CN111809093A - Wear-resistant hard alloy and preparation method thereof - Google Patents
Wear-resistant hard alloy and preparation method thereof Download PDFInfo
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- CN111809093A CN111809093A CN202010702120.1A CN202010702120A CN111809093A CN 111809093 A CN111809093 A CN 111809093A CN 202010702120 A CN202010702120 A CN 202010702120A CN 111809093 A CN111809093 A CN 111809093A
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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
- C22C1/053—Making hard metals based on borides, carbides, nitrides, oxides or silicides; Preparation of the powder mixture used as the starting material therefor with in situ formation of hard compounds
- C22C1/056—Making hard metals based on borides, carbides, nitrides, oxides or silicides; Preparation of the powder mixture used as the starting material therefor with in situ formation of hard compounds using gas
-
- 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
Abstract
The invention discloses a wear-resistant hard alloy and a preparation method thereof, wherein the wear-resistant hard alloy comprises the following raw materials in parts by weight: 85-91 parts of tungsten carbide WC powder, 8-13 parts of cobalt powder Co, 0.5-1.5 parts of vinylene carbonate VC, and chromium carbide Cr3C20.6-1.2 parts of powder, 0.5-0.9 part of carbonyl Ni and 30-40 parts of titanium Ti powder, and tungsten carbide (WC) powder, cobalt powder, Vinylene Carbonate (VC) and chromium carbide (Cr) are mixed according to a set proportion3C2Adding the powder, carbonyl Ni powder and Ti powder into ball milling equipment, and drying and spraying the powder to prepare powder particles after ball milling to obtain mixed powder; carrying out hydrogen reduction on the mixed powder in reduction equipment, and cooling and taking out the reduced material; pressing and forming to obtain a semi-finished product; sintering the semi-finished product, performing high-temperature pressure sintering under the inert atmosphere condition, and cooling to obtain the wear-resistant hard alloy material. The invention has higher wear resistance and improves the quality of the material.
Description
Technical Field
The invention belongs to the technical field of hard alloy, and particularly relates to wear-resistant hard alloy and a preparation method thereof.
Background
Cemented carbide is an alloy material made from a hard compound of refractory metals and a binder metal by a powder metallurgy process. Cemented carbide as a kind of special tool material has been widely used in the manufacture of cutting tools, cutters, cobalt tools and wear-resistant parts, and is widely used in the fields of military industry, aerospace, machining, metallurgy, oil drilling, mining tools, electronic communication, construction and the like.
Chinese patent application No. 201510541956.7 discloses a cemented carbide material, which is composed of the following components by weight percent: 1-20% of a binding phase and 80-99% of a hard phase, wherein the hard phase consists of WC and TiAlCN, the WC accounts for 60-98.5% of the weight of the hard alloy material, and the TiAlCN accounts for 0.5-20% of the weight of the hard alloy material. The hard alloy provided by the prior art can enable the hard phase to have higher hardness and oxidation resistance, can improve the high-temperature strength, hardness and toughness of the prepared hard alloy tool, and the TiAlCN hard phase can also refine WC hard phase grains and improve the hardness, strength and toughness of the hard alloy; the TiAlCN hard phase can form a compact oxide protective film on the surface of a tool in the high-temperature use process of hard alloy, the oxidation resistance temperature reaches over 800 ℃, the hard alloy tool is resistant to vulcanization and corrosion of various media, and the hard alloy tool can work in high-temperature and severe environments. The strength, hardness and wear resistance of such cemented carbides still remain to be improved.
Disclosure of Invention
In order to solve the technical problems, the invention provides a wear-resistant hard alloy and a preparation method thereof.
In order to solve the technical problems, the invention adopts the following technical scheme:
the wear-resistant hard alloy comprises the following raw materials in parts by weight:
85-91 parts of tungsten carbide WC powder8-13 parts of cobalt powder Co, 0.5-1.5 parts of vinylene carbonate VC, and chromium carbide Cr3C20.6-1.2 parts of powder, 0.5-0.9 part of carbonyl Ni and 30-40 parts of titanium Ti powder.
The tungsten carbide WC powder is ultra-fine grain WC powder with the HCP value of (38.5-40.5) KA/m.
The average grain diameter of the tungsten carbide WC powder is 0.8-0.85 mu m.
The alloy comprises the following raw materials in parts by weight:
88 parts of tungsten carbide WC powder, 10 parts of cobalt powder Co, 1 part of vinylene carbonate VC, and Cr carbide3C21 part of powder, 0.7 part of carbonyl Ni and 35 parts of titanium Ti powder.
A preparation method of wear-resistant hard alloy comprises the following steps:
according to the set proportion, tungsten carbide WC powder, cobalt powder, vinylene carbonate VC and chromium carbide Cr3C2Adding the powder, carbonyl Ni powder and Ti powder into ball milling equipment, and drying and spraying the powder to prepare powder particles after ball milling to obtain mixed powder;
carrying out hydrogen reduction on the mixed powder in reduction equipment, and cooling and taking out the reduced material;
pressing and forming to obtain a semi-finished product;
sintering the semi-finished product, performing high-temperature pressure sintering under the inert atmosphere condition, and cooling to obtain the wear-resistant hard alloy material.
In the sintering process, the temperature is increased from room temperature to 800-1000 ℃ at the temperature increase speed of 5-7 ℃/min, the constant temperature is kept for 60-80 min, then the temperature is increased from 800-1000 ℃ to 1300-1350 ℃ at the temperature increase speed of 8-10 ℃/min, and the constant temperature is kept for 30-45 min.
In the cooling process after sintering, under the condition of inert argon atmosphere and pressure of 5-8 MPa, firstly, the temperature is reduced from 1300-1350 ℃ to 500-600 ℃ at the temperature reduction rate of 14-25 ℃/min, the temperature is kept for 1-2 h at constant temperature, and then, under the inert argon atmosphere, the material is naturally cooled to room temperature under the normal pressure condition.
The hard alloy prepared by the invention has the advantages of higher hardness, good wear resistance and long service life.
Detailed Description
The present invention will be described in further detail with reference to specific embodiments in order to further understand the features and technical means of the invention and achieve specific objects and functions.
Example one
The preparation method of the wear-resistant hard alloy is characterized by comprising the following steps:
according to the set proportion, 85 parts of tungsten carbide WC powder, 8 parts of cobalt powder Co, 0.5 part of vinylene carbonate VC and chromium carbide Cr3C20.6 part of powder, 0.5 part of carbonyl Ni and 30 parts of titanium Ti powder are added into ball milling equipment, and the mixture is dried and sprayed to prepare powder particles after ball milling to obtain mixed powder.
And (3) carrying out hydrogen reduction on the mixed powder in reduction equipment, and cooling and taking out the reduced material.
And pressing and forming to obtain a semi-finished product.
Sintering the semi-finished product, performing high-temperature pressure sintering under the inert atmosphere condition, and cooling to obtain the wear-resistant hard alloy material.
In the sintering process, the temperature is increased from room temperature to 800 ℃ at the temperature increase speed of 5 ℃/min, the constant temperature is kept for 60min, then the temperature is increased from 800 ℃ to 1300 ℃ at the temperature increase speed of 8 ℃/min, and the constant temperature is kept for 30 min.
In the cooling process after sintering, under the condition of inert argon atmosphere and pressure of 5MPa, the temperature is firstly reduced from 1300 ℃ to 500 ℃ at the temperature reduction rate of 14 ℃/min, the temperature is kept for 1h at constant temperature, and then the sintered product is naturally cooled to the room temperature under the condition of inert argon atmosphere and normal pressure.
Example two
The preparation method of the wear-resistant hard alloy is characterized by comprising the following steps:
according to the set proportion, 88 parts of tungsten carbide WC powder, 10 parts of cobalt powder Co, 1 part of vinylene carbonate VC, and chromium carbide Cr3C2Adding 1 part of powder, 0.7 part of carbonyl Ni and 35 parts of titanium Ti powder into ball milling equipment, and drying and spraying the powder after ball milling to prepare powder particles so as to obtain mixed powder.
And (3) carrying out hydrogen reduction on the mixed powder in reduction equipment, and cooling and taking out the reduced material.
And pressing and forming to obtain a semi-finished product.
Sintering the semi-finished product, performing high-temperature pressure sintering under the inert atmosphere condition, and cooling to obtain the wear-resistant hard alloy material.
In the sintering process, the temperature is increased from room temperature to 900 ℃ at the heating rate of 6 ℃/min, the constant temperature is kept for 70min, then the temperature is increased from 900 ℃ to 1320 ℃ at the heating rate of 9 ℃/min, and the constant temperature is kept for 40 min.
In the cooling process after sintering, under the condition of inert argon atmosphere and 6MPa pressure, the temperature is firstly reduced from 1320 ℃ to 550 ℃ at the cooling rate of 20 ℃/min, the temperature is kept for 1.5h at constant temperature, and then the sintered product is naturally cooled to the room temperature under the condition of inert argon atmosphere and normal pressure.
EXAMPLE III
A preparation method of wear-resistant hard alloy comprises the following steps:
according to the set proportion, 91 parts of tungsten carbide WC powder, 13 parts of cobalt powder Co, 1.5 parts of vinylene carbonate VC, and chromium carbide Cr3C21.2 parts of powder, 0.9 part of carbonyl Ni0.9 part of titanium Ti powder and 40 parts of titanium Ti powder are added into ball milling equipment, and the mixture is subjected to ball milling, drying and spray powder preparation to obtain mixed powder.
And (3) carrying out hydrogen reduction on the mixed powder in reduction equipment, and cooling and taking out the reduced material.
And pressing and forming to obtain a semi-finished product.
Sintering the semi-finished product, performing high-temperature pressure sintering under the inert atmosphere condition, and cooling to obtain the wear-resistant hard alloy material.
In the sintering process, the temperature is increased from room temperature to 1000 ℃ at the heating rate of 7 ℃/min, the constant temperature is kept for 80min, then the temperature is increased from 1000 ℃ to 1350 ℃ at the heating rate of 10 ℃/min, and the constant temperature is kept for 45 min.
In the cooling process after sintering, under the condition of inert argon atmosphere and pressure of 8MPa, firstly, the temperature is reduced from 1350 ℃ to 600 ℃ at the cooling rate of 25 ℃/min, the temperature is kept for 2 hours at constant temperature, and then, the sintered product is naturally cooled to the room temperature under the condition of inert argon atmosphere and normal pressure.
Although the present invention has been described in detail with reference to the embodiments, it will be apparent to those skilled in the art that modifications, equivalents, improvements, and the like can be made in the technical solutions of the foregoing embodiments or in some of the technical features of the foregoing embodiments, but those modifications, equivalents, improvements, and the like are all within the spirit and principle of the present invention.
Claims (7)
1. The wear-resistant hard alloy is characterized by comprising the following raw materials in parts by weight:
85-91 parts of tungsten carbide WC powder, 8-13 parts of cobalt powder Co, 0.5-1.5 parts of vinylene carbonate VC, and chromium carbide Cr3C20.6-1.2 parts of powder, 0.5-0.9 part of carbonyl Ni and 30-40 parts of titanium Ti powder.
2. The wear-resistant cemented carbide according to claim 1, wherein the WC powder is ultra-fine grain WC powder with HCP value of (38.5-40.5) KA/m.
3. The wear-resistant cemented carbide according to claim 2, characterized in that the mean grain size of the tungsten carbide WC powder is 0.8-0.85 μm.
4. The wear resistant cemented carbide according to claim 3, characterized in that the alloy comprises the following raw materials in parts by weight:
88 parts of tungsten carbide WC powder, 10 parts of cobalt powder Co, 1 part of vinylene carbonate VC, and Cr carbide3C21 part of powder, 0.7 part of carbonyl Ni and 35 parts of titanium Ti powder.
5. A method for producing a wear resistant cemented carbide according to any of claims 1-4, characterized in that it comprises the steps of:
according to the set proportion, tungsten carbide WC powder, cobalt powder, vinylene carbonate VC and chromium carbide Cr3C2Adding the powder, carbonyl Ni powder and Ti powder into ball milling equipment, and drying and spraying the powder to prepare powder particles after ball milling to obtain mixed powder;
carrying out hydrogen reduction on the mixed powder in reduction equipment, and cooling and taking out the reduced material;
pressing and forming to obtain a semi-finished product;
sintering the semi-finished product, performing high-temperature pressure sintering under the inert atmosphere condition, and cooling to obtain the wear-resistant hard alloy material.
6. The method for preparing the wear-resistant hard alloy according to claim 5, wherein in the sintering process, the temperature is raised from room temperature to 800-1000 ℃ at a temperature raising speed of 5-7 ℃/min, the temperature is kept for 60-80 min at a constant temperature, then the temperature is raised from 800-1000 ℃ to 1300-1350 ℃ at a temperature raising speed of 8-10 ℃/min, and the temperature is kept for 30-45 min at a constant temperature.
7. The preparation method of the wear-resistant hard alloy according to claim 6, wherein in the cooling process after sintering, under the condition of an inert argon atmosphere and a pressure of 5-8 MPa, the temperature is firstly reduced from 1300-1350 ℃ to 500-600 ℃ at a cooling rate of 14-25 ℃/min, the temperature is kept at a constant temperature for 1-2 hours, and then the cooling process is naturally carried out to room temperature under the condition of normal pressure under the inert argon atmosphere.
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| CN202010702120.1A CN111809093A (en) | 2020-07-21 | 2020-07-21 | Wear-resistant hard alloy and preparation method thereof |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113234981A (en) * | 2021-05-20 | 2021-08-10 | 九江金鹭硬质合金有限公司 | High-temperature-resistant high-thermal-expansion-coefficient hard alloy |
| CN113322389A (en) * | 2021-06-01 | 2021-08-31 | 株洲硬质合金集团有限公司 | Sintering method of wear-resistant corrosion-resistant superfine hard alloy |
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| CN102296223A (en) * | 2011-08-15 | 2011-12-28 | 四川欧曼机械有限公司 | Fine grain WC-based cemented carbide material and its preparation method |
| CN105734318A (en) * | 2016-04-21 | 2016-07-06 | 长沙微纳坤宸新材料有限公司 | Method for preparing nano-gradient composite W-Cu material |
| CN105950935A (en) * | 2016-05-05 | 2016-09-21 | 苏州新锐合金工具股份有限公司 | Hard alloy mold material for fastener formed through cold upsetting and preparation method of hard alloy mold material |
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| CN109457162A (en) * | 2018-12-29 | 2019-03-12 | 重庆文理学院 | Superhard metallic composite of a kind of Ti (C, N) base and preparation method thereof |
| CN109763053A (en) * | 2019-03-05 | 2019-05-17 | 常熟中材钨业科技有限公司 | A kind of mold high temperature toughness cemented carbide material and preparation method thereof |
| CN111254337A (en) * | 2020-03-10 | 2020-06-09 | 株洲明日硬质合金有限公司 | Hard alloy anti-skid nail core for automobile tire and preparation method thereof |
| CN111378860A (en) * | 2018-12-28 | 2020-07-07 | 自贡硬质合金有限责任公司 | Ultra-fine grain hard alloy and preparation method thereof |
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2020
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| JPH0533098A (en) * | 1991-07-29 | 1993-02-09 | Mitsubishi Materials Corp | Cemented carbide |
| CN102069093A (en) * | 2009-11-20 | 2011-05-25 | 鞍钢股份有限公司 | Tungsten carbide roller |
| CN101994051A (en) * | 2010-10-14 | 2011-03-30 | 浙江恒成硬质合金有限公司 | Tungsten carbide roll collar formula |
| CN102296223A (en) * | 2011-08-15 | 2011-12-28 | 四川欧曼机械有限公司 | Fine grain WC-based cemented carbide material and its preparation method |
| EP2906515B1 (en) * | 2012-10-09 | 2018-12-19 | Sandvik Hyperion AB | Low binder, wear resistant hard material |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113234981A (en) * | 2021-05-20 | 2021-08-10 | 九江金鹭硬质合金有限公司 | High-temperature-resistant high-thermal-expansion-coefficient hard alloy |
| CN113322389A (en) * | 2021-06-01 | 2021-08-31 | 株洲硬质合金集团有限公司 | Sintering method of wear-resistant corrosion-resistant superfine hard alloy |
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Application publication date: 20201023 |