A heat treatment process for soft magnetic alloy 1J50 material parts

Abstract

The application belongs to the technical field of heat treatment, and discloses a heat treatment process method of a soft magnetic alloy 1J50 material part. The soft magnetic alloy 1J50 material part is heated to 400 DEG C with a furnace, in the heating stage of 400 DEG C-800 DEG C, the heating speed is controlled to be less than or equal to 120 DEG C / h, in the heating stage of 800 DEG C-1200 DEG C, the heating speed is controlled to be less than or equal to 80 DEG C / h, the temperature is kept at 1190 DEG C±10 DEG C for 6 hours, then the cooling speed is 15 DEG C per 15 minutes, the temperature is cooled to 400 DEG C, and then the cooling speed is greater than 400 DEG C / h, the temperature is cooled to 150 DEG C, and the furnace is discharged for air cooling.

Description

Technical Field

[0001] This invention belongs to the field of heat treatment technology, and in particular relates to a heat treatment process for soft magnetic alloy 1J50 material parts. Background Technology

[0002] The stator and rotor laminations are made of 1J50, a soft magnetic alloy with high permeability and high saturation magnetic induction. Some of their magnetic properties are achieved through a rigorous heat treatment process. The quality after heat treatment cannot be directly inspected on the parts; it is determined whether the design requirements are met by testing the magnetic properties of the specimens. Therefore, the performance of the parts is closely related to the control of the heat treatment process.

[0003] A stator lamination using this soft magnetic alloy material underwent several trial productions, but the magnetic properties of the heat-treated specimens consistently failed the tests, impacting product performance and delivery. During the trial production phase of the product parts, heat treatment process experiments were conducted to determine the magnetic annealing temperature, holding time, heating rate, and cooling rate. Controlling the entire heat treatment process ensured the magnetic requirements of the product parts were met. This laid the foundation for subsequent new product trials and the application of new materials. Summary of the Invention

[0004] This invention provides a heat treatment process for 1J50 soft magnetic alloy parts, solving the problem that the magnetic properties of 1J50 parts fail the test after heat treatment, affecting product performance and delivery. Soft magnetic alloys require high magnetic flux density, low coercivity, and high permeability. Some also require certain physical properties such as constant permeability, moment ratio, low iron loss, and wear resistance. These properties can only be achieved through different heat treatment processes, making heat treatment a crucial step in the manufacturing process for soft magnetic alloys.

[0005] The technical solution of the present invention: a heat treatment process for soft magnetic alloy 1J50 material parts, the method comprising: The soft magnetic alloy 1J50 material parts are heated to 400℃ in the furnace. During the heating stage from 400℃ to 800℃, the heating rate is controlled within 120℃ / h. During the heating stage from 800℃ to 1200℃, the heating rate is controlled within 80℃ / h. Hold at 1190±10℃ for 6 hours, then cool to 400℃ at a rate of 15℃ every 15 minutes, and then cool to 150℃ at a rate greater than 400℃ / h before air cooling.

[0006] Furthermore, the magnetic properties of the parts after heat treatment were tested as follows: maximum permeability μm≥90.6mH / m, coercivity Hc≤4.611C / m, permeability μ0.4≥7.61mH / m in a magnetic field of 0.4A / m, and saturation magnetic induction Bs≥1.54T.

[0007] Furthermore, a hydrogen furnace is used to purify dry hydrogen, producing high-purity hydrogen with a dew point ≤ -40℃, which is used to remove harmful impurities C, N, O, and S from the alloy surface. At high temperatures, hydrogen reduces non-metallic oxides and nitrides, eliminating O, N, and S from the compounds.

[0008] Furthermore, the method also includes: Clean the grease, moisture or other dirt from the surface of the parts and test pieces, and blow dry or air dry them after cleaning; arrange the parts neatly and string them on the mandrel; load them into the furnace.

[0009] Furthermore, before loading the parts into the furnace, alumina powder or magnesium oxide powder is sprinkled on them. The alumina powder or magnesium oxide powder used is kept dry after being roasted at high temperature.

[0010] Furthermore, the thickness of the alumina powder or magnesium oxide powder is 0.1 mm.

[0011] Furthermore, the thickness of the soft magnetic alloy 1J50 material part is 0.2mm.

[0012] The heat treatment process for 1J50 material parts provided by this invention has been applied to aerospace motor products, solving the problem of insufficient magnetic properties and promoting normal operation of the products. Attached Figure Description

[0013] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. The drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0014] Figure 1 This is a schematic diagram of the heat treatment process for 1J50 material parts provided by the present invention. Detailed Implementation

[0015] The present invention will be further described in detail below with reference to the embodiments and accompanying drawings, but the embodiments of the present invention are not limited thereto.

[0016] Soft magnetic alloys require high purity of raw materials. Most of them are made from industrially pure raw materials that are vacuum smelted or electroslag remelted, forged and rolled, and finally shipped in a cold-deformed state. If the manufacturer ships them in a heat-treated (magnetic annealed) state, the material will have low hardness, be easily scratched and deformed, and its magnetic properties will be greatly reduced under slight stress. Therefore, it must be processed into parts or components, such as stator laminations, rotor laminations, and armature assemblies, by the production department, and then undergo final heat treatment (magnetic annealing) to meet the performance requirements.

[0017] Unlike structural materials, soft magnetic alloys require high magnetic flux density, low coercivity, and high permeability. Some also require certain physical properties, such as constant permeability, moment ratio, low iron loss, and wear resistance. These properties can only be achieved through different heat treatment processes. Therefore, heat treatment of soft magnetic alloys has become an important part of the manufacturing process.

[0018] According to design requirements, the stator and rotor laminations, made of 1J50 material, should meet the following magnetic properties after heat treatment: μm≥50mH / m (maximum permeability), Hc≤11.2A / m (coercivity), μ0.4≥3.3mH / m (permeability in a magnetic field of 0.4A / m), Bs≥1.5T (saturation magnetic induction). Heat treatment process for 1J50 material: Because the parts are relatively thin (0.2mm), they are prone to thermal and structural stress. Therefore, during the heating process, temperature control was implemented not only at both the high-temperature and low-temperature stages to reduce the thermal stress generated during heating. During the cooling process, the temperature was lowered slowly, then rapidly cooled to 400℃. This not only completed the structural transformation but also reduced the structural stress generated during the transformation process, resulting in a significant improvement in magnetic properties.

[0019] The heat treatment method for 1J50 material addresses the issue of insufficient magnetic properties in 1J50 material specimens by developing the following process: cleaning → placement → preventing adhesion → loading into the furnace (equipment selection) → magnetic annealing.

[0020] Cleaning: Remove grease, moisture, or other contaminants from the surface of parts and test pieces, and then blow dry or air dry them.

[0021] Placement: The parts are neatly arranged and strung on the mandrel.

[0022] To prevent adhesion: In order to prevent parts and specimens from sticking together at high temperatures, in addition to carefully removing burrs, alumina powder (magnesium oxide powder can also be used) should be sprinkled on the parts and specimens before loading them into the furnace. The alumina powder used should be dried by high-temperature baking.

[0023] Furnace loading: Before loading the furnace, place the specimen flat in the box, stack the sheets neatly, and there should be an alumina powder layer of about 0.1 mm between the sheets. Place the specimen in a representative position in the middle of the part.

[0024] Equipment: Hydrogen furnace, purified dry hydrogen, high-purity hydrogen, dew point ≤ -40℃, effectively removes harmful impurities C, N, O, and S from the alloy surface. At high temperatures, hydrogen reduces non-metallic oxides and nitrides, eliminating O, N, and S from compounds, and has a good effect on reducing oxidation and rust on alloy surfaces.

[0025] After multiple process experiments, the optimal heat treatment process was determined, with reference to... Figure 1 : First, the temperature rise must be controlled. The furnace temperature is raised to 400℃. During the 400℃-800℃ rising stage, the temperature is controlled within 120℃ / h. During the 800℃-1200℃ rising stage, the temperature is controlled within 80℃ / h.

[0026] Magnetic annealing: In a hydrogen furnace at 1190±10℃, hold for 6 hours, then cool to 400℃ at a rate of 15℃ every 15 minutes, and finally cool to 150℃ at a rate greater than 400℃ / h before air cooling. A schematic diagram of the process is shown below. Figure 1 .

[0027] The magnetic properties after magnetic annealing are as follows: μm≥90.6mH / m, Hc≤4.611C / m, μ0.4≥7.61mH / m, Bs≥1.54T. The magnetic properties after heat treatment meet the design requirements.

[0028] The above detailed embodiments are a description of the present invention. It should not be considered that the specific embodiments of the present invention are limited to these descriptions. For those skilled in the art, several simple deductions and substitutions can be made without departing from the concept of the present invention, and all of these should be considered to fall within the protection scope of the present invention.

Claims

1. A heat treatment process for parts made of soft magnetic alloy 1J50, characterized in that, The method includes: The soft magnetic alloy 1J50 material parts are heated to 400℃ in the furnace. During the heating stage from 400℃ to 800℃, the heating rate is controlled within 120℃ / h. During the heating stage from 800℃ to 1200℃, the heating rate is controlled within 80℃ / h. Hold at 1190±10℃ for 6 hours, then cool to 400℃ at a rate of 15℃ every 15 minutes, and then cool to 150℃ at a rate greater than 400℃ / h before air cooling.

2. The heat treatment process for soft magnetic alloy 1J50 material parts according to claim 1, characterized in that, The magnetic properties of the parts after heat treatment are as follows: maximum permeability μm≥90.6mH / m, coercivity Hc≤4.611C / m, permeability μ0.4≥7.61mH / m in a magnetic field of 0.4A / m, and saturation magnetic induction Bs≥1.54T.

3. The heat treatment process for soft magnetic alloy 1J50 material parts according to claim 1, characterized in that, A hydrogen furnace is used to purify dry hydrogen, producing high-purity hydrogen with a dew point ≤ -40℃. This is used to remove harmful impurities C, N, O, and S from the surface of alloys. At high temperatures, hydrogen reduces non-metallic oxides and nitrides, eliminating O, N, and S from the compounds.

4. The heat treatment process for soft magnetic alloy 1J50 material parts according to claim 1, characterized in that, The method further includes: Clean the grease, moisture or other dirt from the surface of the parts and test pieces, and blow dry or air dry them after cleaning; arrange the parts neatly and string them on the mandrel; load them into the furnace.

5. The heat treatment process for soft magnetic alloy 1J50 material parts according to claim 4, characterized in that, Before loading the furnace, alumina powder or magnesium oxide powder is sprinkled on the parts. The alumina powder or magnesium oxide powder used is kept dry after being baked at high temperature.

6. The heat treatment process for soft magnetic alloy 1J50 material parts according to claim 5, characterized in that, The thickness of the alumina powder or magnesium oxide powder is 0.1 mm.

7. The heat treatment process for soft magnetic alloy 1J50 material parts according to claim 5, characterized in that, The thickness of the soft magnetic alloy 1J50 material part is 0.2mm.

8. A part made of soft magnetic alloy 1J50 material, characterized in that, The part is processed using the heat treatment process method as described in any one of claims 1-7.

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