E-type iron core and preparation method thereof

Abstract

The present invention provides a method for preparing an E-type iron core, comprising the following steps: S1, designing an E-type iron core model; S2, 3D printing the E-type iron core: using 3D printing technology to print an integrally formed E-type iron core, wherein the E-type iron core comprises a plurality of E-type iron sheets and a spacer layer, the spacer layer is arranged between two adjacent E-type iron sheets, and the spacer layer is composed of a plurality of triangular support blocks; S3, hot isostatic pressing; S4, sandblasting and polishing; S5, coating with an insulating solution; S6, solidification and molding. The preparation method realizes the preparation of the E-type iron core by three-dimensional printing. The preparation method can not only realize one-to-one precise molding of various complex structures according to the three-dimensional design size of the E-type iron core, but also has low operating technical difficulty, fewer operating process steps, simpler equipment and low price. At the same time, the E-type iron core can be integrally formed, thereby avoiding the problem of brittle fracture of iron sheets prepared by conventional stamping methods.

Description

Technical Field

[0001] The invention relates to the technical field of E-type iron core processing, and in particular to a preparation method and manufacturing method of an E-type iron core. Background Art

[0002] With the continuous development of power electronics technology, motors play an increasingly important role in modern industry. The application range of motors spans from milliwatts to kilowatts to large megawatts, and they are widely used in professional fields such as family life, propulsion, and power generation. Almost all the electricity in the world is generated through the electromechanical conversion of motors. As the core component of the motor, the electromagnetic properties of the iron core have a significant impact on the performance of the motor.

[0003] At present, E-type iron core structures are mostly prepared by forging, casting, sintering, powder metallurgy and other methods. However, the iron core structures prepared by these methods often have the problem of limited geometric complexity. Due to the limited three-dimensional structure, it is often difficult to form iron core structures in various complex shapes. At the same time, due to limited processing accuracy, a large number of forming steps are often required to prepare thinner and lighter E-type iron core structures, which will lead to a longer processing cycle and higher preparation costs; especially when the material of the iron core sheet is a brittle material, the use of conventional stamping methods to prepare the iron core sheet is prone to brittle fracture, and it is impossible to form an E-type iron core with a complex structure in one go. Summary of the invention

[0004] In view of this, the purpose of the present invention is to avoid the shortcomings of the prior art and provide a method for preparing an E-type iron core. The preparation method realizes the preparation of the E-type iron core through three-dimensional printing. The preparation method can not only realize one-to-one precise forming of various complex structures according to the three-dimensional design dimensions of the E-type iron core, but also the preparation method has low operating technical difficulty, fewer operating process steps, simpler equipment and low price. At the same time, it can also realize the one-piece forming of the E-type iron core, avoiding the problem of brittle fracture of iron core sheets prepared by conventional stamping methods.

[0005] The present application provides a method for preparing an E-type iron core, comprising the following steps:

[0006] S1. Design of E-type core model: Use 3D drawing software to obtain the E-type core model;

[0007] S2. 3D printed E-shaped iron core: an E-shaped iron core is obtained by printing using 3D printing technology, wherein the E-shaped iron core comprises a plurality of E-shaped iron sheets and a spacer layer, the spacer layer is arranged between two adjacent E-shaped iron sheets, and the spacer layer is composed of a plurality of triangular support blocks;

[0008] S3, hot isostatic pressing: put the E-type iron core obtained by 3D printing into a hot isostatic pressing furnace, blow high-purity argon gas into the hot isostatic pressing furnace, and pressurize and keep warm under argon conditions;

[0009] S4, sandblasting and grinding: Use the sandblasting and grinding process to clean the sticky powder or impurities on the surface of the E-type iron core after hot isostatic pressing;

[0010] S5, coating the insulating solution: immersing the sandblasted and polished E-type iron core in the insulating solution, and coating the insulating solution on the surface of the E-type iron core by using an immersion and pulling method;

[0011] S6 curing molding: The insulating solution is cured on the surface of the E-type core by heat treatment.

[0012] Furthermore, in step S1, the three-dimensional drawing software is any one of Magics, Solidworks, UG, and VG.

[0013] Furthermore, in step S2, the 3D printing of the E-type core includes the following sub-steps:

[0014] S21, slicing the three-dimensional E-type core model in step S1 along the axial direction of the finger ring with a layer thickness of 30 to 50 μm, and generating a corresponding 3D model slice file;

[0015] S22, sending the 3D model slice file to the 3D printing system to wait for printing;

[0016] S23, taking FeSi or FeNi alloy powder, first sieving the alloy powder to obtain a powder with a particle size range of 30 to 45 μm, placing the powder in a vacuum drying oven for 4 hours, and finally pouring the dried powder into a 3D printing system to wait for printing; wherein the mass percentage of Si in the alloy powder FeSi is: 3% to 6.5%; the mass percentage of Ni in the alloy powder FeNi is: 45% to 55%;

[0017] S24, taking a stainless steel substrate, wiping its surface with alcohol, installing it in a 3D printing system, then closing the hatch of the 3D printing system, and introducing argon protective gas;

[0018] S25. Setting the printing parameters of the 3D printing system, and starting the 3D printing system to print an integrated E-shaped iron core; wherein the laser power is set to 70-90 W; the printed spot diameter is set to 30-40 μm, the scanning speed is set to 900-1100 mm / s, the powder thickness is set to 0.02-0.04 mm, and the scanning interval is set to 0.05-0.07 mm.

[0019] Furthermore, in step S2, the thickness of a single E-shaped iron sheet is 300-360 mm; the thickness of a single spacer layer is 60-90 mm;

[0020] The side length of the triangular support block is 60-90 mm, and the side length of the triangular support block is consistent with the thickness of the spacing layer; the longitudinal section of the triangular support block is arranged in an equilateral triangle.

[0021] Furthermore, the triangular support block is horizontally arranged between two adjacent E-shaped iron sheets, and a strip-shaped through hole is formed between a single E-shaped iron sheet and any two adjacent triangular support blocks.

[0022] Furthermore, the triangular support block is arranged at the edge contour of two adjacent E-shaped iron sheets, and forms an E-shaped sealed cavity between the triangular support block and the two adjacent E-shaped iron sheets.

[0023] Furthermore, in step S3, the hot isostatic pressing process is argon hot isostatic pressing; the process steps of the argon hot isostatic pressing are: first, the E-type iron core obtained by 3D printing is placed in a hot isostatic pressing furnace, and then high-purity argon is blown into the hot isostatic pressing furnace, and under argon conditions, the temperature is set to 850℃~900℃, the pressure is set to 100~110MPa, and after static pressing and heat preservation for 1~2H, the temperature is then lowered to 750℃~800℃, and static pressing and heat preservation are performed again for 1.5~2H, and then cooled to room temperature with the furnace.

[0024] Furthermore, in step S5, the specific steps of coating the insulating solution are: immersing the E-type iron core after sandblasting and polishing in the insulating solution, using the immersion pulling method, repeating 6-10 times, so that the insulating solution is coated on the surface of the E-type iron core; wherein the insulating solution is any one of epoxy resin, polytetrafluoroethylene, polyimide, and polyether sulfone.

[0025] Furthermore, in step S6, the specific steps of the fixed molding method are: take the E-type iron core with the surface coated with insulating solution and place it in a thermosetting molding machine, then set the heating temperature to 380°C~395°C and the insulation time to 8~12 minutes; and obtain the E-type iron core with an insulating coating on the surface.

[0026] The present application also provides an E-type iron core, which is obtained by the above-mentioned method for preparing the E-type iron core.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] (1) During the preparation process of the E-type iron core, the three-dimensional printing method is used to achieve one-to-one precise molding of various complex structures according to the three-dimensional design dimensions of the E-type iron core, thereby solving the technical problem in the prior art that the E-type iron core is limited by the limited three-dimensional structure and the iron core structure under various complex shapes is difficult to mold; and compared with the existing stamping, casting and other processes, when preparing a thinner and lighter E-type iron core structure, the 3D printing technology only needs to adjust the printing thickness parameters of the 3D printing equipment to obtain a thinner and lighter E-type iron core structure. Therefore, the preparation method has low technical difficulty, fewer operating process steps, simpler equipment and lower price, which solves the technical problem in the prior art that a large number of molding steps are often required to prepare a thinner and lighter E-type iron core structure, which will lead to a longer processing cycle and higher preparation cost; at the same time, the method can also realize the one-piece molding of the E-type iron core, greatly improving the yield rate of the E-type iron core; solving the technical problem in the prior art that the iron core sheet is easily brittle fractured when the conventional stamping method is used to prepare the iron core sheet, and has the advantages of high molding progress, simple operation and high yield rate, thus promoting the development of the electromagnetic induction equipment industry.

[0029] (2) During the preparation process of the E-type iron core, the 3D printing technology is used to print an integrally formed E-type iron core. The specific E-type iron core includes multiple E-type iron sheets and a spacer layer, and the spacer layer is arranged between two adjacent E-type iron sheets. The E-type iron core is obtained by an integral molding method, which can not only achieve a higher density of the E-type iron core, but also ensure that multiple E-type iron sheets can be prepared at the same time.

[0030] (3) During the preparation process of the E-type iron core, an integrally formed E-type iron core is obtained by printing using 3D printing technology. The specific E-type iron core includes a plurality of E-type iron sheets and a spacer layer. The spacer layer is arranged between two adjacent E-type iron sheets, and the spacer layer is composed of a plurality of triangular support blocks. The E-type iron core structure has a spacer layer inside, which can improve the magnetic properties of the E-type iron core. The spacer layer is composed of a plurality of triangular support blocks, and the triangular support blocks can be used to improve the overall mechanical properties of the E-type iron core, so that the prepared E-type iron core structure is more stable.

[0031] (4) During the preparation process of the E-type iron core, the sandblasted and polished E-type iron core is immersed in an insulating solution, and the insulating solution is coated on the surface of the E-type iron core by an immersion pulling method. The insulating solution has excellent chemical stability, corrosion resistance, sealing, high lubricity and non-stickiness, electrical insulation and good anti-aging resistance, which effectively improves the service life and insulation effect of the E-type iron core. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The invention is further described using the accompanying drawings, but the embodiments in the accompanying drawings do not constitute any limitation to the invention. A person skilled in the art can obtain other drawings based on the following drawings without creative work.

[0033] Figure 1 1 is a flow chart of the method for preparing the E-type iron core in the embodiment.

[0034] Figure 2 It is a schematic diagram of the structure of the E-type core in Example 1 and Example 2

[0035] Figure 3 yes Figure 2 Sectional view in

[0036] Figure 4 It is a structural schematic diagram of the E-type iron core in Example 3.

[0037] Figure 5 yes Figure 4 Cross-sectional view of .

[0038] Figure 6 It is a top view of the E-type iron sheet and the spacing layer in the E-type iron core in Example 3.

[0039] The figure includes: an E-shaped iron sheet 1, a spacer layer 2, a triangular support block 21, an insulating coating 3, a strip-shaped through hole 4, and an E-shaped sealing cavity 5. DETAILED DESCRIPTION

[0040] The present invention is further described in conjunction with the following examples.

[0041] The specific implementation modes of the present invention are further described below in conjunction with the accompanying drawings to make the technical solutions of the present invention easier to understand and grasp.

[0042] In this embodiment, it should be understood that the terms "middle", "upper", "lower", "top", "right side", "end", "front", "back", "middle", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0043] In addition, in this specific embodiment, if the connection or fixing method between components is not specifically described, the connection or fixing method can be through bolt fixing or pin fixing, or pin shaft connection and the like commonly used in the prior art, and therefore, it is not described in detail in this embodiment.

[0044] The present application provides a method for preparing an E-type iron core, comprising the following steps:

[0045] S1. Design of E-type core model: Use 3D drawing software to obtain the E-type core model;

[0046] S2, 3D printed E-shaped iron core: using 3D printing technology to print an integrated E-shaped iron core, wherein the E-shaped iron core includes a plurality of E-shaped iron sheets 1 and a spacer layer 2, the spacer layer 2 is arranged between two adjacent E-shaped iron sheets 1, and the spacer layer 2 is composed of a plurality of triangular support blocks 21;

[0047] S3, hot isostatic pressing: put the E-type iron core obtained by 3D printing into a hot isostatic pressing furnace, blow high-purity argon gas into the hot isostatic pressing furnace, and pressurize and keep warm under argon conditions;

[0048] S4, sandblasting and grinding: Use the sandblasting and grinding process to clean the sticky powder or impurities on the surface of the E-type iron core after hot isostatic pressing;

[0049] S5, coating the insulating solution: immersing the sandblasted and polished E-type iron core in the insulating solution, and coating the insulating solution on the surface of the E-type iron core by using an immersion and pulling method;

[0050] S6 curing molding: The insulating solution is cured on the surface of the E-type core by heat treatment.

[0051] The method of the present invention is used to prepare an E-type iron core structure with a polytetrafluoroethylene coating, and the designed multi-layer composite iron core structure can be prepared more conveniently and accurately. Different E-type iron sheets 1 are separated by supports, and the E-type iron core and the coating are tightly combined. While ensuring the integrity of the designed E-type iron core structure, the electromagnetic performance of the E-type iron core can also be guaranteed. The polytetrafluoroethylene coating used has excellent insulation, can isolate adjacent layers, and reduce the risk of breakdown. At the same time, the polytetrafluoroethylene coating is resistant to high temperature, corrosion, high lubricity, and non-stickiness, and has a very high service life.

[0052] During the preparation process of the E-type iron core, various complex structures are precisely formed in a one-to-one ratio according to the three-dimensional design size of the E-type iron core through three-dimensional printing, which solves the technical problem that the E-type iron core in the prior art is limited by the limited three-dimensional structure and the iron core structure under various complex shapes is difficult to form; and compared with the existing stamping, casting and other processes, when preparing a thinner and lighter E-type iron core structure, the 3D printing technology only needs to adjust the printing thickness parameters of the 3D printing equipment to obtain a thinner and lighter E-type iron core structure. Therefore, the preparation method has low technical difficulty, fewer operating process steps, simpler equipment and lower price, which solves the technical problem that a large number of forming steps are often required when preparing a thinner and lighter E-type iron core structure in the prior art, which will lead to a longer processing cycle and higher preparation cost; at the same time, the method can also realize the one-piece forming of the E-type iron core, greatly improving the yield rate of the E-type iron core; It solves the technical problem that the conventional stamping method is used to prepare the iron core sheet in the prior art, which is prone to brittle fracture, and has the advantages of high forming progress, simple operation and high yield rate, which promotes the development of the electromagnetic induction equipment industry.

[0053] During the preparation process of the E-type iron core, an integrally formed E-type iron core is obtained by using 3D printing technology. The specific E-type iron core includes multiple E-type iron sheets 1 and a spacer layer 2, and the spacer layer 2 is arranged between two adjacent E-type iron sheets 1. The E-type iron core is obtained by an integral molding method, which can not only achieve a higher density of the E-type iron core, but also ensure that multiple E-type iron sheets 1 can be prepared at the same time.

[0054] During the preparation process of the E-type iron core, 3D printing technology is used to print an integrally formed E-type iron core. The specific E-type iron core includes multiple E-type iron sheets 1 and a spacing layer 2. The spacing layer 2 is arranged between two adjacent E-type iron sheets 1, and the spacing layer 2 is composed of multiple triangular support blocks 21. The E-type iron core structure has a spacing layer 2 inside, which can improve the magnetic properties of the E-type iron core, and the spacing layer 2 is composed of multiple triangular support blocks 21. The triangular support blocks 21 can improve the overall mechanical properties of the E-type iron core, so that the prepared E-type iron core structure is more stable.

[0055] During the preparation process of the E-type iron core, the sandblasted and polished E-type iron core is immersed in an insulating solution, and the insulating solution is coated on the surface of the E-type iron core by an immersion pulling method. The insulating solution has excellent chemical stability, corrosion resistance, sealing, high lubricity and non-stickiness, electrical insulation and good anti-aging resistance, which effectively improves the service life and insulation effect of the E-type iron core.

[0056] In a preferred embodiment, in step S1, the three-dimensional drawing software is any one of Magics, Solidworks, UG, and VG.

[0057] In a preferred embodiment, in step S2, 3D printing the E-type core includes the following sub-steps:

[0058] S21, slicing the three-dimensional E-type core model in step S1 along the axial direction of the finger ring with a layer thickness of 30 to 50 μm, and generating a corresponding 3D model slice file;

[0059] S22, sending the 3D model slice file to the 3D printing system to wait for printing;

[0060] S23. Take FeSi or FeNi alloy powder, sieve the alloy powder to obtain powder with a particle size range of 30 to 45 μm, place the powder in a vacuum drying oven and dry it for 4 hours, and finally pour the dried powder into the 3D printing system to wait for printing; wherein, the mass percentage of Si in the alloy powder FeSi is: 3% to 6.5%; the mass percentage of Ni in the alloy powder FeNi is: 45% to 55%; at this content, the comprehensive soft magnetic properties of the E-type iron core are better.

[0061] S24, taking a stainless steel substrate, wiping its surface with alcohol, installing it in a 3D printing system, then closing the hatch of the 3D printing system, and introducing argon protective gas;

[0062] S25. Setting the printing parameters of the 3D printing system, and starting the 3D printing system to print an integrated E-shaped iron core; wherein the laser power is set to 70-90 W; the printed spot diameter is set to 30-40 μm, the scanning speed is set to 900-1100 mm / s, the powder thickness is set to 0.02-0.04 mm, and the scanning interval is set to 0.05-0.07 mm.

[0063] In a preferred embodiment, in step S2, the thickness of a single E-shaped iron sheet 1 is 300-360 mm; the thickness of a single spacer layer 2 is 60-90 mm;

[0064] The side length of the triangular support block 21 is 60-90 mm, and the side length of the triangular support block 21 is consistent with the thickness of the spacer layer 2; the longitudinal section of the triangular support block 21 is arranged in an equilateral triangle.

[0065] In a preferred embodiment, the triangular support block 21 is horizontally disposed between two adjacent E-shaped iron sheets 1 , and a strip-shaped through hole 4 is formed between a single E-shaped iron sheet 1 and any two adjacent triangular support blocks 21 .

[0066] In a preferred embodiment, the triangular support block 21 is disposed at the edge contours of two adjacent E-shaped iron sheets 1 , and forms an E-shaped sealed cavity 5 between the triangular support block 21 and the two adjacent E-shaped iron sheets 1 .

[0067] In a preferred embodiment, in step S3, the hot isostatic pressing process is argon hot isostatic pressing; the process steps of argon hot isostatic pressing are: first, the E-type iron core obtained by 3D printing is placed in a hot isostatic pressing furnace, and then high-purity argon is blown into the hot isostatic pressing furnace, and under argon conditions, the temperature is set to 850℃~900℃, the pressure is set to 100~110MPa, and after static pressing and heat preservation for 1~2H, the temperature is then lowered to 750℃~800℃, and static pressing and heat preservation are performed again for 1.5~2H, and then cooled to room temperature with the furnace.

[0068] In a preferred embodiment, in step S5, the specific steps of applying the insulating solution are: immersing the E-type iron core after sandblasting and polishing in the insulating solution, using the immersion pulling method, repeating 6-10 times, so that the insulating solution is coated on the surface of the E-type iron core; wherein the insulating solution is any one of epoxy resin, polytetrafluoroethylene, polyimide, and polyether sulfone.

[0069] In a preferred embodiment, in step S6, the specific steps of the fixed molding method are: take the E-type iron core with the surface coated with insulating solution and place it in a thermosetting molding machine, then set the heating temperature to 380°C~395°C and the insulation time to 8~12 minutes; then obtain an E-type iron core with an insulating coating 3 on the surface.

[0070] The present application also provides an E-type iron core, which is obtained by the above-mentioned method for preparing the E-type iron core.

[0071] Example 1

[0072] This embodiment provides a method for preparing an E-type iron core, comprising the following steps:

[0073] Step 1: Use 3D drawing software to obtain an E-type core model; the 3D drawing software is Magics drawing software.

[0074] Step 2: Slice the three-dimensional E-type core model in step S1 along the axial direction of the finger ring with a layer thickness of 30 μm, and generate a corresponding 3D model slice file;

[0075] Step 3: Send the 3D model slice file to the 3D printing system and wait for printing;

[0076] Step 4: Take FeSi or FeNi alloy powder, sieve the alloy powder to obtain powder with a particle size range of 30μm, place the powder in a vacuum drying oven and dry it for 4 hours, and finally pour the dried powder into the 3D printing system to wait for printing; wherein, the mass percentage of Si in the alloy powder FeSi is: 6.5%; the mass percentage of Ni in the alloy powder FeNi is: 55%; at this content, the comprehensive soft magnetic properties of the E-type iron core are better.

[0077] Step 5: Take the stainless steel substrate, wipe its surface with alcohol, install it in the 3D printing system, then close the hatch of the 3D printing system and introduce argon protective gas;

[0078] Step 6: Set the printing parameters of the 3D printing system, and start the 3D printing system to print an integrated E-shaped iron core; the laser power is set to 90W; the printing spot diameter is set to 40μm, the scanning speed is set to 1100mm / s, the powder thickness is 0.04mm, and the scanning spacing is set to 0.07mm.

[0079] The thickness of a single E-shaped iron sheet 1 is 360 mm; the thickness of a single spacer layer 2 is 90 mm.

[0080] The side length of the triangular support block 21 is 90 mm, and the side length of the triangular support block 21 is consistent with the thickness of the spacer layer 2; the longitudinal section of the triangular support block 21 is arranged in an equilateral triangle.

[0081] The triangular support block 21 is horizontally arranged between two adjacent E-shaped iron sheets 1 , and a strip-shaped through hole 4 is formed between a single E-shaped iron sheet 1 and any two adjacent triangular support blocks 21 .

[0082] Step 7: After printing is completed, the remaining unmelted powder is recovered and the powder on the surface of the molded part is removed using a special vacuum cleaner for sampling. Preferably, the obtained E-type core is cut and removed from the stainless steel substrate by wire cutting.

[0083] Step 8: Hot isostatic pressing: put the E-type iron core obtained by 3D printing into a hot isostatic pressing furnace, and blow high-purity argon into the hot isostatic pressing furnace, pressurize and keep warm under argon conditions; the hot isostatic pressing process is argon hot isostatic pressing; the process steps of argon hot isostatic pressing are: first put the E-type iron core obtained by 3D printing into a hot isostatic pressing furnace, and then blow high-purity argon into the hot isostatic pressing furnace, set the temperature to 900°C and the pressure to 110MPa under argon conditions, and then press and keep warm for 2 hours, then lower the temperature to 800°C, press and keep warm for 2 hours again, and then cool to room temperature with the furnace.

[0084] Step 9: Sandblasting: Use the sandblasting process to clean the sticky powder or impurities on the surface of the E-type core after hot isostatic pressing;

[0085] Step 10: Immerse the sandblasted E-type iron core in an insulating solution, and use an immersion and pulling method, repeating 10 times, so that the insulating solution is coated on the surface of the E-type iron core; wherein the insulating solution is any one of epoxy resin, polytetrafluoroethylene, polyimide, and polyethersulfone.

[0086] Step 11: Take the E-type iron core with the surface coated with the insulating solution and place it in a thermosetting molding machine, then set the heating temperature to 395° C. and the insulation time to 12 minutes; then obtain the E-type iron core with the insulating coating 3 on the surface.

[0087] Example 2

[0088] This embodiment provides a method for preparing an E-type iron core, comprising the following steps:

[0089] Step 1: Use 3D drawing software to obtain an E-type core model; the 3D drawing software is Solidworks drawing software.

[0090] Step 2: Slice the three-dimensional E-type core model in step S1 along the axial direction of the finger ring with a layer thickness of 30 to 50 μm, and generate a corresponding 3D model slice file;

[0091] Step 3: Send the 3D model slice file to the 3D printing system and wait for printing;

[0092] Step 4: Take FeSi or FeNi alloy powder, sieve the alloy powder to obtain powder with a particle size range of 30μm, place the powder in a vacuum drying oven and dry it for 4 hours, and finally pour the dried powder into the 3D printing system to wait for printing; wherein, the mass percentage of Si in the alloy powder FeSi is: 3%%; the mass percentage of Ni in the alloy powder FeNi is: 45%; at this content, the comprehensive soft magnetic properties of the E-type iron core are better.

[0093] Step 5: Take the stainless steel substrate, wipe its surface with alcohol, install it in the 3D printing system, then close the hatch of the 3D printing system and introduce argon protective gas;

[0094] Step 6: Set the printing parameters of the 3D printing system, and start the 3D printing system to print an integrated E-shaped iron core; the laser power is set to 70W; the printing spot diameter is set to 30μm, the scanning speed is set to 900mm / s, the powder thickness is 0.02mm, and the scanning spacing is set to 0.05mm.

[0095] The thickness of a single E-shaped iron sheet 1 is 300 mm; the thickness of a single spacer layer 2 is 60 mm.

[0096] The side length of the triangular support block 21 is 60 mm, and the side length of the triangular support block 21 is consistent with the thickness of the spacer layer 2; the longitudinal section of the triangular support block 21 is arranged in an equilateral triangle.

[0097] The triangular support block 21 is horizontally arranged between two adjacent E-shaped iron sheets 1 , and a strip-shaped through hole 4 is formed between a single E-shaped iron sheet 1 and any two adjacent triangular support blocks 21 .

[0098] Step 7: After printing is completed, the remaining unmelted powder is recovered and the powder on the surface of the molded part is removed using a special vacuum cleaner for sampling. Preferably, the obtained E-type core is cut and removed from the stainless steel substrate by wire cutting.

[0099] Step 8: Hot isostatic pressing: put the E-type iron core obtained by 3D printing into a hot isostatic pressing furnace, and blow high-purity argon into the hot isostatic pressing furnace, pressurize and keep warm under argon conditions; the hot isostatic pressing process is argon hot isostatic pressing; the process steps of argon hot isostatic pressing are: first put the E-type iron core obtained by 3D printing into a hot isostatic pressing furnace, and then blow high-purity argon into the hot isostatic pressing furnace, set the temperature to 850℃ and the pressure to 100MPa under argon conditions, and then press and keep warm for 1H, then lower the temperature to 750℃, press and keep warm for 1.5H again, and then cool to room temperature with the furnace.

[0100] Step 9: Sandblasting: Use the sandblasting process to clean the sticky powder or impurities on the surface of the E-type core after hot isostatic pressing;

[0101] Step 10: Immerse the sandblasted E-type iron core in an insulating solution, and use an immersion and pulling method, repeating 6 times, so that the insulating solution is coated on the surface of the E-type iron core; wherein the insulating solution is any one of epoxy resin, polytetrafluoroethylene, polyimide, and polyethersulfone.

[0102] Step 11: Take the E-type iron core with the surface coated with the insulating solution and place it in a thermosetting molding machine, then set the heating temperature to 380° C. and the insulation time to 8 minutes; then obtain the E-type iron core with the insulating coating 3 on the surface.

[0103] Example 3

[0104] This embodiment provides a method for preparing an E-type iron core, comprising the following steps:

[0105] Step 1: Use 3D drawing software to obtain the E-type core model; the 3D drawing software is UG drawing software.

[0106] Step 2: Slice the three-dimensional E-type core model in step S1 along the axial direction of the finger ring with a layer thickness of 40 μm, and generate a corresponding 3D model slice file;

[0107] Step 3: Send the 3D model slice file to the 3D printing system and wait for printing;

[0108] Step 4: Take FeSi or FeNi alloy powder, sieve the alloy powder to obtain powder with a particle size range of 40μm, place the powder in a vacuum drying oven and dry it for 4 hours, and finally pour the dried powder into the 3D printing system to wait for printing; wherein, the mass percentage of Si in the alloy powder FeSi is: 5%; the mass percentage of Ni in the alloy powder FeNi is: 50%; at this content, the comprehensive soft magnetic properties of the E-type iron core are better.

[0109] Step 5: Take the stainless steel substrate, wipe its surface with alcohol, install it in the 3D printing system, then close the hatch of the 3D printing system and introduce argon protective gas;

[0110] Step 6: Set the printing parameters of the 3D printing system, and start the 3D printing system to print an integrated E-shaped iron core; the laser power is set to 80W; the printing spot diameter is set to 35μm, the scanning speed is set to 1000mm / s, the powder thickness is 0.03mm, and the scanning spacing is set to 0.06mm.

[0111] The thickness of a single E-shaped iron sheet 1 is 330 mm; the thickness of a single spacer layer 2 is 75 mm.

[0112] The side length of the triangular support block 21 is 75 mm, and the side length of the triangular support block 21 is consistent with the thickness of the spacer layer 2; the longitudinal section of the triangular support block 21 is arranged in an equilateral triangle.

[0113] The triangular support block 21 is disposed at the edge contours of two adjacent E-shaped iron sheets 1 , and forms an E-shaped sealed cavity 5 between the triangular support block 21 and the two adjacent E-shaped iron sheets 1 .

[0114] Step 7: After printing is completed, the remaining unmelted powder is recovered and the powder on the surface of the molded part is removed using a special vacuum cleaner for sampling. Preferably, the obtained E-type core is cut and removed from the stainless steel substrate by wire cutting.

[0115] Step 8: Hot isostatic pressing: put the E-type iron core obtained by 3D printing into a hot isostatic pressing furnace, and blow high-purity argon into the hot isostatic pressing furnace, pressurize and keep warm under argon conditions; the hot isostatic pressing process is argon hot isostatic pressing; the process steps of argon hot isostatic pressing are: first put the E-type iron core obtained by 3D printing into a hot isostatic pressing furnace, and then blow high-purity argon into the hot isostatic pressing furnace, set the temperature to 800°C and the pressure to 105MPa under argon conditions, and keep warm for 1.5 hours, then lower the temperature to 775°C, keep warm for 1.6 hours again, and cool to room temperature with the furnace.

[0116] Step 9: Sandblasting: Use the sandblasting process to clean the sticky powder or impurities on the surface of the E-type core after hot isostatic pressing;

[0117] Step 10: Immerse the sandblasted E-type iron core in an insulating solution, and use an immersion pulling method, repeating 8 times, so that the insulating solution is coated on the surface of the E-type iron core; wherein the insulating solution is any one of epoxy resin, polytetrafluoroethylene, polyimide, and polyethersulfone.

[0118] Step 11: Take the E-type iron core with the surface coated with the insulating solution and place it in a thermosetting molding machine, then set the heating temperature to 390° C. and the insulation time to 10 minutes; then obtain the E-type iron core with the insulating coating 3 on the surface.

[0119] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention, rather than to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present invention.

Claims

1. A method for preparing an E-type iron core, characterized in that: The following steps are involved: S1. Design of E-type core model: Use 3D drawing software to obtain the E-type core model; S2, 3D printed E-type iron core: an E-type iron core is obtained by printing using 3D printing technology, wherein the E-type iron core comprises a plurality of E-type iron sheets and a spacer layer, the spacer layer is arranged between two adjacent E-type iron sheets, and the spacer layer is composed of a plurality of triangular support blocks; the triangular support blocks are arranged at the edge contours of two adjacent E-type iron sheets, and form an E-shaped sealed cavity between the two adjacent E-type iron sheets; S3, hot isostatic pressing: put the E-type iron core obtained by 3D printing into a hot isostatic pressing furnace, blow high-purity argon gas into the hot isostatic pressing furnace, and pressurize and keep warm under argon gas conditions; S4, sandblasting and grinding: Use the sandblasting and grinding process to clean the sticky powder or impurities on the surface of the E-type iron core after hot isostatic pressing; S5, coating the insulating solution: immersing the sandblasted and polished E-type iron core in the insulating solution, and coating the insulating solution on the surface of the E-type iron core by using an immersion and pulling method; S6 curing molding: The insulating solution is cured on the surface of the E-type core by heat treatment.

2. The method for preparing an E-type iron core according to claim 1, characterized in that: In step S1, the three-dimensional drawing software is any one of Magics, Solidworks, UG and VG.

3. The method for preparing an E-type iron core according to claim 1, characterized in that: In step S2, the 3D printing of the E-type core includes the following sub-steps: S21, slicing the three-dimensional E-type core model in step S1 along the axial direction of the finger ring with a layer thickness of 30 to 50 μm, and generating a corresponding 3D model slice file; S22, sending the 3D model slice file to the 3D printing system to wait for printing; S23, taking FeSi or FeNi alloy powder, first sieving the alloy powder to obtain a powder with a particle size range of 30 to 45 μm, placing the powder in a vacuum drying oven for 4 hours, and finally pouring the dried powder into a 3D printing system to wait for printing; wherein the mass percentage of Si in the alloy powder FeSi is: 3% to 6.5%; the mass percentage of Ni in the alloy powder FeNi is: 45% to 55%; S24, taking a stainless steel substrate, wiping its surface with alcohol, installing it in a 3D printing system, then closing the hatch of the 3D printing system, and introducing argon protective gas; S25. Setting the printing parameters of the 3D printing system, and starting the 3D printing system to print an integrated E-shaped iron core; wherein the laser power is set to 70-90 W; the printed spot diameter is set to 30-40 μm, the scanning speed is set to 900-1100 mm / s, the powder thickness is set to 0.02-0.04 mm, and the scanning interval is set to 0.05-0.07 mm.

4. The method for preparing an E-type iron core according to claim 1, characterized in that: In step S2, the thickness of a single E-shaped iron sheet is 300-360 mm; the thickness of a single spacer layer is 60-90 mm; The side length of the triangular support block is 60-90 mm, and the side length of the triangular support block is consistent with the thickness of the spacing layer; the longitudinal section of the triangular support block is arranged in an equilateral triangle.

5. The method for preparing an E-type iron core according to claim 1 or 4, characterized in that: The triangular support block is horizontally arranged between two adjacent E-shaped iron sheets, and a strip-shaped through hole is formed between a single E-shaped iron sheet and any two adjacent triangular support blocks.

6. The method for preparing an E-type iron core according to claim 1, characterized in that: In step S3, the hot isostatic pressing process is argon hot isostatic pressing; the process steps of the argon hot isostatic pressing are: first put the E-type iron core obtained by 3D printing into a hot isostatic pressing furnace, and then blow high-purity argon into the hot isostatic pressing furnace, set the temperature to 850℃~900℃ under argon conditions, set the pressure to 100~110MPa, and keep the temperature under static pressure for 1~2H. Then, lower the temperature to 750℃~800℃, keep the temperature under static pressure for 1.5H~2H again, and then cool to room temperature with the furnace.

7. The method for preparing an E-type iron core according to claim 1, characterized in that: In step S5, the specific steps of coating the insulating solution are: immersing the E-type iron core after sandblasting and polishing in the insulating solution, using the immersion pulling method, repeating 6-10 times, so that the insulating solution is coated on the surface of the E-type iron core; wherein the insulating solution is any one of epoxy resin, polytetrafluoroethylene, polyimide, and polyether sulfone.

8. The method for preparing an E-type iron core according to claim 1, characterized in that: In step S6, the specific steps of the curing molding method are: take the E-type iron core with the surface coated with insulating solution and place it in a thermal curing molding machine, then set the heating temperature to 380℃~395℃ and the insulation time to 8~12min; then obtain the E-type iron core with the surface having an insulating coating.

9. An E-type iron core, characterized in that: The E-type iron core is obtained by the preparation method of the E-type iron core according to any one of claims 1 to 8.

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