CN111471899A - High-performance soft magnetic alloy powder and preparation process for preparing complex parts - Google Patents
High-performance soft magnetic alloy powder and preparation process for preparing complex parts Download PDFInfo
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C19/00—Alloys based on nickel or cobalt
- C22C19/07—Alloys based on nickel or cobalt based on cobalt
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/10—Sintering only
- B22F3/1017—Multiple heating or additional steps
- B22F3/1021—Removal of binder or filler
- B22F3/1025—Removal of binder or filler not by heating only
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/22—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces for producing castings from a slip
- B22F3/225—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces for producing castings from a slip by injection molding
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- B—PERFORMING OPERATIONS; TRANSPORTING
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- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/24—After-treatment of workpieces or articles
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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
- C22C1/0433—Nickel- or cobalt-based alloys
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
- C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
- C22F1/02—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working in inert or controlled atmosphere or vacuum
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
- C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
- C22F1/10—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working of nickel or cobalt or alloys based thereon
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
- H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
- H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
- H01F1/12—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials
- H01F1/14—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials metals or alloys
- H01F1/147—Alloys characterised by their composition
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
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- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/24—After-treatment of workpieces or articles
- B22F2003/248—Thermal after-treatment
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Abstract
The invention relates to high-performance soft magnetic alloy powder and a preparation process for preparing a complex part, wherein the high-performance soft magnetic alloy powder comprises the following chemical components in percentage by mass: co: 50.1-55%, V: 0.1-3 wt%, C less than 0.01 wt%, Cr less than 0.1 wt%, Ni less than 0.1 wt%, Mn less than 0.1 wt%, Si less than 0.3 wt%, and the balance Fe. The preparation process mainly depends on a powder injection molding technology, the high-performance soft magnetic alloy powder and a binder are mixed to prepare a feed, and then a final product is obtained through degreasing sintering and annealing heat treatment. The invention can ensure the soft magnetic performance of the material and has higher mechanical property.
Description
Technical Field
The invention relates to high-performance soft magnetic alloy powder and a preparation process for preparing complex parts.
Background
The Fe-Co soft magnetic alloy has the characteristics of high saturation magnetic induction intensity, higher magnetic conductivity, low coercive force, low hysteresis loss, low resistivity and higher eddy current loss, and is suitable for being used under direct current and low frequency conditions. With the advent of the 5G era, various magnetic functional devices need to be added into more and more electronic devices, FeCo soft magnetic alloys have excellent mechanical properties and soft magnetic properties and great application potential, and how to select the components of the alloys and how to produce Fe-Co alloy parts with complex shapes and keep the balance of the mechanical properties and the soft magnetic properties becomes a problem to be solved urgently. Particularly, the mechanical property and the soft magnetic property of the existing MIM-FeCo50 sintered blank are low.
Disclosure of Invention
It is a first object of the present invention to provide a high-performance soft magnetic alloy powder capable of producing parts excellent in soft magnetic properties and mechanical properties.
The technical scheme for realizing the first purpose of the invention is as follows: the high-performance soft magnetic alloy powder comprises the following chemical components in percentage by mass: co: 50.1-55%, V: 0.1-3 wt%, C less than 0.01 wt%, Cr less than 0.1 wt%, Ni less than 0.1 wt%, Mn less than 0.1 wt%, Si less than 0.3 wt%, and the balance Fe.
As a specific design, the high-performance soft magnetic alloy powder comprises the following chemical components in percentage by mass: co: 51 wt%, V: 1.8 wt%, C less than 0.008 wt%, Cr less than 0.04 wt%, Ni less than 0.04 wt%, Mn less than 0.04 wt%, Si less than 0.23 wt%, and the balance Fe.
The high-performance magnetically soft alloy powder comprises the following chemical components in percentage by mass: co: 53.0 wt%, V: 1.4 wt%, C less than 0.008 wt%, Cr less than 0.04 wt%, Ni less than 0.04 wt%, Mn less than 0.04 wt%, Si less than 0.23 wt%, and the balance Fe.
The second purpose of the invention is to provide a preparation process for preparing complex parts based on the high-performance soft magnetic alloy powder.
The technical scheme for realizing the second purpose of the invention is as follows: the preparation process for preparing the complex part by using the high-performance soft magnetic alloy powder comprises the following steps:
s1, preparation of feed: mixing high-performance soft magnetic alloy powder with a binder to prepare a feed;
s2, injection molding: injecting and molding the feed material by an injection machine to form an injection blank;
s3, degreasing: degreasing the injection blank to form a degreased blank;
s4, sintering: and sintering the degreased blank to form a sintered blank.
S5, annealing heat treatment: and putting the sintered blank into a monomer furnace in a sintered state, and carrying out annealing heat treatment to finally form a final product.
The annealing atmosphere is argon, the atmosphere partial pressure is 5-30 kPa, the heat treatment process is 750-900 ℃, the temperature is kept for 3-8 h, and then the annealing atmosphere is slowly cooled to the room temperature at the cooling speed of 150-250 ℃/h.
V is precipitated at the crystal boundary in the form of oxide in the sintering process, the growth of crystal grains is inhibited, and fine grain strengthening and dispersion strengthening are formed, so that the strength and toughness of the material are improved, and the mechanical property is improved, but too much V can cause the crystal grains to be too small in size, hinder the sintering process and reduce the soft magnetic property, and meanwhile, the oxide of V can also lose the soft magnetic property of the material, so that the content of Co needs to be increased to reduce the addition of V, and the balance between the mechanical property and the soft magnetic property is achieved;
and annealing heat treatment is carried out on the sintered blank, the temperature is 750-900 ℃, the temperature is kept for 3-8 h, and then the sintered blank is slowly cooled to room temperature at the cooling speed of 150-250 ℃/h to release sintering internal stress, so that the plasticity is improved, the mechanical property is improved, crystal grains are grown up, and the soft magnetic property is improved.
The invention has the positive effects that: (1) the high-performance soft magnetic alloy provided by the invention has the advantages that the components are designed, and through analysis and optimization, the smooth sintering can be ensured in a certain range, the soft magnetic performance can be ensured, and particularly, the strength and toughness of the material can be ensured while the soft magnetic performance is ensured.
(2) The invention utilizes the metal powder injection molding (MIM) technology, so that the material utilization rate is high, the processing cost is saved, and the products with complicated geometric shapes can be prepared in a large scale.
Drawings
In order that the present disclosure may be more readily and clearly understood, reference is now made to the following detailed description of the present disclosure taken in conjunction with the accompanying drawings, in which
FIG. 1 is a diagram of a gold phase after sintering in example 1 of the present invention;
FIG. 2 is a metallographic image of a gold phase after heat treatment in example 1 of the present invention;
FIG. 3 is a hysteresis chart in embodiment 1 of the present invention;
FIG. 4 is a diagram of a gold phase after sintering in example 2 of the present invention;
FIG. 5 is a metallographic image of a gold phase after heat treatment in example 2 of the present invention;
fig. 6 is a hysteresis chart in embodiment 2 of the present invention.
Detailed Description
The traditional FeCo50 alloy is a soft magnetic alloy commonly used in MIM, but the soft magnetic property and the mechanical property are general, and the indexes are as follows:
(example 1)
In the embodiment, the high-performance soft magnetic alloy powder comprises the following chemical components in percentage by mass: co: 51 wt%, V: 1.8 wt%, C less than 0.008 wt%, Cr less than 0.04 wt%, Ni less than 0.04 wt%, Mn less than 0.04 wt%, Si less than 0.23 wt%, and the balance Fe.
The preparation process for preparing the complex part by using the high-performance soft magnetic alloy powder comprises the following steps:
s1, preparation of feed: mixing the high-performance soft magnetic alloy powder with a binder to prepare a feed; the main components of the binder are polypropylene, stearic acid, polyethylene wax and the like;
s2, injection molding: injecting and molding the feed material by an injection machine to form an injection blank;
s3, degreasing: degreasing the injection blank to form a degreased blank;
s4, sintering: and sintering the degreased blank to form a sintered blank.
S5, annealing heat treatment: and putting the sintered blank into a monomer furnace in a sintered state, and carrying out annealing heat treatment to finally form a final product.
Wherein, the degreasing is to carry out acid removal on the injection blank, and the acid introduction time is 300-400 min.
The sintering is carried out in a monomer furnace in a partial pressure sintering mode, the sintering atmosphere is Ar, the partial pressure is 8kPa, the sintering temperature is 1320 ℃, the heat preservation time is 6h, the furnace is cooled to 200 ℃, then Ar spraying fast cooling is carried out to obtain a sintered blank, the sintered blank in the sintering state is placed in the monomer furnace again to carry out annealing heat treatment, the sintering atmosphere is argon, the partial pressure is 15kPa, the heat treatment process is 800 ℃, the heat preservation time is 6h, and then the temperature is slowly cooled to the room temperature at the cooling speed of 220 ℃/h.
The performance parameters and C, O levels for the samples prepared according to this example were as follows:
the detailed experimental data are shown in fig. 1 to 3.
(example 2)
In the embodiment, the high-performance soft magnetic alloy powder comprises the following chemical components in percentage by mass: co: 53.0 wt%, V: 1.4 wt%, C less than 0.008 wt%, Cr less than 0.04 wt%, Ni less than 0.04 wt%, Mn less than 0.04 wt%, Si less than 0.23 wt%, and the balance Fe.
The preparation process for preparing the complex part by using the high-performance soft magnetic alloy powder comprises the following steps:
s1, preparation of feed: mixing the high-performance soft magnetic alloy powder with a binder to prepare a feed; the main components of the binder are polypropylene, stearic acid, polyethylene wax and the like;
s2, injection molding: injecting and molding the feed material by an injection machine to form an injection blank;
s3, degreasing: degreasing the injection blank to form a degreased blank;
s4, sintering: and sintering the degreased blank to form a sintered blank.
S5, annealing heat treatment: and putting the sintered blank into a monomer furnace in a sintered state, and carrying out annealing heat treatment to finally form a final product.
Wherein, the degreasing is to carry out acid removal on the injection blank, and the acid introduction time is 300-400 min.
The sintering is carried out in a monomer furnace in a partial pressure sintering mode, the sintering atmosphere is Ar, the partial pressure is 8kPa, the sintering temperature is 1340 ℃, the heat preservation time is 10 hours, the furnace is cooled to 200 ℃, then Ar spraying fast cooling is carried out to obtain a sintered blank, the sintered blank in the sintering state is placed in the monomer furnace again to carry out annealing heat treatment, the sintering atmosphere is argon, the partial pressure is 12kPa, the heat treatment process is 750 ℃, the heat preservation time is 8 hours, and then the temperature is slowly cooled to the room temperature at the cooling speed of 250 ℃/h.
The performance parameters and C, O levels for the samples prepared according to this example were as follows:
specific experimental data are shown in fig. 4 to 6.
The above-mentioned embodiments are intended to illustrate the objects, technical solutions and advantages of the present invention in further detail, and it should be understood that the above-mentioned embodiments are only exemplary embodiments of the present invention, and are not intended to limit the present invention, and any modifications, equivalents, improvements and the like made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (6)
1. The high-performance soft magnetic alloy powder is characterized in that: the composite material comprises the following chemical components in percentage by mass: co: 50.1-55%, V: 0.1-3 wt%, C less than 0.01 wt%, Cr less than 0.1 wt%, Ni less than 0.1 wt%, Mn less than 0.1 wt%, Si less than 0.3 wt%, and the balance Fe.
2. The high performance soft magnetic alloy powder according to claim 1, wherein: the composite material comprises the following chemical components in percentage by mass: co: 51 wt%, V: 1.8 wt%, C less than 0.008 wt%, Cr less than 0.04 wt%, Ni less than 0.04 wt%, Mn less than 0.04 wt%, Si less than 0.23 wt%, and the balance Fe.
3. The high performance soft magnetic alloy powder according to claim 1, wherein: the composite material comprises the following chemical components in percentage by mass: co: 53.0 wt%, V: 1.4 wt%, C less than 0.008 wt%, Cr less than 0.04 wt%, Ni less than 0.04 wt%, Mn less than 0.04 wt%, Si less than 0.23 wt%, and the balance Fe.
4. The process for preparing a complex part by using the high-performance soft magnetic alloy powder as claimed in claim 1, 2 or 3, which is characterized by comprising the following steps:
s1, preparation of feed: mixing high-performance soft magnetic alloy powder with a binder to prepare a feed;
s2, injection molding: injecting and molding the feed material by an injection machine to form an injection blank;
s3, degreasing: degreasing the injection blank to form a degreased blank;
s4, sintering: and sintering the degreased blank to form a sintered blank.
5. The process according to claim 4, characterized in that: further comprises S5 annealing heat treatment: and putting the sintered blank into a monomer furnace in a sintered state, and carrying out annealing heat treatment to finally form a final product.
6. The process according to claim 5, characterized in that: the annealing atmosphere is argon, the atmosphere partial pressure is 5-30 kPa, the heat treatment process is 750-900 ℃, the temperature is kept for 3-8 h, and then the annealing atmosphere is slowly cooled to the room temperature at the cooling speed of 150-250 ℃/h.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1592419A (en) * | 1978-04-17 | 1981-07-08 | Telcon Metals Ltd | Magnetic alloys |
| JPH03130322A (en) * | 1989-04-18 | 1991-06-04 | Nippon Steel Corp | Production of fe-co-type soft-magnetic material |
| CN104114724A (en) * | 2011-12-16 | 2014-10-22 | 艾普伦 | Process for manufacturing a thin strip made of soft magnetic alloy and strip obtained |
| CN110317976A (en) * | 2018-03-29 | 2019-10-11 | 精工爱普生株式会社 | The manufacturing method of soft magnetic powder and sintered body |
| CN110421175A (en) * | 2019-08-27 | 2019-11-08 | 江苏精研科技股份有限公司 | The method that ferrocobalt complex parts are prepared using powder injection forming |
-
2020
- 2020-04-27 CN CN202010343722.2A patent/CN111471899A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1592419A (en) * | 1978-04-17 | 1981-07-08 | Telcon Metals Ltd | Magnetic alloys |
| JPH03130322A (en) * | 1989-04-18 | 1991-06-04 | Nippon Steel Corp | Production of fe-co-type soft-magnetic material |
| CN104114724A (en) * | 2011-12-16 | 2014-10-22 | 艾普伦 | Process for manufacturing a thin strip made of soft magnetic alloy and strip obtained |
| CN110317976A (en) * | 2018-03-29 | 2019-10-11 | 精工爱普生株式会社 | The manufacturing method of soft magnetic powder and sintered body |
| CN110421175A (en) * | 2019-08-27 | 2019-11-08 | 江苏精研科技股份有限公司 | The method that ferrocobalt complex parts are prepared using powder injection forming |
Non-Patent Citations (4)
| Title |
|---|
| 何开元: "《高等学校教学用书 精密合金材料学》", 31 May 1991 * |
| 孙龙信: "《电机工程手册 第8篇 磁性材料》", 30 June 1982 * |
| 曹鹏军，等: "《金属材料学》", 30 November 2018 * |
| 马吕升: "《精密合金及粉末冶金材料》", 31 January 1982 * |
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