Search

CN-121976121-A - Non-oriented silicon steel for thin ultrahigh-strength high-frequency motor and preparation method thereof

CN121976121ACN 121976121 ACN121976121 ACN 121976121ACN-121976121-A

Abstract

The invention discloses a non-oriented silicon steel for a thin ultrahigh-strength high-frequency motor and a preparation method thereof, wherein the steel comprises the following ：C：≤0.002%、Si：3.1%-4.0%、Mn：0.3%-0.7%、P：≤0.01%、S：≤0.001%、Als：0.5%-1.2%、Sn：0.01%-0.08%、N≤0.002%,Ti≤0.001%,Nb≤0.002%,V≤0.002%, percent of chemical components by weight and the balance of Fe and unavoidable impurities, and meets the requirements of Si eq = [ wSi ] +2, wherein the total mass percent of the steel is 100 percent [wAl]-0.5 [ WMn ]. The technical scheme disclosed by the invention has the advantages that trace alloying elements are not needed to be added, the alloy smelting difficulty can be reduced, the smelting production cost is saved, and meanwhile, the means of increasing the deformation structure and the content of silicon aluminum and manganese elements are adopted, so that the material has the characteristics of high strength, high electromagnetic performance and excellent machinability.

Inventors

  • LI YADONG
  • LI ZHIJIAN
  • HU WANQING
  • GAO ZHENYU
  • CHEN CHUNMEI
  • SONG QINGYANG
  • HOU RUIQIANG
  • LIU WENPENG
  • LI FUQIANG
  • SUN CHAO

Assignees

  • 鞍钢股份有限公司

Dates

Publication Date
20260505
Application Date
20260209

Claims (10)

  1. 1. A non-oriented silicon steel for a thin ultra-high strength high frequency motor is characterized in that the chemical components of the steel are as follows ：C：≤0.002%、Si：3.1%-4.0%、Mn：0.3%-0.7%、P：≤0.01%、S：≤0.001%、Als：0.5%-1.2%、Sn：0.01%-0.08%、N≤0.002%,Ti≤0.001%,Nb≤0.002%,V≤0.002%, and the balance of Fe and unavoidable impurities, and the total mass percentage is 100%, so that the steel meets the requirements of Si eq = [ wSi ] +2 [wAl]-0.5 [wMn]。
  2. 2. The thin ultra-high strength high frequency electrical machine non-oriented silicon steel according to claim 1, wherein the thickness of the finished product of the thin ultra-high strength high frequency electrical machine non-oriented silicon steel is 0.2-0.3 mm.
  3. 3. The thin ultra-high strength high frequency electrical machine non-oriented silicon steel according to claim 1, wherein the yield strength of the thin ultra-high strength high frequency electrical machine non-oriented silicon steel is 900-950 mpa, the tensile strength is 950-1080 mpa, the p 1.0/400 is 44-57 w/kg, and the J 5000 is 1.51-1.53 t.
  4. 4. The method for preparing the non-oriented silicon steel for the thin ultra-high strength high frequency motor according to any one of claims 1 to 3, which is characterized by comprising the following steps of converter smelting-RH vacuum refining-continuous casting-hot rolling-normalizing-cold rolling-annealing; continuous casting, namely adopting an electromagnetic stirring and angle guiding crystallizer to carry out continuous casting, and controlling the equiaxial crystal proportion of a casting blank to be higher than 60%; Hot rolling, namely hot rolling soaking temperature is 1180-1260 ℃, heat preservation time is more than 280min, tapping temperature is 1080-1160 ℃, final rolling temperature is 850-920 ℃, coiling temperature is 650-700 ℃, and rolling thickness of a hot rolled finished product is less than 2.2 mm; Normalizing, namely normalizing the soaking temperature to be 800-850 ℃ and the process speed to be 20-30 m/min to obtain grains with the size of 90-110 mu m; cold rolling; Annealing, namely adopting a micro-tension low-temperature annealing process.
  5. 5. The method according to claim 4, wherein the converter smelting is performed at 1610-1670 ℃ for 30-40 min, the S content in the molten steel is controlled to be 0.001-0.003%, the N content is controlled to be 0.002-0.004%, and the C content is controlled to be 0.001-0.002%.
  6. 6. The method according to claim 4, wherein the RH vacuum refining is performed by refining molten steel at 1500-1580 ℃ for 5-30 min under a vacuum of 0.15-0.2 KPa.
  7. 7. The method for preparing the steel ladle slag through continuous casting is characterized in that the method comprises the steps of carrying out electromagnetic stirring on molten steel after smelting at the frequency of 3-5 Hz to enable the equiaxial crystal proportion of a casting blank to be higher than 60%, and then carrying out continuous casting on the specification of the steel blank with the specification of 230-240 mm multiplied by 1200-1260 mm multiplied by L by using a guide angle crystallizer, wherein the radius of curvature of the guide angle crystallizer is 2-8 m, and the thickness of the steel ladle slag is controlled to be 60-80 mm by adopting a slag baffle during tapping.
  8. 8. The method according to claim 4, wherein the cold rolling is performed by using a twenty-high rolling mill for 5 passes, the total reduction is less than 90%, the first two passes reduction is less than 30%, and the surface defect is monitored in real time by using a surface detection system, and parameters are dynamically adjusted to reduce the surface defect rate to less than 0.1%.
  9. 9. The preparation method of claim 4, wherein the annealing is specifically performed by adjusting the soaking temperature to 700-750 ℃, so that only the internal structure of the material is restored, the microstructure is a fibrous ribbon-shaped structure, and the non-oriented silicon steel is obtained by adopting a micro-tension technology.
  10. 10. The method according to claim 9, wherein the micro-tension used for the annealing is 0.5-0.8 kn.

Description

Non-oriented silicon steel for thin ultrahigh-strength high-frequency motor and preparation method thereof Technical Field The invention belongs to the technical field of non-oriented silicon steel, and particularly relates to non-oriented silicon steel for a thin ultrahigh-strength high-frequency motor and a preparation method thereof, which are particularly suitable for steel plates for high-speed motors of new energy automobiles, unmanned aerial vehicles, aerospace and the like. Background With the deepening of global 'double carbon' target propulsion and electrification wave, a high-frequency motor has become a core power element in the fields of new energy automobiles, industrial servo, aerospace and the like. Its performance determines the energy efficiency, power density and reliability of the terminal equipment. Non-oriented silicon steel is a key soft magnetic material for manufacturing iron cores of motors and generators. With the rapid development of industries such as new energy automobiles and unmanned aerial vehicles, high-frequency, miniaturization and high efficiency are urgently required for driving motors. The motor can be made smaller in size by increasing the frequency, but this leads to a drastic increase in core loss, particularly eddy current loss. According to classical theory. The eddy current loss is proportional to the square of the thickness of the silicon steel sheet, and therefore, thinning the gauge is the most effective way to reduce the high frequency core loss. However, thickness reduction causes a series of technical problems that firstly, the simple thickness reduction reduces the strength of the material, so that the material deforms or breaks under high-speed stamping, stacking and high-speed working conditions, secondly, the electromagnetic performance, particularly magnetic induction, of the thinned material is damaged by component and process adjustment, and finally, defects such as warping, wave and the like are extremely easy to occur in the processing process of a thin-specification product, and the plate shape control difficulty is high. At present, the mode of improving the strength of a material is mainly focused on solid solution strengthening, fine grain strengthening, deformation strengthening, second phase strengthening and other modes. However, conventional fine grain strengthening, strain strengthening and second phase strengthening are not suitable for non-oriented silicon steel because they deteriorate electromagnetic properties, and solid solution strengthening is generally achieved by increasing the silicon-aluminum content, but they deteriorate workability of materials. The prior art mainly focuses on adding alloy elements to adopt a solid solution strengthening mechanism, but the enhanced strength does not meet the requirement of high-frequency motor use, so that the non-oriented silicon steel with thin specification, ultrahigh strength and good electromagnetic performance needs to be prepared to meet the requirement of high-frequency motor use. CN103882288B discloses a high-strength special cold-rolled non-oriented electrical steel and a production method thereof, wherein the steel comprises the following chemical components, by weight, less than or equal to 0.0030% of C, 2.5% -3.0% of Si, 0.10% -0.5% of Mn, 0.005% -0.20% of P, less than or equal to 0.0015% of S, less than or equal to 0.0040% of N, 0.140% -1.10% of Als, and the balance of Fe and unavoidable residual elements. The production method comprises converter smelting, continuous casting, hot rolling, normalizing, cold rolling and annealing. The cold-rolled non-oriented electrical steel produced by the technical scheme is suitable for products with the thickness of a finished plate being larger than 0.5mm, and has the advantages of low coercive force, high hardness, no magnetic aging, high strength, strong striking resistance and excellent electromagnetic performance, but the problem of limited production line exists due to the fact that the continuous casting working procedure of the steel obtained by the technical scheme is a sheet billet with the thickness of ASP of 90-150mm, and the thickness of the finished product is suitable for manufacturing an electromagnetic switch and cannot be widely applied to manufacturing of motors. CN 114107799A discloses a high-strength high-frequency silicon steel thin band plate with excellent electromagnetic performance, wherein the chemical components in the steel are ：C≤0.0027％、Si3.10％～3.35％、Als0.80％～1.2％、Mn0.20％～0.85％、P≤0.050％、S≤0.0020％、N≤0.0020％、Ti≤0.0020％、V≤0.0020％、Nb0.0050％～0.080％, weight percent, and the balance is Fe and unavoidable impurities. The non-oriented silicon steel thin strip product is used for manufacturing a driving motor of a new energy automobile, and has high strength and excellent middle-high frequency electromagnetic property, but the technical scheme adopts a mode of adding Nb microalloy, combines a process to control the quant