Search

CN-116888290-B - Oriented electrical steel sheet and method for manufacturing same

CN116888290BCN 116888290 BCN116888290 BCN 116888290BCN-116888290-B

Abstract

The oriented electrical steel sheet according to one embodiment of the present invention comprises, in weight%, 2.0 to 4.0% of Si, 0.04 to 0.2% of Mn, 0.010% or less (except 0%), 0.005% or less (except 0%), 0.03 to 0.08% of Sn, 0.01 to 0.2% of Cr, and the balance of Fe and unavoidable impurities, and comprises inclusions of at least one of AlN, (Al, si) N, (Al, si, mn) N, mnS, cuS, al 2 O 3 , the average grain size of the inclusions being 0.5 to 6.0 μm, and the inclusions having a grain size of 6.0 μm or less being 40 to 130/mm 2 .

Inventors

  • Song Daxian
  • LI XIANGYU

Assignees

  • 浦项股份有限公司

Dates

Publication Date
20260512
Application Date
20211217
Priority Date
20201221

Claims (13)

  1. 1. An oriented electrical steel sheet, wherein, The oriented electrical steel sheet comprises, in weight%, 2.0 to 4.0% of Si, 0.04 to 0.2% of Mn, 0.010% or less of N and 0% or less of C, 0.03 to 0.08% of Sn, 0.01 to 0.2% of Cr, and the balance of Fe and unavoidable impurities, Inclusion containing at least one of AlN, (Al, si) N, (Al, si, mn) N, mnS, cuS, al 2 O 3 , Wherein the inclusions have an average particle size of 0.5 to 6.0 μm, The inclusions having a particle diameter of 6.0 μm or less are 40 to 130 inclusions/mm 2 , and Wherein the area fraction of the crystal grains having a grain size of 1mm or less is 10% or less.
  2. 2. The oriented electrical steel sheet according to claim 1, wherein, Further comprises 0.005 to 0.030% by weight of Al.
  3. 3. The oriented electrical steel sheet according to claim 1, wherein, Further comprises 0.010 wt% or less of S.
  4. 4. The oriented electrical steel sheet according to claim 1, wherein, Further comprising P in an amount of 0.0005 to 0.045 wt.%.
  5. 5. The oriented electrical steel sheet according to claim 1, wherein, Further comprises 0.1 wt% or less of Sb.
  6. 6. The oriented electrical steel sheet according to claim 1, wherein, Further comprises at least one of 0.1 wt% or less of Co, 0.1 wt% or less of Ni, and 0.1 wt% or less of Mo.
  7. 7. A method for manufacturing oriented electrical steel sheet, comprising: a step of hot-rolling a slab comprising, in weight%, 2.0 to 4.0% of Si, 0.04 to 0.2% of Mn, 0.010% or less of N and 0% or less of C, 0.001 to 0.04% of C, 0.03 to 0.08% of Sn, 0.01 to 0.2% of Cr, and the balance of Fe and unavoidable impurities, the slab satisfying the following formula 1; Coiling the hot rolled steel plate; a step of directly cooling the coiled hot-rolled steel sheet and then cold-rolling the coiled hot-rolled steel sheet to manufacture a cold-rolled steel sheet; A step of subjecting the cold-rolled steel sheet to a primary recrystallization annealing, and A step of performing secondary recrystallization annealing on the cold-rolled steel sheet after the primary recrystallization annealing, In the winding step, the winding temperature is 740 to 830 ℃, the following formula 2 is satisfied, Wherein the oriented electrical steel sheet comprises inclusions of at least one of AlN, (Al, si) N, (Al, si, mn) N, mnS, cuS, al 2 O 3 , Wherein the average particle diameter of the inclusions is 0.5 to 6.0 μm, the inclusions with a particle diameter of 6.0 μm or less in the inclusions are 40 to 130 pieces/mm 2 , Wherein the area fraction of the crystal grains having a grain size of 1mm or less is 10% or less, [ 1] 0.038 × [Si] - 0.069 – [N] ≤ [C] ≤ 0.038 × [Si] - 0.069 + [N] In formula 1, [ Si ], [ N ] and [ C ] represent the weight% content of Si, N and C in the slab, respectively, [ 2] 90 ≤ (0.038 × [Si] + [N] + [C]) × [CT] ≤ 130 In the formula 2, [ Si ], [ N ], [ C ] respectively represent the weight percent content of Si, N and C in the slab, and [ CT ] represents the coiling temperature in the unit of DEG C.
  8. 8. The method for manufacturing oriented electrical steel sheet according to claim 7, wherein, The step of manufacturing a hot rolled steel sheet is preceded by a step of heating the slab to 1300 ℃ or less.
  9. 9. The method for manufacturing oriented electrical steel sheet according to claim 7, wherein, After the coiling step and before the step of manufacturing the cold-rolled steel sheet, heat treatment of heating from the outside of the steel sheet is not performed.
  10. 10. The method for manufacturing oriented electrical steel sheet according to claim 7, wherein, The step of manufacturing the cold-rolled steel sheet is completed by a step of performing a cold rolling of the hot-rolled steel sheet once.
  11. 11. The method for manufacturing oriented electrical steel sheet according to claim 7, wherein, The primary recrystallization annealing step includes a decarburization step and a nitriding step, The nitriding step is performed after the decarburization step, or The decarburization step is performed after the nitriding step, or The decarburization step and the nitriding step are performed simultaneously.
  12. 12. The method for manufacturing oriented electrical steel sheet according to claim 7, wherein, After the primary recrystallization annealing step, a step of applying an annealing separator is further included.
  13. 13. The method for manufacturing oriented electrical steel sheet according to claim 7, wherein, The secondary recrystallization annealing step is to complete secondary recrystallization at a temperature of 900 ℃ to 1210 ℃.

Description

Oriented electrical steel sheet and method for manufacturing same Technical Field One embodiment of the present invention relates to an oriented electrical steel sheet and a method of manufacturing the same. Specifically, an embodiment of the present invention provides an oriented electrical steel sheet and a manufacturing method capable of suppressing magnetic deterioration even if an annealing process of a hot rolled sheet is omitted by appropriately controlling the content of Si, C, N, cr, sn or the like and appropriately adjusting the coiling temperature in the hot rolling process. Background The oriented electrical steel sheet is a soft magnetic material having a gaussian texture (Goss texture) of {110} <001> of a steel sheet texture with respect to a rolling direction, and thus has excellent magnetic characteristics in one direction or the rolling direction. In order to improve the magnetic properties of oriented electrical steel sheets by characterizing such textures, complicated processes such as composition control in steelmaking, slab reheating and hot rolling process parameter control in hot rolling, annealing heat treatment of hot rolled sheet, cold rolling, primary recrystallization annealing, secondary recrystallization annealing, etc. are required, and very precise and strict management is necessary. Among the above processes, the hot rolled sheet annealing process is a necessary process for stably achieving secondary recrystallization of gaussian oriented grains in the secondary recrystallization annealing process by uniformly controlling uneven microstructure and precipitates of the hot rolled sheet after hot rolling. However, since the hot rolled sheet annealing is a factor of increasing the production cost of the oriented electrical steel sheet, if the microstructure and the precipitates of the hot rolled sheet can be made uniform while omitting the hot rolled sheet annealing, the manufacturing cost generated by the hot rolled sheet annealing process can be reduced and the productivity can be improved. Thermal deviations on the skids (skids) are inevitably generated when the slab is heated, thereby causing precipitates and micro-structure unevenness of the hot rolled sheet. If the hot-rolled sheet annealing is omitted, the aforementioned thermal deviation cannot be reduced, and eventually the magnetic deviation of the finally produced oriented electrical steel sheet becomes more serious, and the magnetic properties are deteriorated. Various attempts have been made to omit the hot rolled sheet annealing, but no technology has been proposed directly for reducing the thermal deviation in the inner slide (skin) of the heating furnace at the time of slab heating, and for solving the precipitate and microstructure non-uniformity. Disclosure of Invention First, the technical problem to be solved One embodiment of the present invention relates to an oriented electrical steel sheet and a method of manufacturing the same. Specifically, an embodiment of the present invention provides an oriented electrical steel sheet and a manufacturing method capable of suppressing magnetic deterioration even if an annealing process of a hot rolled sheet is omitted by appropriately controlling the content of Si, C, N, cr, sn or the like and appropriately adjusting the coiling temperature in the hot rolling process. (II) technical scheme The oriented electrical steel sheet according to an embodiment of the present invention, wherein the oriented electrical steel sheet comprises, in weight%, 2.0 to 4.0% of Si, 0.04 to 0.2% of Mn, 0.010% or less (excluding 0%), 0.005% or less (excluding 0%) of C, 0.03 to 0.08% of Sn, 0.01 to 0.2% of Cr, and the balance of Fe and unavoidable impurities, An inclusion comprising at least one of AlN, (Al, si) N, (Al, si, mn) N, mnS, cuS, al 2O3, the average grain size of the inclusion being 0.5 to 6.0 μm, and the inclusion having a grain size of 6.0 μm or less being 40 to 130 inclusions/mm 2. According to the oriented electrical steel sheet of one embodiment of the present invention, the area fraction of the crystal grains having a grain size of 1mm or less is 10% or less. The oriented electrical steel sheet according to an embodiment of the present invention may further include 0.005 to 0.030 wt% of Al. The oriented electrical steel sheet according to an embodiment of the present invention may further include S0.010 wt% or less. The oriented electrical steel sheet according to an embodiment of the present invention may further include P:0.0005 to 0.045 wt%. The oriented electrical steel sheet according to an embodiment of the present invention may further include 0.1 wt% or less of Sb. The oriented electrical steel sheet according to an embodiment of the present invention may further include one or more of 0.1 wt% or less of Co, 0.1 wt% or less of Ni, and 0.1 wt% or less of Mo. A method for manufacturing an oriented electrical steel sheet according to one embodiment of the present inven