JP4669457B2 - Electrical component comprising a magnetic steel sheet having a multilayer coating with excellent film adhesion and good magnetic properties, and its manufacturing method - Google Patents

Description

  The present invention relates to an electrical component having a magnetic steel plate processed into a predetermined shape, such as a stator / rotor of a motor or an iron core of a transformer, as a constituent member, and a manufacturing method thereof. However, the present invention relates to an electrical component which has a good film by a simple film formation process and whose iron loss is greatly reduced, and a method for manufacturing the same.

  Electrical steel sheets used for motors and transformer parts are usually processed into a predetermined shape and stacked for use, but if the stacked steel sheets are electrically short-circuited, the effect of using thin electrical steel sheets Therefore, as shown in Patent Document 1, an insulating film is formed on the surface of the electromagnetic steel sheet.

This insulation film is intended to improve the iron loss by applying tension to the base steel sheet, to prevent slippage when processing the steel sheet to make motor parts and transformer parts, and to generate rust on the parts in use. Improvement of corrosion resistance to suppress it is also expected as one of the effects.
In order to share these purposes, it is common practice to form a plurality of different types of films. For these purposes, an oxide is often used as a material for forming this film. In particular, an oxide mainly composed of Si is often used to satisfy the above characteristics and cost.

  However, the oxide-based coatings that have been put to practical use until now are difficult to improve the adhesion to the base metal plate, which is a metal. Adhesion was ensured mainly as a mechanically joined state with a large uneven shape and a so-called anchor effect. However, the unevenness on the outermost surface of the base steel plate inhibits the movement of the domain wall that moves in the base steel plate during use of the steel plate, and thus causes a significant deterioration in magnetic properties.

  Therefore, in order to eliminate such damage, the interface between the steel sheet and the film is flat, and a film having an atmospheric sealing property is formed in advance between the tension-imparting film and the steel sheet, and the patent improves the adhesion by the action. A technique such as Document 2 is also disclosed. However, this technique has a drawback in that it is difficult to increase the tension applied to the mother steel sheet, and the effect of improving the magnetic properties due to the tension cannot be fully utilized.

  On the other hand, in the manufacture of iron cores, etc., after laminating electromagnetic steel sheets, they are fixed by welding, caulking, etc., but at that time, short circuit between the laminated steel sheets and generation of undesirable strain occur, It has been pointed out that it causes deterioration of the characteristics as a member.

Therefore, without using welding or the like, the organic material that melts at a high temperature contained in the film is used as an adhesive, and is fixed as a laminated member by heat treatment at a high temperature while the steel plates are stacked. Various techniques are also disclosed.
However, with this technology, the adhesive strength between steel plates is weak, and the adhesive strength is extremely high due to the temperature of the high temperature state where the member is exposed for various purposes in the process of manufacturing the member, and due to changes over time due to long-term use. Has been pointed out to cause problems.

JP-A-2-301571 JP-A-7-278833 JP 2000-12320 A

  An object of the present invention is to provide an electrical component comprising a magnetic steel sheet that achieves both improved adhesion of a coating that cannot be achieved by conventional methods and imparting tension to a base steel sheet, and a method for manufacturing the same. Is an issue.

The present invention preferably controls the structure and composition of an oxide film mainly formed on a base steel sheet of an electromagnetic steel sheet, and uses the electromagnetic steel sheet having such a film as a constituent member of an electrical component. Solve the problem.
The basic idea is to achieve compatibility of various properties by forming a multi-layered film formed on the base steel plate.

  That is, the adhesion between the film and the steel sheet mainly depends on the properties of the innermost layer of the film (the layer that is in contact with the mother steel sheet), and therefore the innermost layer is focused on the adhesion with the steel sheet, Ensure other characteristics in the layers other than the innermost layer. For example, the expression of tension is ensured in the intermediate layer, and further, slipperiness and insulation are ensured in the resurface layer, and the film structure is such that the steel sheet characteristics after the film is formed are optimally exhibited.

This invention based on such an idea solves the said subject by the following (1)-(20).
(1) An electrical component having a magnetic steel sheet processed into a predetermined shape as a constituent member, the magnetic steel sheet being in mass%, C: 0.07% or less (including 0), Si: 7.0% Or less (including 0), Mn: 6.5% or less (including 0), P: 0.30% or less (including 0), S: 0.080% or less (including 0), Al: 8. Multi-layer structure containing oxide on the surface of a base steel plate containing 0% or less (including 0), N: 0.070% or less (including 0), O: 0.070% or less (including 0) About one or two or more elements of Ni, Co, Cr, Cu, Mo, Nb, and Mn (concentration at the concentration site at the interface between the surface of the mother steel plate and the film) / (parent (Average concentration on the steel sheet surface) ≧ 2.0 and (concentration at the concentrated portion at the interface between the mother steel sheet surface and the film) / (the innermost layer of the film, ie, An average component in the layer in contact with the mother steel plate) ≧ 2.0.

(2) In the electrical component, the electromagnetic steel sheet is further enriched at the interface between the mother steel sheet and the film with respect to any one or more elements of Ni, Co, Cr, Cu, Mo, Nb, and Mn. The electrical component, wherein the concentration of the part is 0.10% by mass or more.
(3) In the electrical component, the electrical steel sheet further has an average depth of irregularities at the interface between the base steel sheet and the coating of 5.0 μm or less.
(4) In the electrical component, the electrical steel sheet further has an average period of irregularities at the interface between the base steel sheet and the coating of 15.0 μm or less.
(5) In the electrical component, the electrical steel sheet is further mass% in the innermost layer of the coating, Ni: 0.5% or more, Co: 0.5% or more, Cr: 0.5% or more, Cu An electrical component comprising 0.5% or more, Mo: 0.5% or more, Nb: 0.5% or more, and Mn: 0.5% or more.
(6) In the electrical component, the electromagnetic steel sheet further includes one or more elements of Ni, Co, Cr, Cu, Mo, Nb, and Mn (average concentration in the innermost layer of the coating). / (Average concentration in base steel plate)> 1.00 Electrical component characterized in that
(7) In the electrical component, the electromagnetic steel sheet may further include one or more elements of Ni, Co, Cr, Cu, Mo, Nb, Ti, B, and Mn (in the innermost layer of the coating). (Average concentration of) / (average concentration in a layer other than the innermost layer of the coating)> 2.
(8) In the electrical component, the electrical steel sheet further has a coating average of 30% by mass or more with respect to the SiO ₂ concentration of the coating, and (average concentration in a layer other than the innermost layer) / (in the innermost layer) Density)> 1.0 electrical component, characterized in that
(9) In the electrical component, the magnetic steel sheet further has an average thickness of an innermost layer of a film forming a multilayer structure of 10.0 μm or less and 1/2 of the total film thickness. An electrical component characterized by:
(10) In the electrical component, the electrical steel sheet further satisfies (thickness of the entire coating) / (steel plate thickness) ≦ 1/10.
(11) In the electrical component described above, the electrical steel sheet further has a tension generated in the steel sheet due to the film being 1 MPa or more.
(12) In the electrical component, the electromagnetic steel sheet further relates to the tension generated in the mother steel sheet due to the film and the thickness of each layer {[(tension due to the innermost layer) / (other than the innermost layer]. Tension caused by layer)] / (thickness of innermost layer)} × (thickness of layers other than innermost layer) <1.00.
(13) In the method of manufacturing an electrical component, a single layer of a substance or mixture mainly composed of oxide is applied to the surface of a mother steel sheet of an electromagnetic steel sheet, or a composition is formed by changing the composition of the substance or mixture. Then, heat treatment is performed at a temperature at which one or more oxides contained in the coating of the applied layer are melted, and the above coating and heat treatment are performed at least once. A method of manufacturing an electrical component, comprising: forming a film having a layered structure, and processing the electromagnetic steel sheet on which the film is formed into a predetermined shape.
(14) In the method for manufacturing the electrical component, after the base plate of the electromagnetic steel plate is processed into a predetermined shape, when the electrical component is manufactured using the processed base plate, the surface of the base plate is oxidized. A single layer of a substance or mixture mainly composed of an object is applied, or the composition of the substance or mixture is changed so as to form a multi-layer, and then one of oxides contained in the film of the applied layer. A method for producing an electrical component, characterized in that a coating having a multilayer structure is formed on the surface of a mother steel sheet by performing a heat treatment at a temperature at which the seed or two or more kinds are melted and performing the above coating and heat treatment at least once. .
(15) In the method of manufacturing the electrical component, a single layer of a substance or mixture mainly composed of oxide is applied to the surface of the base steel sheet of the electromagnetic steel sheet, or the composition of the substance or mixture is changed to form a multilayer. Then, heat treatment is performed at a temperature at which one or more oxides contained in the film of the applied layer are melted, and the above application and heat treatment are performed at least once. After forming a film on the surface of the steel sheet and processing the electromagnetic steel sheet on which the film is formed into a predetermined shape, when manufacturing electrical parts using the processed electromagnetic steel sheet, the surface of the electromagnetic steel sheet is again A method for producing an electrical component, wherein a coating having a multilayer structure is formed on the surface of a mother steel plate by performing coating and heat treatment at least once.
(16) In the method of manufacturing an electrical component, the heat treatment performed after the electromagnetic steel sheet is processed into a predetermined shape is performed by post-processing strain relief annealing.
(17) In the method for manufacturing the electrical component, the heat treatment for melting one or more of the oxides is performed by heating at a temperature range of 400 to 1200 ° C. for 0.1 to 3600 seconds. A method for manufacturing an electrical component.
(18) In the method of manufacturing an electrical component, a heat treatment for melting one or more oxides contained in a substance or mixture applied to the surface of the steel sheet is performed in an atmosphere with a dew point ≦ 0 ° C. A method for manufacturing an electrical component, characterized in that:
(19) In the method of manufacturing an electrical component, the substance or mixture for forming the surface film is applied by a dry process.
(20) In the electrical component manufacturing method, when performing heat treatment for melting one or more oxides in a layer of a substance or mixture mainly composed of oxide applied to the surface of the mother steel plate A method for producing an electrical component, which is performed in a state where a tension of 1 MPa or more is applied as stress acting on the surface of the mother steel plate.

  The electrical component of the present invention uses a magnetic steel sheet that has good film adhesion and has improved functions related to the film such as insulation and surface slipperiness. It is possible not only to stably obtain an electrical component such as, but also to obtain an electrical component with improved magnetic properties by stably generating a high tension on the steel sheet.

  More specifically, in the innermost layer film that is in contact with the base steel plate and needs to ensure adhesion, at least one of Ni, Co, Cr, Cu, Mo, Nb, and Mn is contained, and these elements are included in the film and the mother layer. By segregating at the interface with the steel sheet and forming the concentrated part unevenly distributed on the interface, the interface becomes very fine uneven and at the same time the chemical bond strength is improved, resulting in a coated steel sheet. An electrical steel sheet with improved adhesion can be obtained. At that time, the segregation of Ni, Co, Cr, Cu, Mo, Nb, and Mn can be efficiently performed by optimally controlling the substances added to the innermost layer film, the amount thereof, and the heat treatment applied to the film. You can get up.

In addition, the film formed on the innermost film is reduced not only by the elements necessary for ensuring adhesion, but also by reducing the content of the above elements, so that the insulation is not restricted. It is possible to apply insulation, slipperiness, or tension, which has not been achieved in the past, by making it easy to generate and slip or to generate tension.
The present invention can obtain an electrical component with improved magnetic properties without using a steel sheet short circuit even when used for a long period of time by using such an electromagnetic steel sheet.

Hereinafter, the present invention will be described in detail. In particular, an electromagnetic steel sheet used as a constituent member of the electrical component of the present invention will be described.
(A) About composition of base steel plate First, the composition of the base steel plate of an electromagnetic steel plate is demonstrated. In addition, content of each component element is the mass%.

  Since C deteriorates iron loss, it was limited to 0.07% or less. Preferably it is 0.025% or less. Further, it effectively works for texture improvement, suppresses the development of {111} orientation which is undesirable for magnetism, and has the effect of promoting the development of preferred {110}, {100}, {114} and other orientations. From this viewpoint, preferably 0.0031 to 0.0301%, more preferably 0.0051 to 0.0221%, more preferably 0.0071 to 0.0181%, and still more preferably 0.0081 to 0.0151%. It is.

  Generally, C is reduced to 0.0050% or less by decarburization annealing after cold rolling. From the viewpoint of production cost, it is possible to reduce the amount of C by degassing equipment at the molten steel stage, and if it is 0.0040% or less, the effect of suppressing magnetic aging is remarkable. Furthermore, coarse carbides are present in the steel plate, which is present on the surface of the base steel plate, and reacts with oxides in the coating during the heat treatment after coating, so that C is gasified and voids (bubbles, bubbles) are formed in the coating. It may form and significantly degrade the function of the coating. For this reason, it is more preferable to set it as 0.0030% or less, and 0.0015% or less is still more preferable. It may be 0%.

  Si increases the specific resistance of steel to reduce eddy currents and lower iron loss, but the effect is small when the addition amount is less than 0.2%. With low Si steel, there is almost no embrittlement of the steel and the magnetic flux density can be increased. However, considering the effect of reducing eddy current loss due to solid solution elements such as Si particularly in high frequency applications, preferably steel containing Si is preferably 1.0% or more, more preferably 2.0% or more. To do. However, if it exceeds 7.0%, the steel is embrittled and the magnetic flux density of the product is further reduced, so the content is made 7.0% or less. Preferably it is 5.5% or less, More preferably, it is 4.5% or less.

  Mn is an important element when using MnS or MnSe as an inhibitor and utilizing secondary recrystallization to improve magnetic properties. Like M, it increases the specific resistance of steel and reduces eddy currents, resulting in iron loss. It also has the effect of lowering. However, excessive addition reduces the magnetic flux density, so the upper limit is made 6.5%. Preferably it is 0.05 to 3.5%.

  If P exceeds 0.30%, embrittlement is severe, and it becomes difficult to perform hot rolling and cold rolling on an industrial scale, so the upper limit is made 0.30%. Preferably it is 0.10% or less.

  S is an element to be contained in the steel that uses sulfide as an inhibitor during secondary recrystallization. On the other hand, when secondary recrystallization is not used, magnetic characteristics, particularly iron loss, may be deteriorated. Further, as in C, coarse sulfide exists in the steel plate, and this exists on the surface of the base steel plate. When it reacts with the oxide in the coating during the heat treatment after coating, S is gasified and voids ( In some cases, the function of the film is significantly deteriorated. The S content is preferably as low as possible and may be 0%. In the present invention, the upper limit is 0.080%. Preferably it is 0.030% or less, More preferably, it is 0.010% or less, More preferably, it is 0.0030% or less, More preferably, it is 0.0010% or less.

  Al is usually added as a deoxidizing agent, but it is also possible to suppress the addition of Al and deoxidize with Si. Moreover, it has the effect which raises the electrical resistance of a steel plate as solute Al, and reduces an iron loss. In electrical steel sheets utilizing secondary recrystallization, AlN as an inhibitor plays a very important role. If it exceeds 8.0%, embrittlement becomes a problem, so the upper limit is made 8.0%. The upper limit is preferably 6.0%, more preferably 5.0%, still more preferably 4.0%, and even more preferably 3.0%. The lower limit may be 0, but unavoidably 0.0001% or more is often contained. In consideration of castability improvement by deoxidation and magnetic characteristics, it is preferably 0.01% or more, more preferably 0.08%, further preferably 0.5%, and further preferably 1.0%.

  N, as well as Al, AlN as an inhibitor has a very important role in conventional magnetic steel sheets utilizing secondary recrystallization. N, like C, degrades the magnetic properties, so it is set to 0.070% or less. Preferably it is 0.0301% or less, More preferably, it is 0.0221% or less, More preferably, it is 0.0181% or less, More preferably, it is 0.0151% or less. However, when Al is contained in an amount of about 0.010% or more, if a large amount of N is contained, it is preferable to avoid it because a large amount of fine nitride is formed and the magnetic properties are remarkably deteriorated.

On the other hand, when coarse nitrides are present in the steel plate and this is present on the surface of the base steel plate, as with C, it reacts with the oxides in the coating during the heat treatment after coating, and N is gasified into the coating. In some cases, voids (bubbles) are formed, and the function of the film is significantly deteriorated.
Considering the cost of denitrification of the steel sheet in the production process in order to avoid such nitride damage, it is preferable to reduce the N content in the molten steel stage in the Al deoxidized steel. In the present invention, it is preferably as low as possible, and if it is 0.0027% or less, the effect of suppressing property deterioration due to magnetic aging and nitride formation is remarkable, more preferably 0.0022%, and even more preferably. It is 0.0015% or less, and may be 0%.

  O forms inclusions in the steel and degrades the magnetic properties, and depending on the application, it may be a starting point for destruction during use. Moreover, in order to deteriorate the castability at the time of casting at the time of steel plate manufacture, it is preferable that it is low. The upper limit is 0.070%, preferably 0.030%, more preferably 0.010%, further preferably 0.005%, more preferably 0.003%, and may be 0%.

In addition to the above, the base steel sheet of the electrical steel sheet used in the present invention is added to control various properties in the conventional electrical steel sheet, Bi, Sn, Sb, REM, Ca, Mg, B, Cu, Ni, Even if elements such as Nb and Ti are added, the effect of the present invention is not impaired. In the present invention, as long as the content range of the above elements is satisfied, a steel plate generally known for an electromagnetic steel plate can be used.
The characteristics of the electrical steel sheet used in the present invention are not in the base steel sheet itself but in the state of the coating structure and the interface between the coating and the base steel sheet as described below.

(B) Film structure First, the film structure which is the greatest feature of the electrical steel sheet used in the present invention will be described.
The electrical steel sheet used in the present invention assumes a film mainly composed of oxide as will be described later, but the film essentially separates the functions required for the film and is optimal for each. In order to get a solution, it needs to be a multilayer structure.

As will be described later, in the electrical steel sheet used in the present invention, a specific element concentrated at the interface between the film and the base steel plate plays an important role, although this element is very useful at the above interface. When dispersed throughout the coating, there are not only factors that hinder the properties of the coating itself, but also the addition cost is a heavy burden because it is generally an expensive element. Of course, the single-layer coating also has the advantage that the coating process can be simplified. However, the multilayer coating has a characteristic effect that more than compensates for its disadvantages. In other words, the innermost layer in contact with the base steel sheet should be specialized for adhesion to the steel sheet, and insulation, slipperiness, tension imparting to the steel sheet, etc. should be obtained with the outer layer film having the best characteristics. Yes.
In the present invention, an electrical steel sheet having a film structure of at least two layers or three layers or more is used.

(C) State of Interface between Film and Base Steel Plate Next, the state of the interface between the film and the base steel plate, which is another feature, will be described.
The element that exists at the interface and expresses the characteristics of the electrical steel sheet used in the present invention is referred to as a “specific element”. Hereinafter, the “specific element” is referred to as “Ni, Co, Cr, Cu” in this specification. , Mo, Nb, or Mn.

(C-1) Concentration of specific element In the electrical steel sheet used in the present invention, the characteristics are improved by forming a concentrated part of the specific element at the interface between the base steel sheet and the coating. Although this mechanism is not necessarily clear, the reactivity of the base steel plate and the oxide in the film is different at the concentrated and non-concentrated sites of the specific element, which makes the interface a fine uneven shape, or It is thought that these concentrated elements have the effect of strengthening the chemical bond between the substance in the film and Fe in the mother steel plate.
In particular, the latter chemical bond becomes prominent when a large amount of oxide is contained in the film. Therefore, the oxide in the film and Fe in the base steel sheet are combined with oxygen in the film. It is considered that the chemical bonding state with the Fe oxide is changed.

Phenomenologically, this effect becomes significant when the specific element has a portion that is concentrated at the interface between the base steel sheet and the film in excess of the respective average concentrations of the base steel sheet and the film. It is possible to characterize as follows.
For the specific element, (concentration at the concentration site at the interface between the base steel plate and the film) / (average concentration at the base steel plate) ≧ 2.0 and (concentration at the concentration site at the interface between the base steel plate and the film) / ( It is preferred that the average concentration in the innermost layer of the coating is ≧ 2.0. More preferably, each is 3.0 or more, more preferably 5.0 or more, more preferably 10.0 or more, and if there is a portion concentrated to 50.0 or more, the characteristics are remarkably improved. The chemical site may be a pure element.

The above-described concentration can be sufficiently observed with the latest analysis equipment such as an electron microscope, X-ray analysis, electron beam analysis, and ion analysis. Of course, identification is possible by other methods such as chemical analysis.
Needless to say, when examining the measurement data, it is necessary to determine the concentration of the specific element in consideration of not only the area of the measurement region but also the depth of the measurement region when analyzing from a specific surface.
For example, when a region of 100% of a specific element is formed on a specific surface but it is very thin, if a component analysis is performed with an analytical instrument using an electron beam or X-ray from the surface, the film is This is a case where a low quantitative value is obtained as the content of the specific element because the components in the region including the base material portion are detected.

  In the present invention, analysis limited to a spatially sufficiently small region is necessary. Of course, even in a quantitative value obtained by averaging a wide region including a region where the specific element is not concentrated as in the above example, the quantitative value defined in the present invention, for example, the concentration of the specific element is 2 of the average content in steel. If it satisfies .0 times or more, it is not a problem to adopt the data.

  The effect of the invention becomes significant when the concentration of the specific element at the concentrated portion of the specific element formed at the interface between the mother steel plate and the coating is 0.10% or more. Preferably it is 0.5% or more, more preferably 1.0% or more, more preferably 3.0% or more, more preferably 10.0% or more, more preferably 30.0% or more, more preferably 50.0. % Or more, more preferably 70.0% or more, and even if a region having a concentration of 100% is formed, the effect of the invention is not impaired.

  It should be noted that the density of the micro area is sensitively influenced by the size of the measurement area. In other words, if one atom is measured as a sufficiently small region and limit, a space with a concentration of 100% will exist in any case. Of course, such a thing is excluded from the thickening part prescribed | regulated by this invention. In other words, if a too wide area is measured, the presence of a minute thickened portion may be overlooked. As a measure of the measurement region, although it is related to the size of the interface unevenness described later, it is preferable to use a region having a spread of about 0.1 μm. Of course, as long as it is recognized that the values obtained in the region below this are representative of the overall characteristics, it may be used depending on the measuring instrument and method.

  In the electrical steel sheet used in the present invention, as described above, the purpose is to regulate the concentration of specific elements at the interface between the base steel sheet and the film by defining the components of the base steel sheet and the components of the film and the substances forming the film. Among these properties, the adhesion of the film can be remarkably improved.

(C-2) Interfacial depth and average period of interface As mentioned above, the mechanism for improving the adhesion of the film is not necessarily elucidated, but the microscopic unevenness at the interface changes. Can be characterized. This unevenness is characterized by a very fine and dense state as compared with the form of the interface between the base steel plate and the coating of a normal electromagnetic steel plate. As one of the characteristics, the depth of the unevenness at the interface is defined.

  In the electrical steel sheet used in the present invention, the uneven average depth is 5.0 μm or less. It is possible to observe very fine unevenness by observing finely, but the depth of the unevenness is such that the cross section of the steel sheet can be observed with a SEM (scanning electron microscope) and observed at a magnification of 2000 times. Shall be measured. Small unevenness of 0.5 mm or less in a 2000 times photograph is excluded because it causes a problem in measurement accuracy. That is, unevenness of 0.25 μm or less is ignored.

  This does not mean that the unevenness below this does not affect the adhesion, and is merely a rule on the measurement method. It is preferable for the present invention that the adhesion is improved by fine irregularities below this, and it is rather preferable that such a state is achieved. The unevenness depth thus measured is preferably 3.0 μm or less, more preferably 2.0 μm or less, further preferably 1.0 μm or less, and further preferably 0.5 μm or less. The lower limit is not particularly required and may be 0 μm.

  Adhesion is improved by forming a large number of such irregularities, and the average period of irregularities is 15.0 μm or less, that is, 100 or more irregularities exist as a set in a length of 1 mm. The effect is remarkably good. More preferably, the average period is 10.0 μm or less, more preferably 5.0 μm or less, more preferably 3.0 μm or less, further preferably 1.0 μm or less, more preferably 0.5 μm or less, and further preferably 0.2 μm. It is as follows. Although there is no particular need to provide a lower limit, in terms of the measurement method, irregularities with a depth of 0.25 μm or less are ignored, so the period is at most 0.05 μm.

As described above, in the electrical steel sheet used in the present invention, the roughness of the interface between the film and the base steel sheet is specified, but this also applies to the steel sheet roughness before forming the film and before applying the film forming substance. It will be affected.
However, the electrical steel sheet used in the present invention does not particularly define the roughness of the base steel sheet. This is because controlling the roughness within the above range after film formation is a decisive factor for the characteristics.

  The roughness of the interface controlled within the above range shows a finer form than the generally controlled surface roughness of the steel sheet. From the final characteristics, it is preferable to keep the roughness of the base steel sheet as small as possible. If the roughness of the base steel sheet is too rough, there will be rough unevenness along with fine unevenness at the interface, which deteriorates the properties of the steel sheet and causes film defects. The surface roughness of the mother steel plate is generally sufficient, but as a guideline, Ra is 5 μm or less, preferably 3 μm or less, more preferably 1 μm or less, more preferably 0.5 μm or less, and further 0.2 μm. In the following, smoothing as a general steel sheet surface is rather preferable from the characteristics of the steel sheet.

(C-3) Containing method and content of specific element The specific element can be concentrated at the interface by adding it to the film side or the base steel plate side, and the method itself is particularly limited. It is not a thing. However, if added to the base steel plate side, it may undesirably affect the magnetic properties of the base steel plate. Moreover, it cannot be said that it is advantageous to disperse an element that should be unevenly distributed in a very narrow range called an interface in a steel plate that is much thicker than the coating. Furthermore, considering the movement for segregation of the specific element at the interface, it is advantageous to include the specific element on the film side where a part of the film is melted by heat treatment or the like and can be expected to have higher fluidity than the steel sheet. It becomes. Furthermore, as described above, since the electrical steel sheet used in the present invention relies heavily on the innermost layer of the film to ensure the adhesion of the film, the specific element is preferably contained in the innermost layer of the film.
Therefore, for the specific element, it is preferable that (average concentration in the innermost layer of the coating) / (average concentration in the base steel plate)> 1.00.

In the electrical steel sheet used in the present invention, one of the characteristics is that a large amount of a specific element is contained in the innermost layer of the coating, that is, the layer in contact with the base steel sheet. In this case, the content (mass%) Described below.
Among the specific elements, Ni and Co are particularly important elements with extremely remarkable effects. First, these will be described.

  If the Ni content is less than 0.5%, there is no beneficial effect to make the film multi-layered. In order to obtain a sufficient effect, addition of 0.80% or more is preferable, and when 1.0% or more and 2.0% or more are added, a remarkable effect is obtained. When 5.0% or more is added, the effect tends to be saturated. Excessive addition is not preferable from the viewpoint of cost, but at the same time, the non-uniformity of the reaction between the film and the steel becomes large, and it becomes easy to cause film defects and it is difficult to apply tension. It is preferable. More preferably, it is 10.0% or less, and even if it is 8.0% or less, a sufficient effect can be obtained.

  Since Co has a remarkable effect like Ni, it can be added in the present invention. If it is less than 0.5%, there is no beneficial effect to make the film multi-layered. In order to obtain a sufficient effect, addition of 0.80% or more is preferable, and when 1.0% or more and 2.0% or more are added, a remarkable effect is obtained. When 5.0% or more is added, the effect tends to be saturated. Excessive addition is not preferable from the viewpoint of cost, but at the same time, the non-uniformity of the reaction between the film and the steel becomes large, and it becomes easy to cause film defects and it is difficult to apply tension. It is preferable. More preferably, it is 10.0% or less, and even if it is 8.0% or less, a sufficient effect can be obtained.

  Since Cr has the same effect as Ni and Co, it can be added in the present invention. If it is less than 0.5%, there is no beneficial effect to make the film multi-layered. In order to obtain a sufficient effect, addition of 0.80% or more is preferable, and when 1.0% or more and 2.0% or more are added, a remarkable effect is obtained. When 5.0% or more is added, the effect tends to be saturated. Excessive addition is not preferable from the viewpoint of cost, but at the same time, the non-uniformity of the reaction between the film and the steel becomes large, and it becomes easy to cause film defects and it is difficult to apply tension. It is preferable. More preferably, it is 10.0% or less, and even if it is 8.0% or less, a sufficient effect can be obtained.

  Next, Cu and Mo, which are elements having a specific action among the specific elements and exhibiting remarkable effects on the effects of the invention, will be described.

  Cu exhibits the same effect as Ni and Co, but Cu alone has a relatively small effect, and the effect becomes remarkable when added simultaneously with other elements, particularly Ni and Co. If the content is less than 0.5%, there is no beneficial effect to make the film multi-layered. In order to obtain a sufficient effect, addition of 0.80% or more is preferable, and when 1.0% or more is added, a remarkable effect is obtained. If the addition is 2.0% or more, the effect tends to be saturated. Excessive addition is not preferable from the viewpoint of alloy cost, but at the same time, the non-uniform reaction between the film and steel becomes large, and defects tend to occur in the film. More preferably, it is 5.0% or less, and even if it is 3.0% or less, a sufficient effect can be obtained.

  The mechanism by which Cu becomes effective when combined with Ni or Co is not clear, but Cu does not induce changes in the interface shape directly like Ni and Co, but increases the effect of Ni and Co. It is thought that For example, it is considered that when Ni or Co segregates at the interface between the coating and the base steel plate, the segregation behavior, particularly the amount of segregation and the distribution of uneven distribution on the interface is affected. Cu is unlikely to form an oxide, and Cu in the film is considered to be relatively easily segregated at the interface, and it is also considered that the segregation of Cu affects the segregation of Ni and Co. Although it is not clear whether Ni or Co preferentially segregates in the Cu segregation part, or avoiding the Cu segregation part, the segregation of Ni or Co becomes a preferable form, but some interaction is exerted at the interface part. It is thought that there is.

  Mo has an intermediate effect between Ni and Co and Cu. That is, it has an effect of making the effects of Ni and Co not only remarkable, but also has a large effect alone. Below 0.5%, little beneficial effect is detected. In order to obtain a beneficial effect, addition of 0.8% or more is preferable, and when 1.0% or more and 2.0% or more are added, a remarkable effect is obtained. When 5.0% or more is added, the effect tends to be saturated. Excessive addition is not preferable from the viewpoint of cost, but at the same time, the non-uniformity of the reaction between the film and the steel becomes large, and it becomes easy to cause film defects and it is difficult to apply tension. It is preferable. More preferably, it is 10.0% or less, and even if it is 8.0% or less, a sufficient effect can be obtained.

  The effect of Mo is not clear, but in addition to the effect of Cu, it may form a complex oxide with oxygen in the film together with Ni and Co, which may affect the behavior of Ni and Co. This is probably because the interaction with Ni and Co attracts strongly and exists in such a form that these segregated portions are also dissolved.

Other specific elements include Nb and Mn. These elements are not effective by themselves, but rather have the effect of increasing the effects of the above-described Ni, Co, Cr, Cu, and Mo.
Although this mechanism is not clear, these form oxides in the film, and the above elements are rejected and segregated on the steel sheet side, or combined with C, N, S, etc. contained in the steel sheet in a small amount. Then, it is considered that a compound is formed on the surface of the steel plate and becomes a segregation starting point of Ni or the like.

  In order to obtain this effect, Nb is contained in an amount of 0.5% or more, preferably 0.8% or more, and more preferably 1.0% or more. In the case of Mn, 0.5% or more, preferably 1.0% or more, more preferably 3.0% or more. However, if these elements are contained excessively, defects are likely to occur in the film, and the insulating properties, slip properties, corrosion resistance, adhesion, etc. that the film should have are deteriorated. For this reason, Nb is preferably 20.0% or less, more preferably 10.0% or less, and still more preferably 5.0% or less. Mn is preferably 20.0% or less, more preferably 10.0% or less, and still more preferably 7.0% or less.

(C-4) Containment of specific elements in the substance or mixture to be coated The content of the 7 elements described above is the content of the elements in the film formed on the mother steel plate in the final use situation. Although in terms of quantity, a similar range can be defined for substances or mixtures applied to the surface of the mother steel plate to form a film.

  The element content in the film and the element content in the applied substance or mixture are externally determined in the treatment process associated with the film formation, typically a heat treatment in which part or all of the applied substance or mixture is melted and solidified. It will be the same if there is no movement of material.

However, depending on the type of coating substance or mixture and the film forming treatment conditions, the balance of the substance with the outside of the substance occurs. For example, when the nitride in the coating material reacts with the oxide in the coating material or oxygen in the atmosphere to generate oxide, nitrogen is gasified and diffused into the atmosphere, or Fe from the mother steel plate For example, when it spreads and enters. At this time, the content of the element in the film is different from that of the substance or mixture applied to the surface of the mother steel plate to form the film.
And since the change is influenced also by heat processing conditions, it cannot be determined uniquely. From the viewpoint of control, it is easier from the viewpoint of industrial production to control with a material to be applied in advance than a material in the final film.

For this reason, in the electrical steel sheet used in the present invention, the content of the seven elements that are essential for the effects of the present invention is not only in the film, but also in the substance or mixture applied to the surface of the mother steel sheet in order to form the film. Can be defined. The range is the same as that in the film.
As described above, since the change in content is influenced by heat treatment conditions and the like, it is difficult to determine uniquely, but if it is a person skilled in the art who manufactures steel materials by controlling the substance reaction, it can be applied. Once the materials and processing conditions are determined, they can be adequately controlled after desk calculations and several trials.
Whether it is the content in the film or the content in the substance or mixture applied to the mother steel plate surface to form the film, the segregation of the specific element at the interface is within the scope of the present invention. It is possible to get enough effects to get up and aim.

(C-5) Concentration of specific element in the film The characteristics of the electrical steel sheet used in the present invention are preferable in terms of functionality and cost by considering a number of functions required for the film and making it into multiple layers. Is to be. For example, the layer in contact with the mother steel plate has a composition with good adhesion to the steel plate, the tension is secured in the intermediate layer, and the outermost layer is a film with good slip and insulation properties. Of these, it is particularly important to secure adhesion to the steel sheet at the innermost layer of the coating film forming the multilayer structure and to suppress defects such as coating peeling.
Hereinafter, the features of the electrical steel sheet used in the present invention with the innermost layer differentiated from other layers will be described.

  The effect of the electrical steel sheet used in the present invention becomes significant when a specific element is preferentially added to the innermost layer of the film, that is, the layer in contact with the mother steel sheet. It is preferable that (average concentration) / (average concentration in a layer other than the innermost layer of the film)> 2. More preferably, it is 5 or more, more preferably 10 or more, more preferably 50 or more, more preferably 100 or more, and it goes without saying that there is no problem even if the content of layers other than the innermost layer is 0. In addition, the form of the substance when adding a specific element to the film is considered various. It is conceivable to add it as a pure metal or as an intermetallic compound or non-intermetallic compound, and an oxide is one of preferred forms as described later, but is not particularly limited. The change in the interface as described above occurs mainly due to the reaction during the heat treatment applied after coating.

(D) Other More Preferred Forms of Film in Electrical Steel Sheet Used in the Present Invention As described above, the electrical steel sheet used in the present invention is characterized by the film structure and the state of the interface between the film and the base steel sheet. However, the film | membrane used as the premise and the more preferable film | membrane form are further demonstrated below. The following description is common to the innermost layer and the other layers.

(D-1) About the substance which comprises a membrane | film | coat The membrane | film | coat in the electromagnetic steel plate used by this invention generically says the film | membrane currently formed in the surface of a steel plate. However, a film similar to metal plating in which 50% or more of the film becomes a metal phase by volume ratio is excluded.
As a substance constituting the film, any compound such as oxide, carbide, nitride, sulfide, fluoride, chloride, hydroxide, nitrate, sulfate and the like can be contained. Further, the inclusions in the film include not only substances intentionally added, but also those produced by a reaction during the treatment for forming the film.

  The method for causing the constituent material of the film to be present on the steel sheet surface is not particularly limited, and can be achieved by generally known surface treatments such as vapor deposition, plasma spraying, coating, oxidation, and nitriding.

  From the viewpoint of the effect, it is preferable that the film is mainly composed of an oxide. The effect of the invention becomes remarkable when 70% or more of the composition of the substance constituting the film is an oxide. Preferably, it is 80% or more, more preferably 90% or more, more preferably 95% or more. By making 99% or more an oxide, the effect of the invention becomes more remarkable, and it may be 100%. However, it is generally assumed that it can be contained in substances mainly composed of oxides such as various glasses.

  Note that, in a conventional electromagnetic steel sheet, as a known technique, a film mainly composed of oxides such as oxides of Si, Mg, Al, Ti, Cr, or composite oxides thereof is formed. A preferred embodiment of the present invention is a film mainly composed of oxides, but is completely different from the prior art in terms of the film structure including the interface, manufacturing method, characteristic improvement effect, characteristic improvement mechanism (technical idea), and the like. Is.

Considering not only the characteristics as a film but also the cost and productivity of raw materials, the ease of processing, etc., the oxide in the film is practically composed mainly of SiO ₂ . It is preferable to set it as 30% or more by the mass% in a film. It is more preferable to set it to 45%, and it may be 60% or more, further 75% or more, and further 90% or more. However, increasing SiO ₂ also means that the content of the specific element is reduced. It is necessary to keep the inner layer within an appropriate range.

In the electrical steel sheet used in the present invention, it is preferable to increase the SiO ₂ concentration preferentially in a layer other than the innermost layer over the innermost layer, (average concentration in a layer other than the innermost layer) / (average in the innermost layer) Density)> 1.0. More preferably, it is 1.2 or more, and the layer other than the innermost layer may be made of SiO ₂ 100%. In the electromagnetic steel sheet used in the present invention, the adhesion between the film and the steel sheet is ensured in the innermost layer, and therefore, a 100% SiO ₂ film that hardly adheres normally to the steel sheet can be formed on the steel sheet surface.

In addition, when other oxides are used, it is possible to limit the main oxides to several oxides, including workability and cost, and also the case where the above specific elements are added. That is, it is preferable that the composition of the film includes one or more of NiO, CoO, Cr ₂ O ₃ , NbO ₂ , Nb ₂ O ₅ , and MnO. Examples of the auxiliary oxide include Na ₂ O, K ₂ O, MgO, ZnO, Al ₂ O ₃ , Sb ₂ O ₅ , P ₂ O ₅ , SnO ₂ , ZrO ₂ , TiO ₂ , and B ₂ O _3. ,and so on. Of course, the inclusion of oxides not shown here does not impair the effects of the present invention.

(D-2) Form of film Next, the form of the film will be described.
If the film is too thick, when it is laminated to form an electrical component such as an iron core of a transformer, the abundance of the steel sheet that bears the magnetic properties, the so-called space factor, decreases, and the magnetic properties as a member are impaired. End up. In this respect, it is preferable that the film is thin, but a certain thickness is required in order to exert a great steel plate tension on the film defect suppression and magnetic properties. In the electromagnetic steel sheet used in the present invention, the innermost layer that needs to contain a relatively large amount of a specific element in order to ensure close contact with the steel sheet is controlled to be relatively thin, and the innermost layer for securing the steel sheet tension, slipperiness, etc. The layers other than the inner layer are controlled to be relatively thick.

  That is, the average thickness of the innermost layer of the film forming the multilayer structure, that is, the layer in contact with the mother steel plate is 10.0 μm or less and may be 1/2 or less of the total film thickness. preferable. The thickness of the innermost layer is more preferably 5.0 μm or less, and further preferably 3.0 μm or less. When there is no film to be called the innermost layer, it is not included in the present invention, but even if the thickness is 1.0 μm or less, further 0.5 μm or less, and further 0.1 μm or less, the effect of the present invention Is detectable. The ratio of the innermost layer thickness to the total film thickness is preferably 1/3 or less, more preferably 1/5 or less, further preferably 1/10 or less, and more preferably 1/20 or less. The space factor is related to the thickness of the mother steel plate. In the present invention, it is preferable that (average thickness of all coatings) / (steel plate thickness) ≦ 1/10. Further, it is 1/20 or less, further 1/40 or less, and may be 1/100 or less.

The coating basically forms the same material with the same thickness on both the front and back surfaces of the steel sheet, but is not limited to this. Depending on the method of use and application, a film within the scope of the present invention may be formed with different materials or different thicknesses on the front and back sides.
Moreover, it is also possible to impart various surface characteristics by forming organic substances such as epoxy resin, phenol resin, and acrylic resin on a film mainly composed of oxide as in the case of conventional electromagnetic steel sheets. There is no loss.

(D-3) About the tension | tensile_strength of a film | membrane In the electromagnetic steel plate used by this invention, it is one of the characteristics that the tension | tensile_strength which arises in a mother steel plate is 1 Mpa or more. Preferably it is 3 MPa or more, more preferably 5 MPa or more, more preferably 10 MPa or more, more preferably 15 MPa or more, more preferably 20 MPa or more, more preferably 30 MPa or more, and even if a larger tension is applied, there is no problem. .

  As is generally well known, such steel plate tension is caused by the difference between (linear expansion coefficient of the coating) and (linear expansion coefficient of the base steel plate), and the linear expansion coefficient of the coating is less than that of the base steel plate. By making it small, tension is generated in the steel sheet during the cooling process after the heat treatment. Basically, the tension that contributes to the magnetic properties is controlled by the difference in expansion coefficient, the film thickness, and the heat treatment conditions such as the heat treatment temperature and the cooling rate. The larger the difference in the expansion coefficient, the greater the tension that can be applied to the steel sheet. However, the compressive force acts on the film in the in-plane direction of the steel sheet. Care must be taken because the coating will be destroyed and defects will be generated.

  The electrical steel sheet used in the present invention has a feature that it is very strong against breakage due to such compressive force because the adhesion between the oxide film and the base steel sheet is very high. When the tension described here does not occur, not only the magnetic properties of the steel sheet deteriorate, but also the film tends to break down, and the film characteristic of the present invention has defects due to slight impact and deformation during steel sheet handling and use. As a result, the adhesiveness is lowered and the insulating property and the slip property are also adversely affected.

  Further, in the electrical steel sheet used in the present invention, regarding the tension generated in the mother steel sheet due to the film and the thickness of each layer, {[(tension caused by the innermost layer) / (caused by layers other than the innermost layer] Tension)] / (thickness of innermost layer)} × (thickness of layers other than innermost layer) <1.00. This also aims to secure the tension generated in the base steel plate in the entire coating as much as possible by a layer separated from the base steel plate.

  That is, when a large tension is generated in the base steel plate by the coating layer in contact with the base steel plate, a large compressive force acts on the coating layer, and the coating layer is likely to be broken. In order to avoid this, it is effective to reduce the rate of change of stress near the interface between the base steel plate and the coating as much as possible. For this reason, {[(tension caused by the innermost layer) / (because of layers other than the innermost layer) Tension)] / (thickness of innermost layer)} × (thickness of layers other than innermost layer) <1.00. More preferably, it is 0.95 or less, More preferably, it is 0.90 or less, More preferably, it is 0.80 or less, More preferably, it is 0.60 or less.

(E) About the manufacturing method of the electrical component of this invention (E-1) About the formation method of a film | membrane Hereafter, the formation method of the steel plate film in the manufacturing method of the electrical component of this invention is described.
It goes without saying that the film forming method is not limited to the method shown here, but according to this method, the effect of the invention can be obtained efficiently and at low cost. However, the electrical steel sheet used in the present invention needs to form a segregation part of a specific element at the interface, and further control the reaction between the film constituent material and the base steel sheet. In that sense, the purpose is simple and uniform surface treatment. It is generally difficult to achieve.

  One method of forming a coating on an electrical steel sheet used in the present invention is to apply a suitable amount of a substance or mixture containing a specific element on the surface of the mother steel sheet, and then form the film by treating at a high temperature and then a specific element. It is intended to cause segregation at the interface and reaction between the film and the base steel plate.

  A typical example of this method is to apply an oxide or a substance containing an oxide to a steel sheet, and then at a temperature higher than the temperature at which one or more of the oxides contained in the applied film are melted. It is formed by heat treatment and then solidifying. During this heat treatment, segregation at the interface of specific elements, accompanying change in interface morphology, densification of the film, generation of thermal strain, change in film surface properties, etc., insulation, adhesion, slipperiness, corrosion resistance, Tension and the like are in a preferable state.

Next, means for forming a multi-layered film and its procedure will be described.
It is possible to repeat the coating-heat treatment (melting) -solidification process one layer at a time, but considering the manufacturing cost, the coating is first applied to the required multilayer, then heat-treated, More preferably, the multilayer is melted and solidified at once. Of course, a method of solidifying one layer and a method of solidifying multiple layers at a time may be combined. In that case, the layer that forms the interface with the surface of the mother steel plate is preferably formed by a method of solidifying one layer, and the other layers are formed by a method of solidifying a plurality of layers at once.

  In addition, the application of the substance containing an oxide is preferably performed by a dry process from the viewpoints of manufacturing cost, disposal of waste accompanying the application, and the like. Furthermore, by using a dry process, it is possible to suppress the occurrence of film defects due to gas atoms from the atmosphere as described later, the film uniformity is improved, and the effect of improving the steel sheet characteristics is also favorable. For the application by the dry process, it is usually possible to use electrostatic powder coating or the like that has a proven record in various coatings.

  It is advantageous in terms of production efficiency that the step of forming the multi-layered film on the steel plate as described above is performed at the end of the manufacturing process of the base steel plate before the steel plate is processed into an electrical component. However, the present invention is not limited to such a method. Part or all of the multi-layered film can be formed during the process of processing the electrical steel sheet into an electrical component.

  That is, at least one layer including the innermost layer of the multi-layered film is formed in the manufacturing process of the mother steel plate, and one or more remaining layers formed on the upper layer process the steel plate into an electrical component. You may form in a process, and you may form all the films of a multilayer structure in the process of processing the steel plate into an electrical component using the electromagnetic steel plate in which the film is not formed.

For example, when a laminated iron core is manufactured, the film-forming substance can be applied before lamination of steel plates in the course of processing, and the film-forming heat treatment can be carried out after lamination of the steel plates.
In addition, after punching the steel sheet into a predetermined shape, the film forming material is applied to only one side of the steel sheet, and the coated surface is laminated so that the coated surface is in the same direction, and then heat treatment is performed, so that the film is formed and laminated. Can be simultaneously fixed. By doing in this way, the film formation process conventionally performed by the steel plate manufacture side is abbreviate | omitted, or using the technique currently disclosed by patent document 3, laminated steel plates, such as crimping and welding which were performed at the time of a process, are performed. It is also possible to omit the fixing process.

Furthermore, the energy cost can be reduced by utilizing strain relief annealing, which is generally performed when an electrical steel sheet is processed into a predetermined shape to manufacture an electrical component, as a film forming heat treatment.
When the laminated steel sheet is fixed in this way, according to the present invention, the adhesion between the film and the base steel sheet is strong, and it is possible to completely eliminate the trouble of peeling at the interface between the film and the base steel sheet as in the conventional method. Become. Of course, it is also possible to use a method in which a film is formed with a steel plate, only heat treatment is performed in a state of being laminated as a member, and the film is re-melted and solidified so as to fix the layer.

(E-2) Heat treatment conditions Next, heat treatment conditions for melting one or more oxides contained in the applied substance will be described.
If the heat treatment temperature is too low, the oxide will not be sufficiently melted and the film will not be densified or flattened, resulting in film defects and insufficient segregation of specific elements, resulting in poor adhesion. To do. If the temperature is too high, not only will there be a problem of energy costs, but the viscosity of the molten film material will decrease too much, making it difficult to ensure the thickness of the film, and the reaction between the oxide in the film and the base steel plate. Is too intense to make it difficult to form a good film including the interface structure and to inhibit the intended function. A suitable temperature range is 400 to 1200 ° C, preferably 500 to 1000 ° C, more preferably 600 to 900 ° C, and still more preferably 700 to 850 ° C.

  Similarly, the heat treatment time is also an important factor, preferably 0.1 to 3600 seconds, more preferably 0.2 to 1200 seconds, further preferably 0.5 to 300 seconds, and more preferably 1.0 to 60 seconds. is there. It goes without saying that the higher the heat treatment temperature, the shorter the time for holding at that temperature. If the time is too short, the time required for the concentration of specific elements at the interface and the formation of irregularities at the interface will be insufficient, and if it is too long, the diffusion of Fe from the mother steel sheet into the coating will be insufficient. The amount increases, and the properties of the film change to undesirable ones.

  Another feature of the multi-layer coating process in the present invention is the control of the dew point during the heat treatment for film formation. In this process, if heat treatment is performed in an atmosphere with a too high dew point, defects may occur in the film after the heat treatment. The cause of this is not clear, but gas atoms that have penetrated into the base steel plate during heat treatment are discharged from the base steel plate as the steel plate after heat treatment cools, causing bubbles to form in the film or at the interface, resulting in film defects. it is conceivable that. This gas atom may be generated not only from the atmosphere but also from the applied film-forming substance. For this reason, it is preferable that the substance containing an oxide to be applied to form a film does not contain organic substances that easily decompose or moisture. Control of the atmosphere makes the dew point 0 ° C. or less, and the effect of suppressing this damage becomes remarkable. It is preferably −10 ° C. or lower, more preferably −20 ° C. or lower, further preferably −40 ° C. or lower, and further preferably −60 ° C. or lower.

(E-3) About the tension | tensile_strength provision method As above-mentioned, it exists in the state which has produced the tension | tensile_strength in the mother steel plate as a characteristic of the electromagnetic steel plate used by this invention. This tension can be generated during the film formation heat treatment and its cooling due to the difference in thermal expansion between the film material and the base steel sheet, but in the present invention, the tension is applied to the steel sheet during the film formation heat treatment. In addition, it is possible to leave the tension in the mother steel plate by removing the tension after the film formation.

  However, in this method, anisotropy in the plate surface is generated in the remaining tension depending on how the tension is applied. This anisotropy does not cause any harm, and may be preferable depending on the application. The direction of tension can be controlled by the required characteristics and usage method. For example, in the case of manufacturing a steel sheet with a coil, by applying tension in the longitudinal direction of the coil, the tension in this direction increases and iron loss decreases, and a large compressive force acts on the film. Therefore, the fracture resistance of the film against the deformation in this direction is improved. In order to obtain this effect remarkably, it is preferable to apply a tension of 1 MPa or more. It goes without saying that the greater the tension, the greater the effect, but it is necessary to pay attention to the above-mentioned anisotropy, and when the tension is too high, the steel sheet deforms or the film itself breaks due to the compressive force generated in the film. Care must be taken because it is possible that this will happen.

(E-4) Production of base steel plate With respect to the base steel plate containing the above-mentioned components, it is melted in a converter in the same manner as a normal electromagnetic steel plate, is made into a slab by continuous casting, then hot rolled, pickled, cold Manufactured by processes such as rolling and annealing. Performing cold rolling and annealing a plurality of times in these steps, or passing through a decarburization step, does not impair the effects of the present invention. Moreover, there is no problem even if it is manufactured by a process such as a thin slab CC which omits the hot rolling process instead of the normal process.

  Examples of the present invention will be described below, but the conditions adopted in the examples are one example of conditions for confirming the feasibility and effects of the present invention, and the present invention is limited to this one example of conditions. It is not something. The present invention is defined only by the matters described in the claims of the claims, and various conditions can be adopted as long as the object of the present invention is achieved without departing from the present invention. .

  Various substances were applied to the base steel sheet of various electromagnetic steel sheets shown in Table 1, heat-treated to form a film, and the characteristics were evaluated. At this time, a specific substance is contained in the substance applied to the steel sheet surface, and segregation on the steel sheet surface is induced in the heat treatment to obtain the effect of the invention.

  As a material applied to the steel plate surface, a mixture mainly composed of oxides shown in Table 2 was used. The ratio of oxides and the like contained in the mixture is as shown in Table 2, and the inner layer was coated by adding an oxide or the like containing a specific element.

  As shown in Tables 3 and 5, the specific element is added in the form of oxide, pure metal powder, carbide, nitride, sulfide, etc., and the final concentration of the specific element is the value shown in Tables 3 and 5. The addition amount was adjusted so that For this reason, the ratio of oxides and the like in the final coating material deviates from the numbers in Table 2, assuming that the total is 100%. The film finally formed has the same quality and thickness on the front and back of the steel sheet.

Two coating methods were used. One is a method in which the coating substance is made into powder and is made to adhere to the surface of the steel sheet by being charged, which is generally known as electrostatic powder coating. Since this method does not use a liquid solvent or the like in the coating step, it is generally called a dry process, and is described as “Dry” in Tables 4 and 6.
The other method is to mix the powdered coating material with the liquid and spray it onto the steel plate. As the liquid, water, an organic solvent, or the like can be used, which is generally known as a wet process. In Tables 4 and 6, “Wet” is described. In this example, water is used as the liquid, and so-called “clay” such as silica, silica sand, borax, etc. is used as the base material in Table 2 in order to control the mixing of the coating substance in water and the adhesion to the steel plate. Minutes were added as some additive.

In this embodiment, the coating has two layers. Two methods were used to make the film into multiple layers. One is a method of forming a film layer by layer, applying an inner layer substance, melting and solidifying this by heat treatment to form a first layer film, and then applying an outer layer substance, followed by heat treatment. This was melted and solidified to form a final two-layer coating. The first heat treatment in this case is shown in Tables 4 and 6 as “intermediate heat treatment” and the heat treatment after the outer layer is applied as “final heat treatment”.
The other method is to apply a substance to be an inner layer, apply a substance to be an outer layer without performing a heat treatment as it is, and then melt and solidify the inner layer substance and the outer layer substance by one heat treatment to form a film. Is the method. In this case, the “intermediate heat treatment” column is “−”, and the treatment conditions are described only in the “final heat treatment” column.

The adhesion of the film was evaluated by visually observing the film peeling state of the deformed part when a 2 kg ball head weight was dropped from a height of 2 m and deformed.
The film properties were evaluated by visually observing the film after film formation by heat treatment, and evaluating the occurrence of film abnormalities such as film peeling, black spots, and cloudiness.
Regarding the adhesion and properties of the film, evaluation was indicated as x: problematic, △: usable (conventional film level), ◯: good, ◎: very good.
Regarding the magnetic characteristics, since the change in magnetic flux density due to the application of the present invention is small, the effect was evaluated by iron loss. As for the iron loss, the iron loss W15 / 50 was measured by a 55 mm square SST test, and the average value in the rolling direction of the coil and the direction perpendicular thereto was determined. Since the iron loss greatly varies depending on the components of the steel sheet and the heat history, the effect of the invention was evaluated by the difference in iron loss compared to a material that was not coated with a substance and was subjected to the same heat treatment as the film forming material.

Various characteristics are shown in Tables 3 to 6.
Steel numbers 1, 2, 15, 16, 25, 26, 29-31, 34, 39 do not contain a specific element in the applied substance, or even if it does not show an effect due to insufficient amount or undesirable treatment conditions It is. Other than this, the specific substance is concentrated at the interface between the film and the steel sheet, and the film adhesion strength is increased, so that the tension on the steel sheet by the film acts sufficiently and an effect of improving iron loss appears. In particular, when a sufficient amount of a specific substance is contained in the innermost layer, the adhesion by the innermost layer is remarkably improved, and good adhesion can be secured even when a large tension is applied to the film. Moreover, when the surface layer is made of a component closer to glass, the film properties are good.

Steel numbers 45 to 47 were obtained by cutting out a 55 mm SST sample from the steel sheet on which the first layer (innermost layer) film was formed, and stacking five layers of the sample coated with a film-forming substance on each side, followed by heat treatment. The eye film was formed and laminated at the same time.
Steel Nos. 48 to 52 were obtained by cutting out a 55 mm SST sample from a steel sheet produced without forming a film, heat-treating five sheets coated with a film-forming substance on both sides, and laminating at the same time as forming the film. Steel Nos. 48 to 50 were coated with the first layer, then heat-treated at a relatively low temperature for a short time to form a film, and then the second layer was coated, laminated and subjected to final heat treatment. Steel numbers 51 and 52 were laminated in a state where only two layers were applied, and the laminated steel sheets were fixed simultaneously with the formation of the film by a single heat treatment.

The iron loss of a 55 mm square SST sample in which five steel plates thus obtained were stacked was measured and evaluated. In addition, the film thickness in a table | surface has described the film thickness at the time of performing the same application | coating and heat processing to one steel plate.
As a result, even when film formation and lamination are performed in the manufacturing process of motors and transformer cores by the user of the steel sheet, the prescribed effect can be obtained by satisfying the conditions of the film of the present invention. Show.

  From the above results, the electrical steel sheet satisfying the conditions of the coating of the present invention achieves both the improvement of the adhesion of the coating and the application of tension to the base steel sheet, and the electrical steel sheet as a constituent member. By using it, it can be seen that it is possible to obtain an electrical component having no magnetic circuit short circuit or the like and having improved magnetic properties even when used for a long time.

  In general, the present invention is not limited to transformer parts using directional electromagnetic steel sheets and motor parts using non-oriented electromagnetic steel sheets, and electrical and magnetic properties are required regardless of the type and application of the electromagnetic steel sheets. Applicable to all electrical components.

Claims (20)

  An electrical component having a magnetic steel sheet processed into a predetermined shape as a constituent member, wherein the magnetic steel sheet is C: 0.07% or less (including 0), Si: 7.0% or less (0 Mn: 6.5% or less (including 0), P: 0.30% or less (including 0), S: 0.080% or less (including 0), Al: 8.0% or less (Including 0), N: 0.070% or less (including 0), O: 0.070% or less (including 0) on the surface of the base steel sheet containing a oxide having a multilayer structure About Ni, Co, Cr, Cu, Mo, Nb, Mn, or about two or more elements (concentration at the concentration site at the interface between the mother steel plate surface and the coating) / (on the mother steel plate surface) Average concentration) ≧ 2.0 and (concentration at the concentrated portion at the interface between the mother steel sheet surface and the coating) / (average concentration in the innermost layer of the coating) An electrical component characterized by ≧ 2.0.   2. The electrical component according to claim 1, wherein the electromagnetic steel sheet has a concentration at the interface between the surface of the base steel sheet and the coating with respect to one or more elements of Ni, Co, Cr, Cu, Mo, Nb, and Mn. An electrical component characterized in that the concentration of the formation site is 0.10% by mass or more.   3. The electrical component according to claim 1, wherein the electromagnetic steel sheet has an average depth of irregularities at the interface between the surface of the base steel sheet and the coating of 5.0 μm or less.   The electrical component according to any one of claims 1 to 3, wherein the electromagnetic steel sheet has an average period of irregularities at the interface between the surface of the base steel sheet and the coating of 15.0 µm or less.   5. The electrical component according to claim 1, wherein the magnetic steel sheet is, in the innermost layer of the coating, in mass%, Ni: 0.5% or more, Co: 0.5% or more, Cr : Containing 0.5% or more, Cu: 0.5% or more, Mo: 0.5% or more, Nb: 0.5% or more, Mn: 0.5% or more And electrical parts.   The electrical component according to any one of claims 1 to 5, wherein the electrical steel sheet is one of Ni, Co, Cr, Cu, Mo, Nb, and Mn, or two or more elements (of the coating). An electrical component characterized in that the average concentration in the innermost layer) / (average concentration in the base steel plate)> 1.00.   The electrical component according to any one of claims 1 to 6, wherein the electromagnetic steel sheet is any one of Ni, Co, Cr, Cu, Mo, Nb, Ti, B, and Mn, or two or more elements. , (Average concentration in innermost layer of coating) / (Average concentration in layers other than innermost layer of coating)> 2. The electrical component according to any one of claims 1 to 7, wherein the electrical steel sheet has a coating average of 30% by mass or more with respect to the SiO ₂ concentration of the coating, and (an average concentration in a layer other than the innermost layer). ) / (Average concentration in the innermost layer)> 1.0.   The electrical component according to any one of claims 1 to 8, wherein the magnetic steel sheet has an average thickness of an innermost layer of a film forming a multilayer structure of 10.0 µm or less, and all An electrical component having a film thickness of ½ or less.   10. The electrical component according to claim 1, wherein the electromagnetic steel sheet satisfies (thickness of the entire coating) / (steel plate thickness) ≦ 1/10.   The electrical component according to any one of claims 1 to 10, wherein the electromagnetic steel sheet has a tension of 1 MPa or more generated in the mother steel sheet due to a film.   The electrical component according to any one of claims 1 to 11, wherein the electrical steel sheet has {[(because of the innermost layer] with respect to the tension generated on the surface of the base steel sheet and the thickness of each layer due to the film. Tension) / (tension caused by a layer other than the innermost layer)] / (thickness of the innermost layer)} × (thickness of a layer other than the innermost layer) <1.00.   It is a manufacturing method of the electrical component of any one of Claims 1-12, Comprising: On the surface of the mother steel plate of an electromagnetic steel plate, 1 layer of the substance or mixture mainly based on an oxide is applied, or the said substance or The composition of the mixture is changed so as to form a multi-layer, and then heat-treated at a temperature at which one or more oxides contained in the coating of the applied layer are melted, A method of manufacturing an electrical component, comprising forming a multi-layered film by performing heat treatment at least once, and processing the electromagnetic steel sheet on which the film is formed into a predetermined shape.   It is a manufacturing method of the electrical component of any one of Claims 1-12, Comprising: After processing the base plate of an electromagnetic steel plate into a predetermined shape, when manufacturing an electrical component using this processed base plate In addition, a single layer of a substance or mixture mainly composed of oxide is applied to the surface of the mother steel plate, or it is applied so as to form a multi-layer by changing the composition of the substance or mixture. Forming a multi-layer coating on the surface of the mother steel sheet by heat-treating at or above the temperature at which one or more of the oxides contained in the material melt, and performing the above application and heat treatment at least once A method of manufacturing an electrical component characterized by the above.   It is a manufacturing method of the electrical component of any one of Claims 1-12, Comprising: On the surface of the mother steel plate of an electromagnetic steel plate, 1 layer of the substance or mixture mainly based on an oxide is applied, or the said substance or The composition of the mixture is changed so as to form a multi-layer, and then heat-treated at a temperature at which one or more oxides contained in the coating of the applied layer are melted, When a magnetic film is formed on the surface of the mother steel sheet by performing heat treatment at least once, and the electrical steel sheet on which the film is formed is processed into a predetermined shape, an electrical component is manufactured using the processed electromagnetic steel sheet. A method for producing an electrical component, wherein a coating having a multilayer structure is formed on the surface of a mother steel plate by performing the application and heat treatment again once or more on the surface of the electromagnetic steel plate.   16. The method of manufacturing an electrical component according to claim 14 or 15, wherein the heat treatment performed after the electromagnetic steel sheet is processed into a predetermined shape is performed by post-processing strain relief annealing.   The method of manufacturing an electrical component according to any one of claims 13 to 16, wherein the heat treatment for melting one or more of the oxides is performed at a temperature range of 400 to 1200 ° C and 0.1 to 3600. A method for producing an electrical component, which is performed by heating for a second.   The method for manufacturing an electrical component according to any one of claims 13 to 17, wherein the heat treatment for melting one or more of the oxides is performed in an atmosphere with a dew point ≤ 0 ° C. A method for manufacturing electrical parts.   The method of manufacturing an electrical component according to any one of claims 13 to 18, wherein the substance or mixture for forming the surface film is applied by a dry process.   The method for manufacturing an electrical component according to any one of claims 13 to 19, wherein one or two kinds of oxides in a layer of a substance or mixture mainly composed of oxides applied to the surface of the mother steel plate. A method for producing an electrical component, characterized in that when a heat treatment for melting the above is performed, a stress applied to the surface of the mother steel plate is applied in a state where a tension of 1 MPa or more is applied.