CN115679064A - Method for manufacturing oriented electrical steel with excellent surface - Google Patents

Abstract

The invention provides a method for manufacturing oriented electrical steel with excellent surface, which belongs to the technical field of oriented electrical steel manufacturing, and comprises the steps of coating an additive after coating a separant on the oriented electrical steel; the oriented electrical steel strip comprises the following chemical components: from 0.0005 wt.% to 0.05 wt.% Bi; the coating of the release agent comprises: firstly, uniformly coating a separant on the surface of the strip steel, then dividing the surface of the strip steel from the edge to the middle along the width direction into a plurality of coating areas according to the distance from the edge to the edge of the strip steel, coating an additive on the coating areas, wherein the coating amount of the additive in the coating areas closer to the edge of the strip steel is more. The method realizes the differentiation adjustment of different areas by non-uniformly spraying the additive on the surface of the strip steel, so that the quality of the edge part and the middle part can reach the optimal state, thereby improving the surface quality of the oriented electrical steel.

Description

A kind of manufacturing method of grain-oriented electrical steel with excellent surface

technical field

The present application relates to the technical field of oriented electrical steel manufacturing, in particular to a method for manufacturing oriented electrical steel with excellent surface.

Background technique

Oriented silicon steel is a metal functional material, mainly used in the electric power industry. Due to its high technical difficulty, long manufacturing process and strict process requirements, it is often hailed as the "Pearl in the Crown" of the steel industry. Among them, the non-underlayer oriented electrical steel is mainly used as the raw material of ultra-thin strip, the iron core of large generators and drive motors. When used as a raw material for ultra-thin strips, if there is a bottom layer composed of magnesium silicate on the surface of the strip steel, the wear of the roll will be aggravated during the rolling process, and the bottom layer and the metal substrate will be peeled off due to different elongation rates, which will affect the rolling accuracy. , the peeled bottom layer will pollute the rolling oil system; when used as a large generator and drive motor core, if there is a magnesium silicate bottom layer on the surface of the strip, it will greatly damage the life of the stamping abrasive tool, and the number of stamping times may be tens of thousands down to thousands of times. Therefore, the non-underlayer oriented electrical steel requires no underlayer residue on the surface of the strip.

The traditional production of oriented silicon steel without bottom layer adopts the technology of adjusting the release agent formula, that is, the characteristic elements that cause the bottom layer to be loose are mixed into the release agent in the form of additives, and the release agent is evenly coated on the surface of the strip by roller coating, which can realize There is no bottom layer in the main area of the strip. However, during the high-temperature annealing process, the steel coil is heated unevenly, and the reaction degree of the bottom layer in different regions is different. Therefore, while the no bottom layer is well controlled in the middle area of the plate width, residual defects of the bottom layer at the edge are prone to occur. In order to solve the residue of the bottom layer at the edge, the traditional method is to optimize the formula of the release agent and adjust the process of the ring furnace. However, while the residue at the edge is alleviated, it will cause damage to the surface quality of the middle part. Therefore, manufacturers of oriented electrical steel without bottom layer only It can choose to cut off the residual area of the bottom layer at the edge and sacrifice the yield to ensure the delivery quality.

Contents of the invention

The embodiment of the present application provides a method for manufacturing oriented electrical steel with excellent surface, so as to solve the technology that the bottom layer of the non-bottomed oriented steel processed by the existing processing method of coating release agent has residue, large amount of edge trimming, and low yield question.

In the first aspect, the embodiment of the present application provides a method for manufacturing grain-oriented electrical steel with excellent surface, the method includes coating the grain-oriented electrical steel with a release agent and then coating additives;

The chemical composition of the oriented electrical steel strip includes: 0.0005% (weight) to 0.05% (weight) of Bi;

Applying the additive after the coating of the release agent includes: first uniformly coating the release agent on the surface of the strip, and then moving the surface of the strip along the width direction from the edge to the middle according to the distance from the edge of the strip. It is divided into a plurality of coating areas, and the additives are applied to the coating areas, and the coating area closer to the edge of the strip has a larger coating amount of the additive.

Further, the coating area is divided into a first coating area, a second coating area and a third coating area, and the third coating area is farther from the strip edge than the second coating area, The second coating zone is farther from the edge of the strip than the first coating zone, the surface of the strip in the first coating zone is uniformly coated with the additive, and the second coating zone is uniformly coated with the additive. The surface of the steel strip in the coating zone is coated with the additive, and the coating amount of the additive shows a decreasing trend from outside to inside along the width direction of the steel strip. For the surface of the steel strip in the third coating zone Apply the additive evenly.

Further, the coating of the additive on the surface of the steel strip in the second coating area and the coating amount of the additive shows a decreasing trend from outside to inside along the width direction of the strip, including:

According to Wp and W ₀ , coating additives on the surface of the steel strip in the second coating zone in a decreasing trend from outside to inside along the width direction of the strip,

Wherein, Wp represents the distance between the coating site and the strip edge, and W ₀ represents the actual residual width of the edge of the non-underlayer oriented electrical steel. Further, the coating of the additive on the surface of the steel strip in the second coating area and the coating amount of the additive shows a decreasing trend from outside to inside along the width direction of the strip, including:

The strip surface of the second coating area is coated with additives from the critical line with the first coating area and according to the coating amount shown in expression 1, and the second coating area is to satisfy The area where W ₀ ≤W _p ≤W ₀ +200;

Expression 1:

In the formula, m represents the amount of coating, Wp represents the distance between the coating site and the edge of the strip, in mm, and the W ₀ is the actual edge residual width of the non-underlayer oriented electrical steel, in mm, and the _ma is the coating amount of the first coating area, which is set at 15-50 g/m ² , and the m _b is the coating amount of the third coating area, which is set at 11-27 g/m ² . Further, the uniform coating of the additive on the strip surface of the first coating zone includes:

Uniformly coating the surface of the steel strip in the first coating area with an additive with a mass of _ma , where the _ma is set to 15-50 g/m ² ;

Wherein, the first coating area is an area satisfying Wp<W ₀ , the W _p represents the distance from the coating position to the strip edge, the W represents the width of the strip steel, and the W ₀ represents the oriented electrical steel without underlayer the actual edge residual width, and the

Further, the uniform coating of the additive on the strip surface of the third coating zone includes:

Uniformly coating the surface of the steel strip in the third coating area with an additive having a mass of m _b , where m _b is set to 11-27 g/m ² ; and _ma > m _b ;

的区域，所述W_p表示涂覆位置距所述带钢边缘距离，所述W表示所述带钢宽度，所述W₀表示所述无底层取向电工钢实际边部残留宽度，且所述

Wherein, the third coating area is to satisfy

The W _p represents the distance from the coating position to the edge of the strip, the W represents the width of the strip, the W ₀ represents the actual edge residual width of the non-underlayer oriented electrical steel, and the

Further, the release agent component is a mixture of silicon steel grade MgO and Al ₂ O ₃ , and the mass fraction of MgO in the mixture is 20%-100%.

Further, the additive is formed by mixing component A with water, and the component A is NaCl, KCl, MgCl ₂ , ZnCl 2 , BaCl ₂ , SrCl _{2 ,} NH ₄ Cl, MnCl ₂ , CaCl ₂ , BiOCl, At least one of SbOCl, Bi(NO ₃ ) ₂ , Cu(NO ₃ ) ₂ , NaNO ₃ , NH ₄ NO ₃ ; the concentration of the additive is 5%-10%.

Further, the droplet diameter of the additive coated is 10-300 μm.

Further, the coating of additives on the coating area includes:

The additive is applied to the coated zone of one and/or both surfaces of the strip.

Compared with the prior art, the above-mentioned technical solutions provided by the embodiments of the present application have the following advantages:

The embodiment of the present application provides a method for manufacturing oriented electrical steel with excellent surface. By adding Bi element to oriented silicon steel, the method can inhibit the formation of oxide film during the decarburization annealing process, and at the same time change the SiO in the oxide film. The shape of ₂ makes the air permeability between the steel plate layers worse during high temperature annealing. At the same time, during the high temperature annealing process, Bi diffuses from the steel plate matrix to the outside atmosphere in the form of steam bubbles. The poor air permeability between the steel plate layers makes it difficult for Bi steam to escape. It will corrode the magnesium silicate bottom layer that has been formed on the surface of the steel plate substrate, and at the same time, it will easily cause the interface between the steel plate substrate and the bottom layer to expand, so that the magnesium silicate bottom layer is easy to peel off during the subsequent pickling process. Oriented silicon steel at the bottom layer; and through non-uniform coating of additives on the strip, the amount of coating on the edge is greater than that in the middle, so as to achieve differential adjustment in different areas, so that the quality of the edge and middle can reach the best state, thereby reducing the bottom residue , reduce the trimming amount and increase the yield.

Description of drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and together with the description serve to explain the principles of the invention.

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, for those of ordinary skill in the art, In other words, other drawings can also be obtained from these drawings without paying creative labor.

Fig. 1 is the schematic diagram of the strip spraying device in the oriented electrical steel manufacturing method with excellent surface provided by the embodiment of the present application;

Fig. 2 is a schematic diagram of the strip spraying positions and the corresponding spraying amounts in the manufacturing method of grain-oriented electrical steel with excellent surface provided by the embodiment of the present application.

Detailed ways

In order to make the purposes, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments It is a part of the embodiments of this application, but not all of them. Based on the embodiments in the present application, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present application.

Grain-oriented electrical steel without underlayer is mainly used as raw material for extremely thin strips, iron cores for large generators and drive motors. When used as a raw material for ultra-thin strips, if there is a bottom layer composed of magnesium silicate on the surface of the strip steel, the wear of the roll will be aggravated during the rolling process, and the bottom layer and the metal substrate will be peeled off due to different elongation rates, which will affect the rolling accuracy. , the peeled bottom layer will pollute the rolling oil system; when used as a large generator and drive motor core, if there is a magnesium silicate bottom layer on the surface of the strip, it will greatly damage the life of the stamping abrasive tool, and the number of stamping times may be tens of thousands down to thousands of times. Therefore, the non-underlayer oriented electrical steel requires no underlayer residue on the surface of the strip.

The traditional production of oriented silicon steel without bottom layer adopts the technology of adjusting the release agent formula, that is, the characteristic elements that cause the bottom layer to be loose are mixed into the release agent in the form of additives, and the release agent is evenly coated on the surface of the strip by roller coating, which can realize There is no bottom layer in the main area of the strip. However, during the high-temperature annealing process, the steel coil is heated unevenly, and the reaction degree of the bottom layer in different regions is different. Therefore, while the no bottom layer is well controlled in the middle area of the plate width, residual defects of the bottom layer at the edge are prone to occur. In order to solve the residue of the bottom layer at the edge, the traditional method is to optimize the formula of the release agent and adjust the process of the ring furnace. However, while the residue at the edge is alleviated, it will cause damage to the surface quality of the middle part. Therefore, manufacturers of oriented electrical steel without bottom layer only It can choose to cut off the residual area of the bottom layer at the edge and sacrifice the yield to ensure the delivery quality.

In view of this, the present application provides a method for manufacturing grain-oriented electrical steel with excellent surface, which can effectively solve the above-mentioned problems existing in the existing bottom-free optimization method.

The technical solutions provided by the embodiments of the present invention are to solve the above-mentioned technical problems, and the general idea is as follows:

The embodiment of the present application provides a method for manufacturing oriented electrical steel with excellent surface to solve the technical problems of residual bottom layer at the edge of oriented steel without bottom layer processed by the existing processing method, large amount of edge trimming, and low yield.

In the first aspect, the embodiment of the present application provides a method for manufacturing grain-oriented electrical steel with excellent surface. The method applies a release agent to the grain-oriented electrical steel and then coats additives;

The chemical composition of the oriented electrical steel strip includes: 0.0005% (weight) to 0.05% (weight) of Bi;

Applying the additive after the coating of the release agent includes: first uniformly coating the release agent on the surface of the strip, and then moving the surface of the strip along the width direction from the edge to the middle according to the distance from the edge of the strip. It is divided into a plurality of coating areas, and the additives are applied to the coating areas, and the coating area closer to the edge of the strip has a larger coating amount of the additive.

The embodiment of the present application provides a method for manufacturing oriented electrical steel with excellent surface. By adding Bi element to oriented silicon steel, the method can inhibit the formation of oxide film during the decarburization annealing process, and at the same time change the SiO in the oxide film. The shape of ₂ makes the air permeability between the steel plate layers worse during high temperature annealing. At the same time, during the high temperature annealing process, Bi diffuses from the steel plate matrix to the outside atmosphere in the form of steam bubbles. The poor air permeability between the steel plate layers makes it difficult for Bi steam to escape. It will corrode the magnesium silicate bottom layer that has been formed on the surface of the steel plate substrate, and at the same time, it will easily cause the interface between the steel plate substrate and the bottom layer to expand, so that the magnesium silicate bottom layer is easy to peel off during the subsequent pickling process. Oriented silicon steel at the bottom layer; and through non-uniform coating of additives on the strip, the amount of coating on the edge is greater than that in the middle, so as to achieve differential adjustment in different areas, so that the quality of the edge and middle can reach the best state, thereby reducing the bottom residue , reduce the trimming amount and increase the yield.

It should be noted that, as shown in FIG. 1 , the coating of the additive of the present application can be before the drying oven, after the drying oven, or before and after the drying oven. The oriented electrical steel manufacturing method of the present application also includes steelmaking, hot rolling, normalizing annealing, cold rolling, decarburization and nitriding annealing, high temperature annealing, stretching leveling annealing and coating insulating coating. technology, and will not be described in detail in this application.

As an implementation manner of an embodiment of the present invention, the coating area is divided into a first coating area, a second coating area and a third coating area, and the distance from the third coating area to the edge of the steel strip is less than the specified The second spraying zone is farther away, the second coating zone is farther away from the strip edge than the first coating zone, and the strip surface in the first coating zone is uniformly coated with the The additive is applied to the surface of the steel strip in the second coating area, and the coating amount of the additive shows a decreasing trend from outside to inside along the width direction of the strip, and the third coating The strip surface in the coating zone is uniformly coated with the additive.

In this application, the bottom layer residue is the heaviest at the edge of the strip, and the quality of the bottom layer in the middle is the best. By setting the coating amount gradually in the second coating area, the quality of both the edge and the middle can reach the best state, and the straight line can be avoided. The molding edge coating forms a corresponding dividing line on the finished product, which affects the apparent quality of the product and is not easily accepted by users.

As an implementation manner of an embodiment of the present invention, the additive is coated on the surface of the steel strip in the second coating area, and the coating amount of the additive is from outside to inside along the width direction of the strip. There is a decreasing trend, including:

According to Wp and W ₀ , coating additives on the surface of the steel strip in the second coating zone in a decreasing trend from outside to inside along the width direction of the strip,

Wherein, Wp represents the distance between the coating site and the strip edge, and W ₀ represents the actual residual width of the edge of the non-underlayer oriented electrical steel.

As an implementation manner of an embodiment of the present invention, the additive is coated on the surface of the steel strip in the second coating area, and the coating amount of the additive is from outside to inside along the width direction of the strip. There is a decreasing trend, including:

The strip surface of the second coating area is coated with additives from the critical line with the first coating area and according to the coating amount shown in expression 1, and the second coating area is to satisfy The area where W ₀ ≤W _p ≤W ₀ +200;

Expression 1:

In the formula, m represents the amount of coating, Wp represents the distance between the coating site and the edge of the strip, in mm, and the W ₀ is the actual edge residual width of the non-underlayer oriented electrical steel, in mm, and the _ma is the coating amount of the first coating area, which is set at 15-50 g/m ² , and the m _b is the coating amount of the third coating area, which is set at 11-27 g/m ² .

In this application, if the amount of coating is too small and the content of characteristic elements is small, the effect of loosening the bottom layer and improving the residual defects of the bottom layer cannot be achieved; The protective effect of the precipitates causes the precipitates to mature rapidly in advance and the magnetic properties deteriorate. Therefore, the coating amount must be controlled within a certain reasonable range.

The amount of the second coating area is to ensure that the second edge of the plate width meets the quality requirements, and there is no obvious boundary mark with the edges of the first and third spraying areas. Select an area 200mm away from the residual area of the edge for gradient coating, which can effectively prevent the appearance of the dividing line and ensure the best state of the central area.

As an implementation manner of an embodiment of the present invention, the uniform coating of the additive on the strip surface of the first coating zone includes:

Uniformly coating the surface of the steel strip in the first coating area with an additive with a mass of _ma , where the _ma is set to 15-50 g/m ² ;

Wherein, the first coating area is an area satisfying Wp<W ₀ , the W _p represents the distance from the coating position to the strip edge, the W represents the width of the strip steel, and the W ₀ represents the oriented electrical steel without underlayer the actual edge residual width, and the

In this application, the amount of the first spraying area is to ensure that the wide edge of the board meets the quality requirements.

As an implementation manner of an embodiment of the present invention, the uniform coating of the additive on the strip surface of the third coating zone includes:

Uniformly coating the surface of the steel strip in the third coating area with an additive having a mass of m _b , where m _b is set to 11-27 g/m ² ; and _ma > m _b ;

的区域，所述W_p表示涂覆位置距所述带钢边缘距离，所述W表示所述带钢宽度，所述W₀表示所述无底层取向电工钢实际边部残留宽度，且所述

Wherein, the third coating area is to satisfy

The W _p represents the distance from the coating position to the edge of the strip, the W represents the width of the strip, the W ₀ represents the actual edge residual width of the non-underlayer oriented electrical steel, and the

In this application, the amount of the third spraying area is to ensure that the middle part of the board width meets the quality requirements.

As an implementation manner of the embodiment of the present invention, the release agent component is a mixture of silicon steel grade MgO and Al ₂ O ₃ , and the mass fraction of MgO in the mixture is 20%-100%.

As an implementation mode of the embodiment of the present invention, the additive is formed by mixing component A with water, and the component A is NaCl, KCl, MgCl ₂ , ZnCl ₂ , BaCl ₂ , SrCl ₂ , NH ₄ Cl, At least one of MnCl ₂ , CaCl ₂ , BiOCl, SbOCl, Bi(NO ₃ ) ₂ , Cu(NO ₃ ) ₂ , NaNO ₃ , NH ₄ NO ₃ ; the concentration of the additive is 5%-10%.

In this application, the additive is a ^Cl- or ^NO3- compound, or a compound that can form an acidic substance with H ⁺ ions. During the high-temperature annealing process, the bottom layer is corroded by the formed acidic atmosphere such as HCl or HNO ₃ , causing the bottom layer to be loose. , the acid solution is easy to invade the inside of the bottom layer during subsequent pickling, which is convenient for the bottom layer to peel off the steel plate substrate. If the concentration of additives is too low, the amount of spray required is too large, the strip steel is not easy to dry, and the water introduced into the strip steel is too much, which will easily cause water vapor mark defects; if the concentration of additives is too high, the carrier solution is too small, and uneven spraying will easily occur It appears as a point defect on the finished product. Therefore, the additive concentration value should be within an appropriate range.

As an implementation manner of the embodiment of the present invention, the particle size of the droplet coated with the additive is 10-300 μm.

In this application, the particle size of the droplet coated with the additive is too small, and the droplet is easily suspended in the environment under the high-speed operation of the strip steel, and cannot reach the surface of the strip steel; Uniform phenomenon, the strip surface is easy to form point defects. By controlling the droplet size of the additive, the coating effect is optimized.

As an implementation manner of the embodiments of the present invention, the coating of additives on the coating area includes:

The additive is applied to the coated zone of one and/or both surfaces of the strip.

Below in conjunction with specific embodiment, further illustrate the present invention. It should be understood that these examples are only used to illustrate the present invention and are not intended to limit the scope of the present invention. The experimental methods not indicating specific conditions in the following examples are usually measured according to national standards. If there is no corresponding national standard, proceed according to general international standards, conventional conditions, or the conditions suggested by the manufacturer.

Example 1

This example provides a method for manufacturing oriented electrical steel with excellent surface, specifically: after the cast slab is heated in a high-temperature annealing furnace at 1150°C, it is hot-rolled to 2.5mm, annealed in two stages in a normalized annealing furnace, and then cold-rolled to 0.23mm. Next, the steel strip is decarburized and nitriding annealed sequentially, the entire surface is uniformly rolled with release agent (MgO slurry), sprayed with additives, coiled, and then the steel coil is changed from horizontal to vertical, and enters a high-temperature annealing furnace for a maximum temperature of 1200°C. Annealing, after being released from the furnace, it will be stress-relieved annealed and coated with insulating coating by the heat-stretching and leveling unit.

Among them, the additive is sprayed on one side of the upper surface of the strip along the width direction of the strip, and the calculation formula of the spraying amount m (g/m ² ) is

Wherein, Wp represents the distance between the spraying site and the strip edge, in mm;

The spacer is mixed with NaCl ₂ and BiOCl at a mass ratio of 7:3, and then dissolved in water with a concentration of 8%.

The chemical composition of low temperature high magnetic induction grain oriented silicon steel used in this example is calculated by mass fraction: C: 0.052%, Si: 3.0%, Mn: 0.08%, S: 0.010%, Als: 0.0245%, N: 0.0099%, Bi: 0.0045%, Sn: 0.20%, Cr: 0.05%, Cu: 0.25%, and the rest are Fe and unavoidable impurity elements.

Example 2

This example provides a method for manufacturing oriented electrical steel with excellent surface, specifically: after the cast slab is heated in a high-temperature annealing furnace at 1150°C, it is hot-rolled to 2.5mm, annealed in two stages in a normalized annealing furnace, and then cold-rolled to 0.23mm. Next, the steel strip is decarburized and nitriding annealed sequentially, the entire surface is uniformly rolled with release agent (MgO slurry), sprayed with additives, coiled, and then the steel coil is changed from horizontal to vertical, and enters a high-temperature annealing furnace for a maximum temperature of 1200°C. Annealing, after being released from the furnace, it will be stress-relieved annealed and coated with insulating coating by the heat-stretching and leveling unit.

Among them, the additive is sprayed on both sides of the upper and lower surfaces of the strip along the width direction of the strip, and the calculation formula of the spraying amount m (g/m ² ) is

Wherein, Wp represents the distance between the spraying site and the strip edge, in mm;

The spacer is mixed with MgCl ₂ , SbOCl and NH ₄ NO ₃ at a mass ratio of 1:2:7, and then dissolved in water with a concentration of 7%.

The chemical composition of low temperature high magnetic induction grain oriented silicon steel used in this example is calculated by mass fraction: C: 0.052%, Si: 3.0%, Mn: 0.08%, S: 0.010%, Als: 0.0245%, N: 0.0099%, Bi: 0.0005%, Sn: 0.20%, Cr: 0.05%, Cu: 0.25%, and the rest are Fe and unavoidable impurity elements.

Example 3

This example provides a method for manufacturing oriented electrical steel with excellent surface, specifically: after the cast slab is heated in a high-temperature annealing furnace at 1150°C, it is hot-rolled to 2.5mm, annealed in two stages in a normalized annealing furnace, and then cold-rolled to 0.23mm. Next, the steel strip is decarburized and nitriding annealed sequentially, the entire surface is uniformly rolled with release agent (MgO slurry), sprayed with additives, coiled, and then the steel coil is changed from horizontal to vertical, and enters a high-temperature annealing furnace for a maximum temperature of 1200°C. Annealing, after being released from the furnace, it will be stress-relieved annealed and coated with insulating coating by the heat-stretching and leveling unit.

Among them, the additive is sprayed on one side of the lower surface of the strip along the width direction of the strip, and the calculation formula of the spraying amount m (g/m ² ) is

Wherein, Wp represents the distance between the spraying site and the strip edge, in mm;

The spacer is mixed with ZnCl ₂ , SrCl ₂ and Cu(NO ₃ ) ₂ in a mass ratio of 3:2:5, and then dissolved in water with a concentration of 8%.

The chemical composition of low temperature high magnetic induction grain oriented silicon steel used in this example is calculated by mass fraction: C: 0.052%, Si: 3.0%, Mn: 0.08%, S: 0.010%, Als: 0.0245%, N: 0.0099%, Bi: 0.05%, Sn: 0.20%, Cr: 0.05%, Cu: 0.25%, and the rest are Fe and unavoidable impurity elements.

Comparative example 1

The spraying additive in embodiment 1 is canceled, and all the other are identical with embodiment 1.

Comparative example 2

The additive spray amount m (g/m ² ) in embodiment 1 is changed into:

其余与实施例1相同。

All the other are identical with embodiment 1.

Comparative example 3

Change the additive concentration in embodiment 2 to 20%, all the other are identical with embodiment 2.

The implementation effect of table 1 embodiment and comparative example

To sum up, the manufacturing method of grain-oriented electrical steel with excellent surface provided by the present invention aims at the generation characteristics of grain-oriented steel without bottom layer, and adopts segmented and gradual control mode, which can effectively realize the differential adjustment of defect area and normal area, so that the edge The quality of the bottom and middle parts has reached the best state without bottom layer, ensuring the uniform quality of the board surface.

It should be noted that in this article, relative terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply these No such actual relationship or order exists between entities or operations. Furthermore, the term "comprises", "comprises" or any other variation thereof is intended to cover a non-exclusive inclusion such that a process, method, article, or apparatus comprising a set of elements includes not only those elements, but also includes elements not expressly listed. other elements of or also include elements inherent in such a process, method, article, or device. Without further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article or apparatus comprising said element.

The above descriptions are only specific embodiments of the present invention, so that those skilled in the art can understand or implement the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Accordingly, the present invention will not be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims (10)

1. A method for manufacturing oriented electrical steel with excellent surface, is characterized in that, said method comprises coating additive after said oriented electrical steel is coated with release agent; The chemical composition of the oriented electrical steel strip includes: 0.0005% (weight) to 0.05% (weight) of Bi; Applying the additive after the coating of the release agent includes: first uniformly coating the release agent on the surface of the strip, and then moving the surface of the strip along the width direction from the edge to the middle according to the distance from the edge of the strip. It is divided into a plurality of coating areas, and the additives are applied to the coating areas, and the coating area closer to the edge of the strip has a larger coating amount of the additive. 2. The method for manufacturing grain-oriented electrical steel with excellent surface according to claim 1, wherein the coating area is divided into a first coating area, a second coating area and a third coating area, and the third coating area is The coating area is farther from the strip edge than the second spraying area, and the second coating area is farther from the strip edge than the first coating area, and the first coating The strip surface of the second coating zone is uniformly coated with the additive, the strip surface of the second coating zone is coated with the additive, and the coating amount of the additive is from outward to outward along the width direction of the strip. The inside shows a decreasing trend, and the additive is evenly coated on the surface of the steel strip in the third coating zone. 3. The method for manufacturing grain-oriented electrical steel with excellent surface according to claim 2, characterized in that, the additive is coated on the strip surface of the second coating zone and the coating of the additive is The amount shows a decreasing trend from outside to inside along the strip width direction, including: According to Wp and W ₀ , coating additives on the surface of the steel strip in the second coating zone in a decreasing trend from outside to inside along the width direction of the strip, Wherein, Wp represents the distance between the coating site and the strip edge, and W ₀ represents the actual residual width of the edge of the non-underlayer oriented electrical steel. 4. according to claim 2 or 3 described surface-oriented grain-oriented electrical steel manufacturing method, it is characterized in that, The coating of the additive on the surface of the steel strip in the second coating area and the coating amount of the additive shows a decreasing trend from outside to inside along the width direction of the strip, including: The strip surface of the second coating area is coated with additives from the critical line with the first coating area and according to the coating amount shown in expression 1, and the second coating area is to satisfy The area where W ₀ ≤W _p ≤W ₀ +200; Expression 1:

In the formula, m represents the coating amount, Wp represents the distance between the coating site and the edge of the strip steel, in mm, and the _W0 is the actual edge residual width of the oriented electrical steel without bottom layer, in mm, and the described

The _ma is the coating amount of the first coating area, which is set at 15-50 g/m ² , and the m _b is the coating amount of the third coating area, which is set at 11-27 g/m ² . 5. the method for manufacturing grain-oriented electrical steel with excellent surface according to claim 2, characterized in that, The uniform coating of the additive on the strip surface of the first coating zone includes: Uniformly coating the surface of the steel strip in the first coating area with an additive with a mass of _ma , where the _ma is set to 15-50 g/m ² ; Wherein, the first coating area is an area satisfying Wp<W ₀ , the W _p represents the distance from the coating position to the strip edge, the W represents the width of the strip steel, and the W ₀ represents the oriented electrical steel without underlayer the actual edge residual width, and the

6. the method for manufacturing grain-oriented electrical steel with excellent surface according to claim 2, characterized in that, The uniform coating of the additive on the strip surface of the third coating zone includes: Uniformly coating the surface of the steel strip in the third coating area with an additive having a mass of m _b , where m _b is set to 11-27 g/m ² ; and _ma > m _b ; Wherein, the third coating area is to satisfy

The W _p represents the distance from the coating position to the edge of the strip, the W represents the width of the strip, the W ₀ represents the actual edge residual width of the non-underlayer oriented electrical steel, and the

7. The method for manufacturing grain-oriented electrical steel with excellent surface according to claim 1, characterized in that, the release agent composition is a mixture of silicon steel grade MgO and Al ₂ O ₃ , and the mass fraction of MgO in the mixture is 20%- 100%. 8. The method for producing grain-oriented electrical steel with excellent surface according to any one of claims 1 to 7, characterized in that the additive is formed by mixing component A with water, and the component A is NaCl, KCl, At least one of MgCl ₂ , ZnCl ₂ , BaCl ₂ , SrCl ₂ , NH ₄ Cl, MnCl ₂ , CaCl ₂ , BiOCl, SbOCl, Bi(NO ₃ ) ₂ , Cu(NO ₃ ) ₂ , NaNO ₃ , NH ₄ NO ₃ One; the concentration of the additive is 5%-10%. 9 . The method for producing grain-oriented electrical steel with excellent surface according to claim 1 , characterized in that the particle size of the droplets coated with the additives is 10-300 μm. 10. The method for manufacturing grain-oriented electrical steel with excellent surface according to claim 1, characterized in that, the coating of additives on the coating area comprises: The additive is applied to the coated zone of one and/or both surfaces of the strip.

Images