Grain-oriented silicon steel with uniform magnetic properties and laser marking method thereof

Abstract

The application relates to an oriented silicon steel with uniform magnetic properties and a laser marking method thereof, and is applied to the technical field of oriented silicon steel manufacturing, wherein the oriented silicon steel with uniform magnetic properties is provided with superimposed marking lines on a plate surface, the extension direction of the superimposed marking lines is perpendicular to the rolling direction of the oriented silicon steel, the superimposed marking lines comprise an initial marking line and two compensation marking lines, the initial marking line is a continuous marking line penetrating the width direction of the entire oriented silicon steel plate surface, the laser energy borne by the initial marking line decreases from the plate width center point of the silicon steel plate surface to the edges, one compensation marking line extends from the edge of one side of the oriented silicon steel to the plate width center point of the oriented silicon steel plate surface, the other compensation marking line extends from the edge of the other side of the oriented silicon steel to the plate width center point, and the laser energy borne by the compensation marking lines gradually decreases from the edge side of the oriented silicon steel to the plate width center point. In the application, the uniformity of the magnetic properties of the oriented silicon steel obtained through laser compensation marking energy is higher.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of oriented silicon steel manufacturing, and particularly relates to oriented silicon steel with uniform magnetic properties and a laser marking method thereof. BACKGROUND

[0002] Now, green development and energy efficiency upgrading of the power industry have become an important development direction. As a core device in the power transmission system, the loss of the transformer affects the efficiency of power transmission, and the magnetic properties of the oriented silicon steel as a key material in the transformer directly affect the energy efficiency and performance of the transformer.

[0003] In the related art, in order to reduce the iron loss of the oriented silicon steel, that is, to improve the magnetic properties of the oriented silicon steel, the method of improving the grain orientation degree of the oriented silicon steel and reducing the thickness of the plate is usually used to reduce the hysteresis loss and classical eddy current loss, however, with the continuous improvement of the manufacturing technology of the oriented silicon steel, the grain orientation degree of the oriented silicon steel has approached the ideal state, and further reducing the thickness of the plate will greatly increase the production difficulty, and the traditional metallurgical loss reduction effect is very limited, and the magnetic domain refinement technology which reduces the abnormal eddy current loss by refining the magnetic domain has gradually become an important development direction. For example, the patent with the authorization announcement number CN102477484B discloses a method of realizing fast marking by simultaneously and staggeringly marking lines on the upper and lower surfaces of the steel strip by using a highly focused continuous laser beam, so that the iron loss improvement rate reaches 10% to 16%; the patent with the authorization announcement number CN102941413B discloses a method of controlling the heat diffusion and melting phenomenon generated in the laser marking process by forming a composite superimposed groove on the surface of the oriented silicon steel through front and rear laser scanning, so that the finished product lamination coefficient and the surface coating adhesion are good, and the iron loss does not deteriorate after stress relief annealing. However, in the above laser marking method, since the angle between the laser beam and the plate surface changes during the process of scanning the laser beam from one side of the oriented silicon steel plate to the other side, the problem of inconsistent laser energy density is caused, specifically, the energy density of the plate width edge is much lower than that of the plate width center, resulting in uneven marking, thereby causing uneven magnetic properties of the oriented silicon steel plate surface. SUMMARY

[0004] Therefore, it is necessary to provide an oriented silicon steel with uniform magnetic properties and a laser marking method thereof in view of the problem of uneven magnetic properties of the oriented silicon steel plate surface caused by uneven laser marking.

[0005] In a first aspect, the application provides an oriented silicon steel, which has superimposed score lines on a plate surface of the oriented silicon steel, the superimposed score lines extend in a direction perpendicular to a rolling direction of the oriented silicon steel, the superimposed score lines include an initial score line and two compensation score lines, the initial score line is a continuous score line extending through the entire width direction of the plate surface of the oriented silicon steel, the initial score line receives laser energy decreasing from a center point of the plate width of the plate surface of the oriented silicon steel to both edges, one of the compensation score lines extends from one edge of the oriented silicon steel to the center point of the plate width of the plate surface of the oriented silicon steel, the other compensation score line extends from the other edge of the oriented silicon steel to the center point of the plate width, and the compensation score lines receive laser energy gradually decreasing from the edges of the oriented silicon steel to the center point of the plate width.

[0006] Further, the total energy density E of the superimposed score lines at any position receiving twice laser irradiation ranges from 100 to 300 mJ / mm 2 .

[0007] Further, the iron loss improvement rate of the oriented silicon steel after laser scoring is between 11% and 13%, and the magnetic induction loss is between 0 and 0.01 T.

[0008] Further, the difference in iron loss values of the oriented silicon steel plate at different positions along the plate width direction is between 0 and 1%.

[0009] In a second aspect, the application provides a laser scoring method suitable for preparing the oriented silicon steel with uniform magnetic properties provided in the first aspect, and the laser scoring method includes:

[0010] controlling the laser to etch along the plate width direction of the oriented silicon steel from one edge of the plate width to the other edge to obtain the initial score line;

[0011] respectively compensating the initial score line from both ends of the initial score line along the initial score line to the center point of the plate width of the oriented silicon steel to obtain two compensation score lines superimposed on the initial score line, and the compensation score lines and the initial score line superimposed to form the superimposed score lines, and the superimposed score lines extend in a direction perpendicular to the rolling direction of the oriented silicon steel;

[0012] wherein the two compensation score lines receive laser energy gradually decreasing from the edges of the oriented silicon steel at both ends of the initial score line to the center point of the plate width.

[0013] Further, the first laser used for the initial score line and the second laser used for the compensation score line have the same horizontal height, and are sequentially arranged along the rolling direction of the oriented silicon steel, the first laser is closer to the feeding side of the oriented silicon steel than the second laser, and the first laser is located directly above the center line along the rolling direction of the oriented silicon steel, and the second laser has two, one of which is located directly above one edge of the oriented silicon steel, and the other is located directly above the other edge of the oriented silicon steel.

[0014] Further, the first laser and the second laser are both continuous lasers.

[0015] Further, the arrangement height h of the first laser and the second laser and the width L of the oriented silicon steel satisfy the following relationship: h≥0.9L.

[0016] Further, the two compensation score lines overlap each other or have a spacing in the plate width direction at the plate width center position of the plate surface of the oriented silicon steel, and the overlapping length l a is in the range of (0, 3] mm, and the spacing l b is in the range of [0, 5] mm.

[0017] The plate surface of the above-mentioned oriented silicon steel with uniform magnetic properties is provided with superimposed score lines, the extension direction of the superimposed score lines is perpendicular to the rolling direction of the oriented silicon steel, the superimposed score lines include an initial score line and two compensation score lines, the initial score line is a continuous score line penetrating the entire width direction of the plate surface of the oriented silicon steel, the laser energy received by the initial score line decreases from the plate width center point of the plate surface to the edges, one of the compensation score lines extends from one edge of the oriented silicon steel to the plate width center point of the plate surface of the oriented silicon steel, the other compensation score line extends from the other edge of the oriented silicon steel to the plate width center point, and the laser energy received by the compensation score lines gradually decreases from the edge side of the oriented silicon steel to the plate width center point.

[0018] The oriented silicon steel of the present application has the beneficial effects that: on the basis of the initial score line, the oriented silicon steel of the present application superimposes the compensation score line, so that the energy density difference of the laser irradiation at different positions in the plate width direction is small, that is, it is helpful to make the laser energy distribution at any position on the superimposed score line formed finally more uniform, thereby helping to improve the score energy uniformity of the entire plate surface of the oriented silicon steel, and further obtaining the oriented silicon steel product with uniform magnetic properties. BRIEF DESCRIPTION OF DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0020] Figure 1 It is a schematic diagram of the positional relationship between the laser beam and the plate surface during laser irradiation.

[0021] Figure 2 It is a schematic diagram of the change of the light spot when the laser beam with a circular cross-section is scanned and scored.

[0022] Figure 3Fig. 6 is a schematic diagram of the movement of the laser spot on the surface of the silicon steel sheet during the laser scanning process.

[0023] Figure 4 Fig. 7 is a schematic diagram of the laser structure arrangement.

[0024] Figure 5 Fig. 8 is a diagram of the energy density distribution law when different positions on the score line are irradiated by the laser.

[0025] Figure 6 Fig. 9 is a schematic diagram of the sampling position during the magnetic property test.

[0026] Figure 7 Fig. 10 is a schematic diagram of the intersection of the two compensation score lines at the center position of the plate width.

[0027] BRIEF DESCRIPTION OF THE DRAWINGS

[0028] 10, oriented silicon steel; 21, first laser; 22, second laser; 31, initial score line; 32, first compensation score line; 33, second compensation score line; 34, superimposed score line. DETAILED DESCRIPTION

[0029] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific embodiments of the present application will be described in detail below in conjunction with the drawings. In the following description, many specific details are set forth in order to provide a thorough understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the spirit of the present application, so the present application is not limited to the specific embodiments disclosed below.

[0030] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the purpose of facilitating the description of the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0031] In addition, the terms "first" and "second" are only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined with "first" and "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, such as two, three, etc., unless otherwise specifically limited.

[0032] The terms "vertical", "horizontal", "upper", "lower", "left", "right", and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation.

[0033] The laser marking scheme widely used at present is that the laser is fixed, the focal point is ensured to be located on the oriented silicon steel plate surface through reasonable optical path design, and the laser beam rotates at a certain angular velocity around a point when scanning, thereby realizing rapid scanning and marking of the entire plate surface of the oriented silicon steel. However, the above scheme ignores the influence of the change of the angle between the laser beam and the plate surface on the laser energy density at different positions on the marking line.

[0034] Specifically, referring to Figure 1 , Figure 1 is a schematic diagram of the positional relationship between the laser beam and the oriented silicon steel plate surface during laser scanning. During the laser scanning and marking process, the angle between the laser beam and the oriented silicon steel plate surface changes, thereby affecting the spot shape and area size of the laser beam irradiated on the oriented silicon steel plate surface. Referring to Figure 2 , Figure 2 The difference in spot shape at the plate width edge and the plate width center is illustrated by taking a laser beam with a circular cross section as an example. In addition, referring to Figure 3 When the laser beam rotates at a constant speed through two identical angles θ, the time used is equal, but at this time, the distances AP and PB moved by the spot are obviously not equal, which indicates that the speed of the spot moving on the oriented silicon steel plate surface is changing.

[0035] Taking the case that the laser is located at the plate width center of the oriented silicon steel, it is found through research that, during the process that the laser beam scans from one side of the oriented silicon steel plate surface to the other side, the spot area and the spot moving speed change in accordance with the following rules: the spot area first decreases and then increases; the spot moving speed on the oriented silicon steel plate surface first decreases and then increases.

[0036] It should be noted that the spot area S and the spot moving speed v s are calculated by the following formula:

[0037]

[0038] Wherein, a is the length of the spot along the scanning direction when the laser beam is vertically irradiated on the plate surface, with the unit of mm, which is affected by the angle α between the laser beam and the oriented silicon steel plate surface; b is the length of the spot perpendicular to the scanning direction, with the unit of mm, which is not affected by the angle α between the laser beam and the oriented silicon steel plate surface; ω is the angular velocity of the laser beam rotating when scanning the oriented silicon steel plate surface; h is the arrangement height of the laser.

[0039] The calculation formula of the energy density e of the laser beam irradiated on the plate surface is:

[0040]

[0041] wherein P is the output power of the laser, in W; t s is the time that a single point on the oriented silicon steel sheet surface is irradiated by the laser beam, in ms, which can be calculated by .

[0042] According to the above calculation formula, it can be known that the spot area and the spot moving speed are closely related to the energy density of the laser irradiation on the oriented silicon steel sheet surface, and are directly affected by the angle a between the laser beam and the oriented silicon steel sheet surface. This will cause the following problems: with the movement of the spot on the oriented silicon steel sheet surface, the energy density of a groove line irradiated by the laser from one side to the other side of the oriented silicon steel sheet surface will show a trend of first increasing and then decreasing, that is, the energy density of the wide edge of the oriented silicon steel sheet is much lower than that of the center of the sheet width, resulting in poor magnetic property uniformity of the entire oriented silicon steel sheet surface.

[0043] In view of the above problems, with reference to Figure 4 , Figure 4 a schematic diagram of a laser structure arrangement provided by the present application, in which the RD arrow indicates the rolling direction of the oriented silicon steel 10, which is also the length direction and the feeding direction of the oriented silicon steel, and the TD arrow indicates the width direction of the oriented silicon steel 10. In some embodiments, on the basis of arranging the first laser 21 at the center of the sheet width in the first row, one second laser 22 is added on each side edge of the sheet width in the second row, the horizontal height of the first laser 21 and the second laser 22 is consistent, and the first laser 21 and the second laser 22 are sequentially arranged along the rolling direction of the oriented silicon steel 10, the first laser 21 is closer to the feeding side of the oriented silicon steel 10 than the second laser 22, the first laser 21 is used to etch the initial groove line 31, and the second laser 22 is used to etch the compensation groove line. Accordingly, the present application provides a laser grooving method suitable for the oriented silicon steel 10, which comprises: using the compensation grooving method on the surface of the oriented silicon steel 10 to compensate the energy of the initial groove line 31 on the surface of the oriented silicon steel 10, that is, superimposing the compensation groove line on the initial groove line 31 to form the superimposed groove line 34 perpendicular to the rolling direction of the oriented silicon steel 10, wherein the initial groove line 31 is a continuous groove line penetrating through the entire oriented silicon steel 10 sheet, one compensation groove line extends from the edge of one side of the oriented silicon steel to the center point of the sheet width of the oriented silicon steel sheet, and the other compensation groove line extends from the edge of the other side of the oriented silicon steel to the center point of the sheet width of the oriented silicon steel sheet, and the two compensation groove lines are respectively the first compensation groove line 32 and the second compensation groove line 33.

[0044] The initial score line 31 and the compensation score line are parallel to the width direction of the oriented silicon steel 10, that is, perpendicular to the rolling direction of the oriented silicon steel 10. The two second lasers 22 are respectively located on the two sides of the width of the oriented silicon steel 10 plate, and the second laser 22 is located directly above the edge of the width of the oriented silicon steel 10 plate.

[0045] Specifically, in the process of laser scoring of the oriented silicon steel 10, the first laser 21 first preliminarily scores the oriented silicon steel 10 plate along the width direction of the plate surface from left to right or from right to left, to obtain the initial score line 31, and the laser energy received by the initial score line 31 decreases from the center of the plate width to the edges of the plate width. After the initial score line 31 moves to the second laser 22, the two second lasers 22 etch from the edges of the oriented silicon steel 10 plate to the center of the plate width to complete the compensation scoring of the initial score line 31 and obtain the superimposed score line 34. One of the second lasers 22 is used to etch the first compensation score line 32, and the other second laser 22 is used to etch the second compensation score line 33. The laser energy received by the first compensation score line 32 and the second compensation score line 33 decreases from the two ends of the initial score line 31 to the center of the plate width. Since the angle between the laser beam of the second laser 22 and the oriented silicon steel 10 plate surface is smallest at the center of the plate width and largest at the edges of the plate width, the energy density of a score line irradiated by the compensation scoring laser first decreases and then increases from one side of the plate surface to the other side, which is just the opposite of the energy density distribution after scanning and irradiation by the initial scoring laser, so that the energy density of the superimposed score line 34 at the edges of the oriented silicon steel 10 plate width can be consistent with the energy density of the superimposed score line 34 at the center of the oriented silicon steel 10 plate width.

[0046] For example, referring to Figure 4 and Figure 5 , Figure 5 Taking the arrangement height h of the first laser 21 and the second laser 22 as 1080mm and the width L of the oriented silicon steel 10 as 1200mm as an example, the energy density distribution law of the score line at different positions irradiated by the laser is shown. The output power of the first laser 21 and the second laser 22 is the same, and the position with the highest energy density on the score line is taken as 100%. According to the above calculation formula of the energy density of the laser beam irradiated on the oriented silicon steel 10 plate surface, the maximum difference of the energy density at different positions on the initial score line 31 along the width direction of the oriented silicon steel 10 plate is 23.58% without compensation. After the compensation scoring superimposes the energy, the difference of the energy density at different positions on the superimposed score line 34 along the plate width direction is 4.99%. It can be seen that through the effect of compensation scoring, the difference of the energy density at different positions irradiated by the laser along the plate width direction can be effectively reduced.

[0047] Further, the first laser 21 and the second laser 22 are both continuous lasers, so that the first laser 21 and the second laser 22 can stably and continuously output laser energy, and frequent switching and restarting are not required, thereby realizing efficient notching operation and ensuring production efficiency.

[0048] The unnotched oriented silicon steel coil with uniform magnetic properties throughout the plate surface was selected, and laser notching was performed according to the scheme in Table 1. Figure 6 Before and after notching, 500*100 mm single-piece samples were cut at the sampling positions shown in the figure, and magnetic property tests were performed, and the magnetic property results are shown in Table 2.

[0049] Table 1

[0050]

[0051] Note: Since the comparative example 1 does not perform compensation notching, the "total energy density E at any position on the superimposed notching line when irradiated twice by laser" therein represents the energy density irradiated by the initial notching laser (the first laser 21).

[0052] Table 2

[0053]

[0054]

[0055] According to the example 1 and the comparative example 1, using the scheme without compensation notching, the maximum difference of iron loss values at different positions along the plate width direction after notching is more than 0.06 W / kg, while using the scheme with compensation notching, the iron loss values at different positions along the plate width direction after notching tend to be consistent, which indicates that compensation notching can greatly reduce the difference in loss reduction effect at different positions on the plate, and can effectively improve the uniformity of the magnetic properties of the plate.

[0056] Referring to Figure 4 In some embodiments, the following relationship is satisfied between the arrangement height h of the first laser 21 and the width L of the oriented silicon steel 10: h≥0.9L.

[0057] Since the arrangement height of the first laser 21 and the arrangement height of the second laser 22 are consistent, the arrangement height of the second laser 22 and the width of the oriented silicon steel 10 also satisfy the above relationship.

[0058] Specifically, according to the example 2, the comparative example 2 in the above Table 1, and Table 2, when the distance l between the two compensation notching lines along the plate width direction is 0.9L, and the total energy density E at any position on the superimposed notching line 34 when irradiated twice by laser is the same as that of the initial notching laser (the first laser 21), the following relationship is satisfied: b and the total energy density E at any position on the superimposed notching line 34 when irradiated twice by laser is the same as that of the initial notching laser (the first laser 21), the following relationship is satisfied: At the same time, similar loss reduction effects can be obtained at different positions along the width of the plate, the magnetic properties of the plate surface are well uniform, and it can ensure that the laser can completely cover the entire surface of the grain-oriented silicon steel plate 10, avoiding the problem of incomplete marking or uneven coverage due to insufficient laser height, thereby improving the uniformity and stability of the overall magnetic properties of the grain-oriented silicon steel 10; in addition, it can also improve the consistency of marking, reduce the adjustment and correction coefficients in the generation process, thereby improving production efficiency; and when At that time, the iron loss reduction of oriented silicon steel 10 varied significantly at different locations along the width direction, resulting in poor uniformity of the magnetic properties on the plate surface. Therefore, the laser height h and plate width L must satisfy the following condition. The relationship.

[0059] Reference Figure 7 In some embodiments, the two compensation notch lines overlap at the center of the width of the grain-oriented silicon steel 10 plate, and the overlap length is l. a The value range is (0, 3] mm.

[0060] Specifically, according to Examples 3-5 in Table 1, Comparative Examples 3-4, and Table 2 above, in When the ratio and the total energy density E at any position on the superimposed notch line 34 are the same under two laser irradiations, the two compensation notch lines overlap at the center of the plate width. When the overlap length l a When the value range is (0, 3] mm, the edge and center of the plate width can achieve similar loss reduction effects, and the magnetic properties of the plate surface are well uniform; while when the overlap length l of the two compensation notch lines at the center of the plate width of the grain-oriented silicon steel 10 plate is... a When the thickness is greater than 3mm, the difference in damage reduction between the center and edge of the board width is significant. Therefore, when making compensation grooves, the overlap length of the two compensation groove lines should be controlled within a reasonable range.

[0061] Alternatively, in other embodiments, the two compensation notch lines are spaced l apart along the width direction at the center position of the width of the grain-oriented silicon steel 10 plate. b The value range is [0, 5] mm.

[0062] Specifically, according to Examples 3-5 in Table 1, Comparative Examples 3-4, and Table 2 above, in When the ratio and the total energy density E at any position on the superimposed notch line 34 are the same under two laser irradiations, the two compensation notch lines have a gap along the width direction at the center of the plate width. When the gap l b When the value range is [0, 5] mm, the edge and center of the plate width can achieve similar loss reduction effects, and the magnetic properties of the plate surface are well uniform; however, when there is a gap along the plate width direction but l bWhen the thickness is greater than 5mm, the difference in loss reduction between the center and edge of the plate width is significant, and it is impossible to obtain oriented silicon steel products with uniform magnetic properties. Therefore, when performing compensation scoring, the spacing between the two compensation scoring lines along the plate width direction must be controlled within a reasonable range.

[0063] In some embodiments, the total energy density at any position on the superimposed scribe line 34 when subjected to two laser irradiations ranges from 100 to 300 mJ / mm². 2 .

[0064] Specifically, according to Example 6 in Table 1, Comparative Examples 5-6, and Table 2 above, in The ratio and the spacing l between the two compensation notch lines along the width of the plate b Under the same conditions, when any position on the superimposed scribe line 34 is subjected to two laser irradiations, the total energy density E is between 100 and 300 mJ / mm². 2 When E < 100 mJ / mm, the difference in iron loss reduction at different locations along the width of the plate is small, and the uniformity of magnetic properties on the plate surface is good; however, when E < 100 mJ / mm 2 At that time, although the difference in iron loss reduction effect at different positions along the width direction of grain-oriented silicon steel 10 was not significant, the effect of scoring on iron loss reduction was greatly weakened; when E>300mJ / mm 2 At that time, compared with before scoring, the iron loss increased after scoring, and the magnetic induction decreased significantly. This is because the excessive energy caused severe deformation of the grain-oriented silicon steel sheet surface. Therefore, the total energy density when any position on the superimposed scoring line is subjected to two laser irradiations must satisfy 100≤E≤300mJ / mm². 2 .

[0065] The laser marking method of this application compensates for the energy of the initial marking line, which can effectively reduce the difference in energy density when irradiated by laser at different positions along the width of the plate, thereby helping to improve the uniformity of marking energy on the entire grain-oriented silicon steel 10 plate and thus obtaining a grain-oriented silicon steel product with uniform magnetic properties.

[0066] In addition, one embodiment of this application provides an oriented silicon steel, which is produced by any of the above-mentioned laser marking methods. After laser marking compensation, the iron loss improvement rate of the oriented silicon steel plate is between 11% and 13%, the magnetic induction loss is between 0 and 0.01T, and the difference between the iron loss value at the two edges of the oriented silicon steel plate and the iron loss value at the center of the plate is between 0 and 1%.

[0067] Specifically, the oriented silicon steel product prepared by the above laser marking method has high consistency of energy density on the superimposed marking line, and helps to improve the marking uniformity, so that the magnetic property change of the whole surface of the oriented silicon steel is more uniform, and the magnetic property of the finally prepared oriented silicon steel product is uniform and the performance of the transformer applied is good.

[0068] In the description of the present specification, the description referring to the terms "some embodiments", "other embodiments", and the like means that the specific features, structures, materials or characteristics described in connection with the embodiments or examples are included in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example.

[0069] Each of the technical features of the above-described embodiments can be combined arbitrarily, and in order to make the description simple, each of the technical features in the above-described embodiments is not described in all possible combinations, however, as long as the combination of the technical features does not exist contradictory, it should be considered as the scope of the present specification.

[0070] The above-described embodiments only express several implementation manners of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the patent application scope. It should be pointed out that for ordinary skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are all within the protection scope of the present application. Therefore, the patent protection scope of the present application should be subject to the appended claims.

Claims

1. An oriented silicon steel having uniform magnetic properties, characterized by, The plate surface of the oriented silicon steel is provided with superimposed score lines, the extension direction of the superimposed score lines is perpendicular to the rolling direction of the oriented silicon steel, the superimposed score lines comprise an initial score line and two compensation score lines, the initial score line is a continuous score line penetrating the whole width direction of the oriented silicon steel plate surface, the laser energy received by the initial score line decreases from the plate width center point to the edges of the silicon steel plate surface, one of the compensation score lines extends from one side edge of the oriented silicon steel to the plate width center point of the oriented silicon steel plate surface, the other compensation score line extends from the other side edge of the oriented silicon steel to the plate width center point, and the laser energy received by the compensation score line gradually decreases from the edge side of the oriented silicon steel to the plate width center point.

2. The grain-oriented silicon steel having uniform magnetic properties according to claim 1, characterized in that, The total energy density E of the superimposed score line at any position subjected to twice laser irradiation ranges from 100 to 300 mJ / mm 2 .

3. The oriented silicon steel having uniform magnetic properties according to claim 1, wherein, The iron loss improvement rate of the oriented silicon steel after laser scoring is between 11% and 13%, and the magnetic induction loss is between 0 and 0.01T.

4. The oriented silicon steel having uniform magnetic properties of claim 1, wherein, The difference in iron loss value of the oriented silicon steel at different positions along the plate width direction is between 0 and 1%.

5. A laser scribing method suitable for producing the oriented silicon steel having uniform magnetic properties according to any one of claims 1 to 4, characterized in that, Comprise: Control the laser to etch along the plate width direction of the oriented silicon steel from one side of the plate width edge to the other side to obtain an initial score line; Compensate the initial score line from both ends of the initial score line along the initial score line to the plate width center point of the oriented silicon steel to obtain two compensation score lines superimposed on the initial score line, the compensation score line and the initial score line form a superimposed score line after superimposition, and the extension direction of the superimposed score line is perpendicular to the rolling direction of the oriented silicon steel; Wherein, the laser energy received by the two compensation score lines gradually decreases from the edge side of the oriented silicon steel at both ends of the initial score line to the plate width center point.

6. The laser scoring method of claim 5, wherein, The horizontal height of the first laser used for the initial score line and the second laser used for the compensation score line is consistent, and the first laser and the second laser are sequentially arranged along the rolling direction of the oriented silicon steel, the first laser is closer to the feeding side of the oriented silicon steel than the second laser, and the first laser is located directly above the center line along the rolling direction of the oriented silicon steel, and the second laser has two, one of the second laser is located directly above one side edge of the oriented silicon steel, and the other second laser is located directly above the other side edge of the oriented silicon steel.

7. The laser scoring method of claim 6, wherein, The first laser and the second laser are both continuous lasers.

8. The laser scoring method of claim 6, wherein, An arrangement height h of the first laser and the second laser and a width L of the oriented silicon steel satisfy the following relationship: .

9. The laser scoring method according to claim 5 or 6, characterized in that, The two compensation score lines overlap each other at the plate width center position of the oriented silicon steel plate surface, and the overlapping length is in the range of (0, 3] mm.

10. The laser scoring method of claim 5 or 6, wherein, The two compensation score lines exist a distance in the plate width direction at the plate width center position of the oriented silicon steel plate surface, and the distance is in the range of [0, 5] mm.

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