 ℃ and 1500 ℃, and the temperature is kept for 2.5-3.5 h.
And 5, cooling by adding liquid nitrogen or liquid argon into the furnace at a speed of 40-50 ℃/min.
The invention has the beneficial effects that:
the hard alloy prepared by the method is used for manufacturing a cutter, the cutter can cut high-hardness materials, is suitable for high-speed cutting, can prolong the service life of the cutter, and provides an optimal process for preparing the hard alloy;
the hard alloy prepared by the method has improved strength and hardness, and has excellent temperature resistance, wear resistance and impact toughness;
the method for preparing the hard alloy is simple and feasible, and can be conveniently used for mass production.
Detailed Description
The present invention will be described in detail with reference to the following embodiments.
The invention relates to a preparation method of hard alloy, which is implemented according to the following steps:
step 1, weighing the following powder according to weight percentage: WC: 70-85% of Ni3Al：18-30％，B：0.04-0.07％，Cu：0.04-0.07％，Cr3C2: 0.001-0.8% and the balance impurities, and vacuum drying the weighed powder.
And 2, mixing the powder subjected to vacuum drying in the step 1, adding paraffin, rubber or plastic, performing ball milling, and preparing an alloy blank by using a die, wherein the ball-milling ratio of ball powder is 10: 1-200: 1, ball milling for 1-9h, drying after ball milling, wherein the drying temperature is 60-90 ℃, and the drying time is 12-24 h;
step 3, placing the alloy blank prepared in the step 2 in a glue discharging furnace for heating, gasifying and discharging the adhesive in the alloy blank, and heating the glue discharging furnace in a hydrogen combustion mode;
step 4, performing pressure sintering on the alloy blank subjected to glue removal in the step 3 under the protection of inert gas, wherein the temperature is increased to 1400-1500 ℃ at the speed of 50-300 ℃/min during sintering, and the temperature is kept for 2.5-3.5 h;
and 5, cooling the alloy blank subjected to pressure sintering in a manner of adding liquid nitrogen or liquid argon into the furnace, wherein the cooling is carried out at the speed of 40-50 ℃/min, and discharging the alloy blank after the temperature is reduced to the room temperature.
Example 1
The invention relates to a preparation method of hard alloy, which is implemented according to the following steps:
step 1, weighing the following powder according to weight percentage: WC: 70% of Ni3Al：29％，B：0.07％，Cu：0.07％，Cr3C2: 0.8% and the balance impurities, the powder obtained was dried under vacuum.
And 2, mixing the powder subjected to vacuum drying in the step 1, adding paraffin, rubber or plastic, performing ball milling, and preparing an alloy blank by using a die, wherein the ball-milling ratio of ball powder is 10: 1, ball milling for 1h, drying after ball milling, wherein the drying temperature is 60 ℃, and the drying time is 12 h;
step 3, placing the alloy blank prepared in the step 2 in a glue discharging furnace for heating, gasifying and discharging the adhesive in the alloy blank, and heating the glue discharging furnace in a hydrogen combustion mode;
step 4, performing pressure sintering on the alloy blank subjected to glue discharge in the step 3 under the protection of inert gas, wherein the temperature is increased to 1400 ℃ at the speed of 50 ℃/min during sintering, and the temperature is kept for 2.5 hours;
and 5, cooling the alloy blank subjected to pressure sintering in a manner of adding liquid nitrogen or liquid argon into the furnace, wherein the cooling is carried out at the speed of 40 ℃/min, and the alloy blank is discharged after being cooled to the room temperature.
Example 2
The invention relates to a preparation method of hard alloy, which is implemented according to the following steps:
step 1, weighing the following powder according to weight percentage: WC: 75% of Ni3Al：24％，B：0.06％，Cu：0.06％，Cr3C2: 0.4% and the balance impurities, the powder obtained was dried under vacuum.
And 2, mixing the powder subjected to vacuum drying in the step 1, adding paraffin, rubber or plastic, performing ball milling, and preparing an alloy blank by using a die, wherein the ball-milling ratio of ball powder is 50: 1, ball milling for 3 hours, drying after ball milling, wherein the drying temperature is 70 ℃, and the drying time is 15 hours;
step 3, placing the alloy blank prepared in the step 2 in a glue discharging furnace for heating, gasifying and discharging the adhesive in the alloy blank, and heating the glue discharging furnace in a hydrogen combustion mode;
step 4, performing pressure sintering on the alloy blank subjected to glue discharge in the step 3 under the protection of inert gas, wherein the temperature is increased at the speed of 100 ℃/min, the temperature is increased to 1430 ℃, and the temperature is kept for 2.8 hours during sintering;
and 5, cooling the alloy blank subjected to pressure sintering in a manner of adding liquid nitrogen or liquid argon into the furnace, wherein the cooling is carried out at the speed of 42 ℃/min, and discharging the alloy blank after the temperature is reduced to the room temperature.
Example 3
The invention relates to a preparation method of hard alloy, which is implemented according to the following steps:
step 1, weighing the following powder according to weight percentage: WC: 80% of Ni3Al：19％，B：0.05％，Cu：0.05％，Cr3C2: 0.2% and the balance impurities, the powder obtained was dried under vacuum.
And 2, mixing the powder subjected to vacuum drying in the step 1, adding paraffin, rubber or plastic, performing ball milling, and preparing an alloy blank by using a die, wherein the ball-milling ball powder ratio is 100: 1, ball milling for 5 hours, drying after ball milling, wherein the drying temperature is 80 ℃, and the drying time is 18 hours;
step 3, placing the alloy blank prepared in the step 2 in a glue discharging furnace for heating, gasifying and discharging the adhesive in the alloy blank, and heating the glue discharging furnace in a hydrogen combustion mode;
step 4, performing pressure sintering on the alloy blank subjected to glue discharge in the step 3 under the protection of inert gas, heating up to 1450 ℃ at the speed of 200 ℃/min during sintering, and preserving heat for 3.0 h;
and 5, cooling the alloy blank subjected to pressure sintering in a manner of adding liquid nitrogen or liquid argon into the furnace, wherein the cooling is carried out at the speed of 45 ℃/min, and the alloy blank is discharged after being cooled to the room temperature.
Example 4
The invention relates to a preparation method of hard alloy, which is implemented according to the following steps:
step 1, weighing the following powder according to weight percentage: WC: 81% of Ni3Al：18％，B：0.05％，Cu：0.05％，Cr3C2: 0.1% and the balance impurities, the powder obtained was dried under vacuum.
And 2, mixing the powder subjected to vacuum drying in the step 1, adding paraffin, rubber or plastic, performing ball milling, and preparing an alloy blank by using a die, wherein the ball-milling ball powder ratio is 150: 1, ball milling for 7 hours, drying after ball milling, wherein the drying temperature is 85 ℃, and the drying time is 21 hours;
step 3, placing the alloy blank prepared in the step 2 in a glue discharging furnace for heating, gasifying and discharging the adhesive in the alloy blank, and heating the glue discharging furnace in a hydrogen combustion mode;
step 4, performing pressure sintering on the alloy blank subjected to glue discharge in the step 3 under the protection of inert gas, heating at the speed of 250 ℃/min to 1470 ℃ during sintering, and keeping the temperature for 3.0 h;
and 5, cooling the alloy blank subjected to pressure sintering in a mode of adding liquid nitrogen or liquid argon into the furnace, cooling at the speed of 47 ℃/min, and discharging the alloy blank after cooling to room temperature.
Example 5
The invention relates to a preparation method of hard alloy, which is implemented according to the following steps:
step 1, weighing the following powder according to weight percentage: WC: 81% of Ni3Al：18％，B：0.04％，Cu：0.04％，Cr3C2: 0.001% and the balance impurities, and vacuum drying the weighed powder.
And 2, mixing the powder subjected to vacuum drying in the step 1, adding paraffin, rubber or plastic, performing ball milling, and preparing an alloy blank by using a die, wherein the ball-milling ball powder ratio is 200: 1, ball milling for 9 hours, drying after ball milling, wherein the drying temperature is 90 ℃, and the drying time is 24 hours;
step 3, placing the alloy blank prepared in the step 2 in a glue discharging furnace for heating, gasifying and discharging the adhesive in the alloy blank, and heating the glue discharging furnace in a hydrogen combustion mode;
step 4, performing pressure sintering on the alloy blank subjected to glue discharge in the step 3 under the protection of inert gas, wherein during sintering, the temperature is increased at the speed of 300 ℃/min to 1500 ℃, and the temperature is kept for 3.5 hours;
and 5, cooling the alloy blank subjected to pressure sintering in a manner of adding liquid nitrogen or liquid argon into the furnace, wherein the cooling is carried out at the speed of 50 ℃/min, and the alloy blank is discharged after being cooled to room temperature.
The hardness and flexural strength of the cemented carbide obtained in examples 1 to 5 were measured together with conventional cemented carbide, and the results are shown in table 1.
TABLE 1
| Hardness (HRA) | Bending strength (N/mm 2) | |
| Example 1 | 93.8 | 3157 |
| Example 2 | 94.4 | 3068 |
| Example 3 | 95.1 | 2986 |
| Example 4 | 95.8 | 2889 |
| Example 5 | 96.4 | 2801 |
| Existing cemented carbide | 89.6 | 2579 |
The experimental result shows that the hard alloy prepared by the method has better strength and hardness, excellent wear resistance, impact toughness and other characteristics, and the manufactured cutter has longer service life. Meanwhile, the method for preparing the hard alloy has the advantages of simple process and lower cost, and is beneficial to wide application.
Claims (7)
1. The preparation method of the hard alloy is characterized by comprising the following steps:
step 1, weighing the following powder according to weight percentage: WC: 70-85% of Ni3Al：18-30％，B：0.04-0.07％，Cu：0.04-0.07％，Cr3C2: 0.001-0.8%, the balance being impurities;
step 2, mixing the powder weighed in the step 1, adding a bonding agent, performing ball milling, and preparing an alloy blank by using a die;
step 3, placing the alloy blank prepared in the step 2 in a glue discharging furnace for heating, and gasifying and discharging the adhesive in the alloy blank;
step 4, performing pressure sintering on the alloy blank subjected to glue removal in the step 3 under the protection of inert gas;
and 5, cooling the alloy blank subjected to pressure sintering, cooling to room temperature, and discharging.
2. The method according to claim 1, wherein the powder weighed in step 1 is subjected to vacuum drying.
3. The method for preparing a hard alloy according to claim 1, wherein the step 2 adhesive is paraffin wax, rubber or plastic.
4. The method for preparing hard alloy according to claim 1, wherein the ball-milling in the step 2 is performed at a ball-to-powder ratio of 10: 1-200: 1, ball milling for 1-9h, drying after ball milling at 60-90 ℃ for 12-24 h.
5. The method for preparing hard alloy according to claim 1, wherein the glue discharging furnace is heated in the glue discharging furnace in the step 3 by burning hydrogen.
6. The method as claimed in claim 1, wherein the temperature is raised at a rate of 50-300 ℃/min during the sintering in step 4 to 1400-1500 ℃, and the temperature is maintained for 2.5-3.5 h.
7. The method for preparing hard alloy according to claim 1, wherein the step 5 is performed by adding liquid nitrogen or liquid argon into the furnace, and the temperature is reduced at a speed of 40-50 ℃/min.
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| CN201911005949.XA CN110791692A (en) | 2019-10-22 | 2019-10-22 | Preparation method of hard alloy |
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| CN201911005949.XA CN110791692A (en) | 2019-10-22 | 2019-10-22 | Preparation method of hard alloy |
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Citations (7)
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| CN102560215A (en) * | 2012-02-17 | 2012-07-11 | 中南大学 | Ni3Al bonded ultra-fine grained tungsten carbide-based hard alloy and preparation method thereof |
| CN107190196A (en) * | 2017-06-09 | 2017-09-22 | 洛阳理工学院 | A kind of cutter high-wear-resistant alloy material and preparation method thereof |
| CN109652707A (en) * | 2017-10-12 | 2019-04-19 | 刘启乐 | One kind containing Ni3The WC-Co hard alloy of Al |
| CN110106424A (en) * | 2019-06-13 | 2019-08-09 | 河源市全诚硬质合金有限公司 | A kind of hard alloy bar and its manufacturing method |
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2019
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| CN107190196A (en) * | 2017-06-09 | 2017-09-22 | 洛阳理工学院 | A kind of cutter high-wear-resistant alloy material and preparation method thereof |
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Application publication date: 20200214 |