WO2024136278A1 - Insulation coating composition, grain-oriented electrical steel sheet comprising same, and method of manufacturing grain-oriented electrical steel sheet - Google Patents

Insulation coating composition, grain-oriented electrical steel sheet comprising same, and method of manufacturing grain-oriented electrical steel sheet Download PDF

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WO2024136278A1
WO2024136278A1 PCT/KR2023/020527 KR2023020527W WO2024136278A1 WO 2024136278 A1 WO2024136278 A1 WO 2024136278A1 KR 2023020527 W KR2023020527 W KR 2023020527W WO 2024136278 A1 WO2024136278 A1 WO 2024136278A1
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steel sheet
nitrate
electrical steel
phosphate
grain
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PCT/KR2023/020527
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French (fr)
Korean (ko)
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김현정
최헌조
권민석
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주식회사 포스코
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Publication of WO2024136278A1 publication Critical patent/WO2024136278A1/en

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  • It relates to electrical steel sheets, and more specifically, to an insulating coating composition, a grain-oriented electrical steel sheet containing the same, and a method of manufacturing the same.
  • Electrical steel is a product used as a material for transformers, motors, and electrical devices. Unlike general carbon steel, which places importance on processability such as mechanical properties, it is a functional product that places importance on electrical properties.
  • the electrical properties required for the electrical steel sheet include low iron loss, high magnetic flux density, magnetic permeability, and high space factor.
  • the electrical steel sheet is further divided into oriented electrical steel sheet and non-oriented electrical steel sheet.
  • the grain-oriented electrical steel sheet is an electrical steel sheet with excellent magnetic properties in the rolling direction by forming a Goss texture ( ⁇ 110 ⁇ 001> texture) throughout the steel sheet using an abnormal grain growth phenomenon called secondary recrystallization.
  • non-oriented electrical steel sheet is an electrical steel sheet whose magnetic properties are uniform in all directions on the rolled sheet.
  • the grain-oriented electrical steel sheet In order to ensure stability over time in the grain-oriented electrical steel sheet, it is important to secure physical properties such as surface roughness, gloss, and uniformity of the chromaticity of the insulating film after insulating coating. For example, in the case of the grain-oriented electrical steel sheet, it has excellent durability in extreme high-temperature and high-humidity environments, such as SRA processing, has a higher effect than before in extreme corrosion resistance environments, and needs to secure heat resistance at high temperatures. .
  • the grain-oriented electrical steel sheet has a general coating composition, consisting of an MgO coating on the base material and an insulating coating on the upper surface.
  • the insulating coating is typically composed of phosphate, silica, and nitrate.
  • Typical conditions for conventional corrosion resistance are NaCl 5%, 60°C, 8 hours. Additionally, for automobile parts used for a long time, the extreme conditions for corrosion resistance are 5% NaCl, 65°C, 100 hours in salt spray.
  • the general condition for weather resistance is 72 hours at 98% moisture and 60°C, but the extreme condition for weatherability is 100 hours at 98% moisture and 65°C.
  • the general insulating coating has excellent corrosion resistance, but has the disadvantage of being vulnerable to weather resistance and having a sticky surface. This sticky characteristic may cause problems with adhesion properties when winding the coil.
  • the technical problem to be solved by the present invention is to provide an insulating coating composition for grain-oriented electrical steel sheets containing a coating material that does not separate the film from the material even in a high temperature and high humidity environment.
  • Another technical problem to be solved by the present invention is to provide a grain-oriented electrical steel sheet coated with an insulating coating composition having the above-described advantages.
  • Another technical problem to be solved by the present invention is to provide a method of manufacturing a grain-oriented electrical steel sheet having the above-mentioned advantages.
  • an insulating coating composition for a grain-oriented electrical steel sheet includes phosphate, silica, nitrate, and an oxidizing agent, wherein the silica contains 50 to 400 parts by weight of solid content based on 100 parts by weight of the phosphate, and the phosphate
  • the mixing ratio of the silica solid content to solid content is 0.3 to 3.9
  • the oxidizing agent may include 0.5 to 10.0 parts by weight of solid content based on 100 parts by weight of the phosphate.
  • the nitrate is aluminum nitrate (Al(NO 3 ) 3 ), cobalt nitrate (Co(NO 3 ) 2 ), calcium nitrate (Ca(NO 3 ) 2 ), and strontium nitrate (Sr(NO 3 ) 2 ), zinc nitrate (Zn(NO 3 ) 2 ), manganese nitrate (Mn(NO 3 ) 2 ), magnesium nitrate (Mg(NO 3 ) 2 ), and silver nitrate (AgNO 3 ).
  • Al(NO 3 ) 3 aluminum nitrate
  • Co(NO 3 ) 2 cobalt nitrate
  • Ca(NO 3 ) 2 calcium nitrate
  • Zn(NO 3 ) 2 zinc nitrate
  • Mn(NO 3 ) 2 manganese nitrate
  • Mg(NO 3 ) 2 magnesium nitrate
  • silver nitrate AgNO 3
  • the nitrate is aluminum nitrate (Al(NO 3 ) 3 ), cobalt nitrate (Co(NO 3 ) 2 ), calcium nitrate (Ca(NO 3 ) 2 ), and strontium nitrate (Sr(NO 3 ) 2 ), zinc nitrate (Zn(NO 3 ) 2 ), manganese nitrate (Mn(NO 3 ) 2 ), magnesium nitrate (Mg(NO 3 ) 2 ), and silver nitrate (AgNO 3 ).
  • the nitrate may include 5 to 100 parts by weight of solid content based on 100 parts by weight of the phosphate.
  • the oxidizing agent may include at least one of HClO 4 , NaClO, NaClO 4 , KMnO 4 , NaIO 4 , OsO 4 , H 2 O 2 , and Ca(ClO) 2 .
  • a grain-oriented electrical steel sheet includes an electrical steel sheet base material and an insulating film located on the surface of the electrical steel sheet base material, wherein the insulating film includes phosphate, silica, nitrate, and an oxidizing agent, Silica includes a solid content of 50 to 400 parts by weight based on 100 parts by weight of phosphate, the mixing ratio of the silica solid content to the phosphate solid content is 0.3 to 3.9, and the oxidizing agent has a solid content of 0.5 to 10.0 parts by weight based on 100 parts by weight of the phosphate. May include wealth.
  • a method for manufacturing a grain-oriented electrical steel sheet includes preparing an electrical steel sheet base material, applying an insulating coating composition to the surface of the electrical steel sheet base material, and curing the insulating coating composition.
  • the insulating coating composition includes phosphate, silica, nitrate, and an oxidizing agent, the silica includes 50 to 400 parts by weight of solid content based on 100 parts by weight of phosphate, and the mixing ratio of the silica solid content to the phosphate solid content is 0.3.
  • the oxidizing agent includes a solid content of 0.5 to 10.0 parts by weight based on 100 parts by weight of the phosphate
  • the step of curing the insulating coating composition may be performed in the range of 800 to 900 ° C. for 30 seconds to 180 seconds.
  • the step of applying an insulating coating composition to the surface of the electrical steel substrate includes adding and mixing phosphate and silica, adding nitrate to the mixed solution, and then adding an oxidizing agent. can do.
  • the step of preparing an electrical steel sheet base includes preparing a steel slab, heating the steel slab, hot rolling the heated steel slab to produce a hot rolled steel sheet, and cold rolling the hot rolled steel sheet. It may include manufacturing a cold rolled steel sheet, performing primary recrystallization annealing on the cold rolled sheet, applying an annealing separator on the primary recrystallization annealed steel sheet, and performing secondary recrystallization annealing.
  • the step of applying an annealing separator on the primary recrystallization annealed steel sheet may include applying the annealing separator in a range of 1 to 5 g/m 2 .
  • the secondary recrystallization annealing step includes a cracking step and a temperature raising step, the cracking step may be performed in the range of 650 to 750 ° C., and the temperature raising step may be performed in the range of 1,100 to 1,250 ° C.
  • the temperature increasing step may be performed at a temperature increasing rate in the range of 10 to 20 °C/hr.
  • the cracking step may be performed in an atmosphere of two or more gases selected from hydrogen gas, nitrogen gas, and inert gas gas.
  • the temperature raising step may be performed in a hydrogen atmosphere.
  • the insulating coating composition according to an embodiment of the present invention has excellent durability and extreme corrosion resistance in a high temperature and high humidity environment by adding an oxidizing agent to remove the hydrogen group of phosphate in the grain-oriented electrical steel sheet, and has very high processability such as SRA.
  • An insulating coating composition for grain-oriented electrical steel sheets with excellent heat resistance at high temperatures is provided.
  • a grain-oriented electrical steel sheet coated with the above-described insulating coating composition can be provided.
  • a method for manufacturing a grain-oriented electrical steel sheet having the above-mentioned advantages can be provided.
  • first, second, and third are used to describe, but are not limited to, various parts, components, regions, layers, and/or sections. These terms are used only to distinguish one portion, component, region, layer or section from another portion, component, region, layer or section. Accordingly, the first part, component, region, layer or section described below may be referred to as the second part, component, region, layer or section without departing from the scope of the present invention.
  • % means weight%, and 1ppm is 0.0001% by weight.
  • further including an additional element means replacing the remaining iron (Fe) by the amount of the additional element.
  • the insulating coating composition for a grain-oriented electrical steel sheet may include phosphate, silica, nitrate, and an oxidizing agent.
  • the phosphate is a metal phosphate and may satisfy M(H 2 PO 4 ) or M(HPO 4 ).
  • the M may include Mg, Al, Zn, Ca, or a combination thereof.
  • M may be a phosphate containing Mg and Al.
  • the silica is a necessary ingredient to reduce iron loss by applying tension to the steel sheet.
  • the phosphate acts as a binder for silica, thereby improving the film forming properties of the coating and improving film adhesion.
  • the silica may be a basic or acidic material.
  • the silica may include 50 to 400 parts by weight of solid content based on 100 parts by weight of phosphate. Specifically, the silica may include 80 to 200 parts by weight, more specifically 135 to 180 parts by weight, and more specifically 145 to 160 parts by weight based on 100 parts by weight of the phosphate.
  • the range of silica is outside the upper limit, it can be confirmed that it has a poor effect in stickiness or solution stability. If the range of silica is outside the lower limit, there is a problem that the effect of providing tension to the steel sheet is insufficient.
  • the silica may have an average particle diameter ranging from 5 to 20 nm. If the average particle diameter of the silica is outside the upper limit of the above range, the surface area per unit mass becomes small, which slows the condensation reaction rate, and there is an uneconomical problem because the heat treatment temperature must be increased to increase the reaction rate. If the average particle diameter of the silica is outside the lower limit of the above range, the condensation reaction rate is fast, agglomeration occurs, and there is a problem of causing color deviation defects on the surface.
  • the silica may be composed of at least one nanoparticle having a different average particle diameter.
  • the silica may be used by mixing at least one or more silica nanoparticles with different average particle diameters to form an insulating film with excellent film properties.
  • the mixing ratio of the silica solid content to the phosphate solid content may be 0.3 to 3.9. Specifically, the mixing ratio may be 0.5 to 2.0.
  • the silica and the phosphate are mixed in the above mixing ratio, the advantages of excellent adhesion to the base material, heat resistance, weather resistance, and corrosion resistance can be realized when manufacturing electrical steel sheets.
  • the nitrate may be a component that plays a role in corrosion resistance and weather resistance.
  • the nitrate is aluminum nitrate (Al(NO 3 ) 3 ), cobalt nitrate (Co(NO 3 ) 2 ), calcium nitrate (Ca(NO 3 ) 2 ), and strontium nitrate (Sr(NO 3 ) 2 ), zinc nitrate (Zn(NO 3 ) 2 ), manganese nitrate (Mn(NO 3 ) 2 ), magnesium nitrate (Mg(NO 3 ) 2 ), and silver nitrate (AgNO 3 ).
  • the nitrate may include 5 to 100 parts by weight of solid content based on 100 parts by weight of the phosphate. Specifically, the nitrate has a solid content of 15 to 80 parts by weight, more specifically, a solid content of 20 to 60 parts by weight, more specifically, a solid content of 22 to 51 parts by weight, and more specifically, 22 to 28 parts by weight, based on 100 parts by weight of the phosphate. It may include weight parts.
  • nitrate content is outside the upper limit of the above range, there is a risk of fire. If the nitrate content is outside the lower limit of the above range, there is a problem with weather resistance.
  • the oxidizing agent may serve as an additive for removing hydrogen groups (H) from phosphates such as M(H 2 PO 4 ) or M(HPO 4 ).
  • the oxidizing agent removes H from phosphates such as M(H 2 PO 4 ) or M(HPO 4 ), which have sticky properties, by removing the hydrogen group from the phosphate, thereby forming M(PO), which does not have sticky properties. 4 ) can play a role in causing the reaction.
  • the oxidizing agent may include at least one of HClO 4 , NaClO, NaClO 4 , KMnO 4 , NaIO 4 , OsO 4 , H 2 O 2 , and Ca(ClO) 2 .
  • the oxidizing agent may include oxidizing phosphate to remove a hydrogen group.
  • the oxidizing agent may include 0.5 to 10.0 parts by weight of solid content based on 100 parts by weight of the phosphate.
  • the oxidizing agent may include 0.8 to 5.0 parts by weight, more specifically, 1.0 to 3.0 parts by weight, based on 100 parts by weight of the phosphate.
  • the content of the oxidizing agent is outside the upper limit of the above range, it may have a poor effect on stickiness resistance and solution stability. If the content of the oxidizing agent is outside the lower limit of the above range, there is a problem in that the advantage of reducing stickiness due to the addition of the oxidizing agent is not realized.
  • the silica may be an acidic material.
  • a basic material as the silica, there is a problem in that the phosphate and nitrate are not stable and gelation occurs.
  • a grain-oriented electrical steel sheet includes an electrical steel sheet base material and an insulating film located on the surface of the electrical steel sheet base material.
  • the insulating coating includes phosphate, silica, nitrate, and an oxidizing agent, and the detailed description of the phosphate, silica, nitrate, and oxidizing agent is the same as the content of the insulating coating composition described above to the extent that it does not contradict.
  • a method for manufacturing a grain-oriented electrical steel sheet includes preparing an electrical steel sheet base material, applying an insulating coating composition to the surface of the electrical steel sheet base material, and curing the insulating coating composition.
  • the step of preparing the electrical steel sheet base includes preparing a steel slab, heating the steel slab, hot rolling the heated steel slab to produce a hot rolled steel sheet, and cold rolling the hot rolled steel sheet to produce a cold rolled steel sheet. It may include manufacturing, primary recrystallization annealing of the cold rolled sheet, applying an annealing separator on the primary recrystallization annealing, and performing secondary recrystallization annealing.
  • the steel slab In the step of heating the steel slab, the steel slab may be heated to a temperature of 1,300° C. or lower. When heating the steel slab to the above-mentioned temperature range, coarse growth of the columnar crystals of the slab can be prevented, thereby preventing cracks in the plate from occurring during the hot rolling process. Specifically, the step of heating the steel slab may be heated to a temperature of 1,050 to 1,300 °C.
  • the heated steel slab can be hot rolled to produce a hot rolled steel sheet.
  • the hot rolling temperature is not limited, and in one embodiment, hot rolling may be completed at a temperature of 950° C. or lower.
  • annealing the hot rolled steel sheet may be performed after manufacturing the hot rolled steel sheet.
  • the step of annealing the hot rolled steel sheet can homogenize the uneven microstructure and precipitates of the hot rolled steel sheet.
  • the step of annealing the hot rolled steel sheet may be performed at a temperature range of 800 to 1,300 °C.
  • a step of manufacturing a cold rolled steel sheet may be performed by cold rolling the hot rolled steel sheet.
  • the cold rolling step may include one cold rolling or two or more cold rollings including intermediate annealing.
  • the primary recrystallization annealing step may include a decarburization step and a nitriding step.
  • the decarburization step and the nitridation step may be performed in any order.
  • a nitriding step may be performed after a decarburization step, or a decarburization step may be performed after a nitriding step.
  • it may include the step of primary recrystallization by simultaneously performing decarburization annealing and nitriding treatment on a cold rolled steel sheet obtained through cold rolling.
  • the decarburization step and the sieving step can be performed simultaneously.
  • the nitriding step is for nitriding the steel sheet, is a step of introducing nitrogen ions into the steel sheet, and is a step of precipitating precipitates such as (Al, Si, Mn)N or AlN, which are crystal growth inhibitors.
  • the grain-oriented electrical steel sheet can be nitrided so that the nitrogen content is 0.01% or less.
  • the annealing temperature may be within the range of 800 to 950°C.
  • the annealing temperature range is outside the upper limit, the recrystallized grains grow coarsely and the driving force for crystal growth decreases, resulting in the problem that stable secondary recrystallization cannot be formed. If the annealing temperature range exceeds the lower limit, there is a problem that excessive time is taken during decarburization.
  • the primary recrystallization annealing step may be performed in a nitrogen, hydrogen, or mixed gas atmosphere.
  • the gas atmosphere may be an ammonia gas atmosphere.
  • the gas atmosphere may be performed in a wet atmosphere or a dry atmosphere.
  • an annealing separator can be applied to the steel sheet.
  • an annealing separator containing MgO as a main component can be used as the annealing separator.
  • the application amount of the annealing separator may be in the range of 1 to 5 g/m 2 .
  • the application amount of the annealing separator is outside the upper limit of the above range, there is a problem affecting secondary recrystallization. If the application amount of the annealing separator is outside the lower limit of the above range, there is a problem in that it is difficult to form a film smoothly.
  • the steps for performing secondary recrystallization annealing include forming a ⁇ 110 ⁇ 001> texture by secondary recrystallization, forming a glassy film by reacting MgO with the oxide layer formed during primary recrystallization, providing insulation, and removing impurities that impede magnetic properties. is to remove.
  • the secondary recrystallization annealing step may include a cracking step and a temperature raising step.
  • the cracking step may be performed in the range of 650 to 750 °C
  • the temperature raising step may be performed in the range of 1,100 to 1,250 °C. If the temperature is outside the above range, it is difficult to form an appropriate film.
  • the temperature increasing step may be performed at a temperature increasing rate in the range of 10 to 20 °C/hr. Specifically, the temperature increase rate may be performed in the range of 13 to 17 °C/hr.
  • the temperature increase rate is outside the upper limit of the above range, there is a problem that the coating film is decomposed due to decomposition of phosphate. If the temperature increase rate is outside the lower limit of the above range, there is a problem of poor corrosion resistance and weather resistance due to non-curing of the silica.
  • the cracking step may be performed in an atmosphere of at least two of hydrogen gas, nitrogen gas, and inert gas gas.
  • the temperature raising step may be performed in a hydrogen gas atmosphere. Specifically, as a method of secondary recrystallization annealing, in the temperature increase stage before secondary recrystallization occurs, a mixed gas of nitrogen and hydrogen is maintained to protect nitride, which is a grain growth inhibitor, so that secondary recrystallization can develop well. After recrystallization is completed, in the cracking stage, impurities are removed by maintaining a 100% hydrogen atmosphere for a long time.
  • the step of applying an insulating coating composition to the surface of the electrical steel substrate includes adding and mixing phosphate and silica; Adding nitrate to the mixed solution; and then adding an oxidizing agent.
  • the phosphate, the silica, the nitrate, and the oxidizing agent are the same as those described in the above-described insulating coating composition to the extent not inconsistent with the content.
  • curing the insulating coating may be performed at a temperature range of 800 to 900 °C. If the temperature exceeds the upper limit of the above temperature range, there is a problem that the weather resistance and corrosion resistance of the insulating film deteriorate. If the temperature exceeds the lower limit of the above temperature range, curing of the silica sol does not occur, which may cause problems with corrosion resistance and weather resistance.
  • curing the insulating coating may be performed for a period of 30 to 240 seconds. Specifically, the time may be performed for a period of 45 to 180 seconds.
  • an aluminum and magnesium phosphate solution mixed with 67% phosphate solids having the content shown in Table 1 below was prepared, and then, the solid content having the content shown in Table 1 below was mixed to 30%. % mixed colloidal silica solution was added and mixed.
  • a nitrate solution mixed with a 50% solid content such as aluminum nitrate or magnesium nitrate corresponding to the conversion coating material with the content in Table 1 below was added, and then HClO 4 , NaClO, and NaClO with the content in Table 1 below were added.
  • An insulating coating composition solution having the composition shown in Table 1 below was prepared by adding an oxidizing agent mixed with a solid content of 50%, such as NaClO 4 .
  • the solution of the prepared insulating coating composition is applied onto the MgO-treated steel sheet. Afterwards, it was dried between 700 and 950°C for 30 to 240 seconds, and then the skid resistance, weather resistance, heat resistance, corrosion resistance, and solution stability were evaluated.
  • the above-mentioned stickiness is to evaluate the degree of stickiness.
  • Test 1 To compare the amount of wear according to the slip distance, Test 1 and the sphere diameter of 12.7mm, pressure load of 50N, rotation speed of 50rpm, rotation radius of 15mm, slip distance of 200m (Test 1), At the same load and rotation speed, the rotation radius is varied to 10 mm and the slip distance is varied to 10 m to evaluate the stickiness using the actual friction coefficient.
  • the friction coefficient was calculated as the friction force against the vertical load (friction force/vertical load). If the friction coefficient was lower than 0.4 and good, it was marked as “OK”; if it was bad and higher than 0.4, it was marked as “NG.”
  • a salt spray test was conducted with NaCl 5%, 100 RH, 65°C, 8 hours.
  • PO 4 is a substance that is not dissolved and exists as a powder. The powder remaining in the filter is weighed and if powder is present, it can be determined that HPO 4 has been removed by the oxidizing agent.
  • Cl tracking method Dissolve the 2x2 CM size coating in 100 mL of 10% NaOH. If Cl is present in the solution, it can be considered that Cl has been added.
  • hydrogen groups can be removed from the oxidizing agent such as M(H 2 PO 4 ) or M(HPO 4 ) according to the following reaction equation.
  • Table 2 below shows that the composition of the insulating coating composition for grain-oriented electrical steel sheets was controlled in the content range shown in Table 2 below, aluminum nitrate was used as the nitrate, and HClO 4 was used as the oxidizing agent, in the same manner as in Experimental Examples 1 to 8. An insulating coating composition was prepared and evaluated.
  • Experiments 27 to 36 in addition to controlling the composition of the insulating coating composition for grain-oriented electrical steel within the content range shown in Table 4, adding magnesium nitrate in addition to aluminum nitrate as a nitrate, and using HClO 4 as an oxidizing agent, Experiment Example 1
  • the insulating coating composition was prepared in the same manner as in 9 to 9, and was evaluated.
  • Table 5 below evaluates the stickiness resistance, weather resistance, and corrosion resistance of insulating coating compositions for grain-oriented electrical steel sheets of the same composition when the curing temperature and curing time are adjusted as shown in Table 4 below.
  • the present invention is not limited to the above embodiments and/or examples, but can be manufactured in various different forms, and those skilled in the art may change the technical idea or essential features of the present invention. You will be able to understand that it can be implemented in another specific form without doing so. Therefore, the implementation examples and/or embodiments described above should be understood in all respects as illustrative and not restrictive.

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Abstract

The present invention relates to a coating composition for a grain-oriented electrical steel sheet, a grain-oriented electrical steel sheet comprising same, and a method of manufacturing a grain-oriented electrical sheet. According to one embodiment of the present invention, a coating composition for a grain-oriented electrical steel sheet comprises phosphate, silica, nitrate, and an oxidizer, wherein the silica comprises, on the basis of 100 parts by weight of the phosphate, 50 to 400 parts by weight of solids, the mixing ratio of the silica solids to phosphate solids is 0.3 to 3.9, and the oxidizer may comprise 0.5 to 10.0 parts by weight of solids, on the basis of 100 parts by weight of the phosphate.

Description

절연 피막 조성물, 이를 포함하는 방향성 전기강판, 및 방향성 전기강판의 제조 방법Insulating coating composition, grain-oriented electrical steel sheet containing the same, and method for manufacturing grain-oriented electrical steel sheet
전기강판에 관한 것으로서, 더욱 상세하게는 절연 피막 조성물, 이를 포함하는 방향성 전기강판, 및 이의 제조 방법에 관한 것이다.It relates to electrical steel sheets, and more specifically, to an insulating coating composition, a grain-oriented electrical steel sheet containing the same, and a method of manufacturing the same.
전기강판은 변압기, 모터, 전기기기용 소재로 사용되는 제품으로서, 기계적 특성과 같은 가공성을 중요시하는 일반 탄소강과는 달리, 전기적 특성을 중요시하는 기능성 제품이다. 상기 전기강판에서 요구되는 상기 전기적 특성으로는 철손이 낮을 것, 자속밀도, 투자율, 및 점적율이 높을 것과 같은 것이 있다.Electrical steel is a product used as a material for transformers, motors, and electrical devices. Unlike general carbon steel, which places importance on processability such as mechanical properties, it is a functional product that places importance on electrical properties. The electrical properties required for the electrical steel sheet include low iron loss, high magnetic flux density, magnetic permeability, and high space factor.
상기 전기강판은 다시 방향성 전기강판과 무방향성 전기강판으로 구분된다. 상기 방향성 전기강판은 2차 재결정으로 불리는 비정상 결정립 성장 현상을 이용하여 Goss 조직({110}<001> 집합조직)을 강판 전체에 형성시켜 압연방향의 자기적 특성이 뛰어난 전기강판이다. 이에 반해, 무방향성 전기강판은 압연판 상의 모든 방향으로 자기적 특성이 균일한 전기강판이다.The electrical steel sheet is further divided into oriented electrical steel sheet and non-oriented electrical steel sheet. The grain-oriented electrical steel sheet is an electrical steel sheet with excellent magnetic properties in the rolling direction by forming a Goss texture ({110}<001> texture) throughout the steel sheet using an abnormal grain growth phenomenon called secondary recrystallization. On the other hand, non-oriented electrical steel sheet is an electrical steel sheet whose magnetic properties are uniform in all directions on the rolled sheet.
상기 방향성 전기강판에서 시간경과에 따른 안정성 확보를 위해, 절연 코팅 후 절연 피막의 표면 조도, 광택도, 색도 피막의 균일성과 같은 특성에서의 물성 확보가 중요하다. 예를 들어, 상기 방향성 전기강판의 경우, 극한의 고온 다습 환경, 예를 들어 SRA 가공 시 내구성이 우수하고, 극한의 내식성 환경에 대해 기존보다 높은 효과를 가지며, 고온에서 내열성을 확보할 필요가 있다.In order to ensure stability over time in the grain-oriented electrical steel sheet, it is important to secure physical properties such as surface roughness, gloss, and uniformity of the chromaticity of the insulating film after insulating coating. For example, in the case of the grain-oriented electrical steel sheet, it has excellent durability in extreme high-temperature and high-humidity environments, such as SRA processing, has a higher effect than before in extreme corrosion resistance environments, and needs to secure heat resistance at high temperatures. .
상기 방향성 전기강판은 일반적인 코팅 구성으로 모재 위에 MgO 코팅과 상부 표면에 절연 코팅으로 구성되어 있다. 상기 절연 코팅은 인산염, 실리카, 및 질산염으로 구성된 것이 일반적이다.The grain-oriented electrical steel sheet has a general coating composition, consisting of an MgO coating on the base material and an insulating coating on the upper surface. The insulating coating is typically composed of phosphate, silica, and nitrate.
기존의 내식성의 일반적인 조건은 NaCl 5%, 60 ℃, 8 시간이다. 또한, 장시간 사용하는 자동차 부속품의 경우, 내식성의 극한 조건은 염수분무 시 NaCl 5 %, 65 ℃, 100 시간이다. 내후성의 일반적인 조건은 98 % 수분, 60 ℃ 조건에서 72 시간이지만, 내후성의 극한 조건은 98 % 수분, 65 ℃ 조건에서 100 시간이다.Typical conditions for conventional corrosion resistance are NaCl 5%, 60°C, 8 hours. Additionally, for automobile parts used for a long time, the extreme conditions for corrosion resistance are 5% NaCl, 65°C, 100 hours in salt spray. The general condition for weather resistance is 72 hours at 98% moisture and 60℃, but the extreme condition for weatherability is 100 hours at 98% moisture and 65℃.
일반적인 상기 절연 코팅은 우수한 내식성을 가지고 있으나 내후성에 취약하고 표면이 끈끈한 스티키(Sticky)한 단점이 있다. 이러한 스티키한 특성은 권취한 코일을 권취할 경우, 접착의 성질에 있어 문제가 발생할 수 있다.The general insulating coating has excellent corrosion resistance, but has the disadvantage of being vulnerable to weather resistance and having a sticky surface. This sticky characteristic may cause problems with adhesion properties when winding the coil.
따라서, 상기 절연 코팅에 있어서, 다습한 환경에서도 막과 소재가 분리되지 않는 방향성 전기강판용 크롬 프리 인산염 코팅을 개발하고, 인산염에 의해 표면이 끈적끈적한 성질을 가지고 있는 다습한 환경에 취약한 문제를 해결하는 절연 코팅 조성물의 개발이 필요한 실정이다.Therefore, in the above insulating coating, we developed a chromium-free phosphate coating for grain-oriented electrical steel sheets in which the film and material do not separate even in a humid environment, and solved the problem of the surface being vulnerable to a humid environment due to the sticky nature of the phosphate. There is a need for development of insulating coating compositions.
본 발명이 해결하고자 하는 기술적 과제는 고온 다습한 환경에서도 막과 소재가 분리되지 않는 코팅 물질을 포함하는 방향성 전기강판용 절연 피막 조성물을 제공한다.The technical problem to be solved by the present invention is to provide an insulating coating composition for grain-oriented electrical steel sheets containing a coating material that does not separate the film from the material even in a high temperature and high humidity environment.
본 발명이 해결하고자 하는 다른 기술적 과제는 전술한 이점을 갖는 절연 피막 조성물로 코팅된 방향성 전기강판을 제공한다.Another technical problem to be solved by the present invention is to provide a grain-oriented electrical steel sheet coated with an insulating coating composition having the above-described advantages.
본 발명이 해결하고자 하는 또 다른 기술적 과제는 전술한 이점을 갖는 방향성 전기강판을 제조하는 방법을 제공한다.Another technical problem to be solved by the present invention is to provide a method of manufacturing a grain-oriented electrical steel sheet having the above-mentioned advantages.
본 발명의 일 실시예에 따른, 방향성 전기강판용 절연 피막 조성물은 인산염, 실리카, 질산염, 및 산화제를 포함하고, 상기 실리카는 상기 인산염 100 중량부를 기준으로, 고형분 50 내지 400 중량부를 포함하고, 상기 인산염 고형분에 대한 상기 실리카 고형분의 배합비는 0.3 내지 3.9 이며, 상기 산화제는 상기 인산염 100 중량부를 기준으로, 고형분 0.5 내지 10.0 중량부를 포함할 수 있다. 일 실시예에서, 상기 질산염은 질산알루미늄(Al(NO3)3), 질산코발트(Co(NO3)2), 질산칼슘(Ca(NO3)2), 질산스트론튬(Sr(NO3)2), 질산아연(Zn(NO3)2), 질산망간(Mn(NO3)2), 질산마그네슘(Mg(NO3)2), 및 질산은(AgNO3) 중 적어도 어느 하나를 포함할 수 있다.According to an embodiment of the present invention, an insulating coating composition for a grain-oriented electrical steel sheet includes phosphate, silica, nitrate, and an oxidizing agent, wherein the silica contains 50 to 400 parts by weight of solid content based on 100 parts by weight of the phosphate, and the phosphate The mixing ratio of the silica solid content to solid content is 0.3 to 3.9, and the oxidizing agent may include 0.5 to 10.0 parts by weight of solid content based on 100 parts by weight of the phosphate. In one embodiment, the nitrate is aluminum nitrate (Al(NO 3 ) 3 ), cobalt nitrate (Co(NO 3 ) 2 ), calcium nitrate (Ca(NO 3 ) 2 ), and strontium nitrate (Sr(NO 3 ) 2 ), zinc nitrate (Zn(NO 3 ) 2 ), manganese nitrate (Mn(NO 3 ) 2 ), magnesium nitrate (Mg(NO 3 ) 2 ), and silver nitrate (AgNO 3 ). .
*14일 실시예에서, 질산염은 질산알루미늄(Al(NO3)3), 질산코발트(Co(NO3)2), 질산칼슘(Ca(NO3)2), 질산스트론튬(Sr(NO3)2), 질산아연(Zn(NO3)2), 질산망간(Mn(NO3)2), 질산마그네슘(Mg(NO3)2), 및 질산은(AgNO3) 중 적어도 2 이상을 포함할 수 있다. 일 실시예에서, 상기 질산염은 상기 인산염 100 중량부를 기준으로, 고형분 5 내지 100 중량부를 포함할 수 있다. 일 실시예에서, 상기 산화제는 HClO4, NaClO, NaClO4, KMnO4, NaIO4, OsO4, H2O2, Ca(ClO)2 중 적어도 어느 하나를 포함할 수 있다. *In the 14-day example, the nitrate is aluminum nitrate (Al(NO 3 ) 3 ), cobalt nitrate (Co(NO 3 ) 2 ), calcium nitrate (Ca(NO 3 ) 2 ), and strontium nitrate (Sr(NO 3 ) 2 ), zinc nitrate (Zn(NO 3 ) 2 ), manganese nitrate (Mn(NO 3 ) 2 ), magnesium nitrate (Mg(NO 3 ) 2 ), and silver nitrate (AgNO 3 ). there is. In one embodiment, the nitrate may include 5 to 100 parts by weight of solid content based on 100 parts by weight of the phosphate. In one embodiment, the oxidizing agent may include at least one of HClO 4 , NaClO, NaClO 4 , KMnO 4 , NaIO 4 , OsO 4 , H 2 O 2 , and Ca(ClO) 2 .
본 발명의 다른 실시예에 따른, 방향성 전기강판은 전기강판 기재 및 상기 전기강판 기재의 표면 상에 위치하는 절연피막을 포함하고, 상기 절연피막은 인산염, 실리카, 질산염, 및 산화제를 포함하고, 상기 실리카는 인산염 100 중량부를 기준으로, 고형분 50 내지 400 중량부를 포함하고, 상기 인산염 고형분에 대한 상기 실리카 고형분의 배합비는 0.3 내지 3.9 이고, 상기 산화제는 상기 인산염 100 중량부를 기준으로, 고형분 0.5 내지 10.0 중량부를 포함할 수 있다.According to another embodiment of the present invention, a grain-oriented electrical steel sheet includes an electrical steel sheet base material and an insulating film located on the surface of the electrical steel sheet base material, wherein the insulating film includes phosphate, silica, nitrate, and an oxidizing agent, Silica includes a solid content of 50 to 400 parts by weight based on 100 parts by weight of phosphate, the mixing ratio of the silica solid content to the phosphate solid content is 0.3 to 3.9, and the oxidizing agent has a solid content of 0.5 to 10.0 parts by weight based on 100 parts by weight of the phosphate. May include wealth.
본 발명의 또 다른 실시예에 따른, 방향성 전기강판의 제조 방법은 전기강판 기재를 준비하는 단계, 상기 전기강판 기재의 표면에 절연 코팅 조성물을 도포하는 단계, 및 상기 절연 코팅 조성물을 경화시키는 단계를 포함하며, 상기 절연 코팅 조성물은 인산염, 실리카, 질산염, 및 산화제를 포함하고, 상기 실리카는 인산염 100 중량부를 기준으로, 고형분 50 내지 400 중량부를 포함하고 상기 인산염 고형분에 대한 상기 실리카 고형분의 배합비는 0.3 내지 3.9 이고 상기 산화제는 상기 인산염 100 중량부를 기준으로, 고형분 0.5 내지 10.0 중량부를 포함하며, 상기 절연 코팅 조성물을 경화시키는 단계는 800 내지 900 ℃ 범위에서 30 초 내지 180초 범위로 수행될 수 있다.According to another embodiment of the present invention, a method for manufacturing a grain-oriented electrical steel sheet includes preparing an electrical steel sheet base material, applying an insulating coating composition to the surface of the electrical steel sheet base material, and curing the insulating coating composition. The insulating coating composition includes phosphate, silica, nitrate, and an oxidizing agent, the silica includes 50 to 400 parts by weight of solid content based on 100 parts by weight of phosphate, and the mixing ratio of the silica solid content to the phosphate solid content is 0.3. to 3.9, and the oxidizing agent includes a solid content of 0.5 to 10.0 parts by weight based on 100 parts by weight of the phosphate, and the step of curing the insulating coating composition may be performed in the range of 800 to 900 ° C. for 30 seconds to 180 seconds.
일 실시예에서, 상기 전기강판 기재의 표면에 절연 코팅 조성물을 도포하는 단계는 인산염 및 실리카를 투입하여 혼용하는 단계, 혼용된 용액에 질산염을 투입하는 단계, 및 이후, 산화제를 첨가하는 단계를 포함할 수 있다. 일 실시예에서, 전기강판 기재를 준비하는 단계는 강 슬라브를 준비하는 단계, 상기 강 슬라브를 가열하는 단계, 가열된 상기 강 슬라브를 열간 압연하여 열연 강판을 제조하는 단계, 상기 열연 강판을 냉간 압연시켜 냉연 강판을 제조하는 단계, 냉연판을 1차 재결정 소둔하는 단계, 1차 재결정 소둔된 강판 상에 소둔 분리제를 도포하는 단계, 및 2차 재결정 소둔을 수행하는 단계를 포함할 수 있다.In one embodiment, the step of applying an insulating coating composition to the surface of the electrical steel substrate includes adding and mixing phosphate and silica, adding nitrate to the mixed solution, and then adding an oxidizing agent. can do. In one embodiment, the step of preparing an electrical steel sheet base includes preparing a steel slab, heating the steel slab, hot rolling the heated steel slab to produce a hot rolled steel sheet, and cold rolling the hot rolled steel sheet. It may include manufacturing a cold rolled steel sheet, performing primary recrystallization annealing on the cold rolled sheet, applying an annealing separator on the primary recrystallization annealed steel sheet, and performing secondary recrystallization annealing.
일 실시예에서, 상기 1차 재결정 소둔된 강판 상에 소둔 분리제를 도포하는 단계는 상기 소둔 분리제를 1 내지 5 g/m2 범위로 도포하는 단계를 포함할 수 있다. 일 실시예에서, 상기 2차 재결정 소둔하는 단계는 균열 단계 및 승온 단계를 포함하며, 상기 균열 단계는 650 내지 750 ℃ 범위에서 수행되고, 상기 승온 단계는 1,100 내지 1,250 ℃ 범위에서 수행될 수 있다.In one embodiment, the step of applying an annealing separator on the primary recrystallization annealed steel sheet may include applying the annealing separator in a range of 1 to 5 g/m 2 . In one embodiment, the secondary recrystallization annealing step includes a cracking step and a temperature raising step, the cracking step may be performed in the range of 650 to 750 ° C., and the temperature raising step may be performed in the range of 1,100 to 1,250 ° C.
일 실시예에서, 상기 승온 단계는 10 내지 20 ℃/hr 범위의 승온 속도로 수행될 수 있다. 일 실시예에서, 상기 균열 단계는 수소 가스, 질소 가스, 비활성 기체 가스 중 2 이상의 가스 분위기에서 수행될 수 있다. 일 실시예에서 상기 승온 단계는 수소 분위기에서 수행될 수 있다.In one embodiment, the temperature increasing step may be performed at a temperature increasing rate in the range of 10 to 20 °C/hr. In one embodiment, the cracking step may be performed in an atmosphere of two or more gases selected from hydrogen gas, nitrogen gas, and inert gas gas. In one embodiment, the temperature raising step may be performed in a hydrogen atmosphere.
본 발명의 일 실시예에 따른 절연 피막 조성물은 방향성 전기강판에 인산염의 수소기 제거를 위한 산화제를 첨가함으로써, 고온 다습한 환경에서 내구성이 우수하고 극한의 내식성을 가지며, SRA와 같은 가공성이 매우 높은 온도에서 내열성이 우수한 방향성 전기강판용 절연 피막 조성물을 제공한다.The insulating coating composition according to an embodiment of the present invention has excellent durability and extreme corrosion resistance in a high temperature and high humidity environment by adding an oxidizing agent to remove the hydrogen group of phosphate in the grain-oriented electrical steel sheet, and has very high processability such as SRA. An insulating coating composition for grain-oriented electrical steel sheets with excellent heat resistance at high temperatures is provided.
본 발명의 다른 실시예에 따른, 방향성 전기강판은 전술한 절연 피막 조성물로 코팅된 방향성 전기강판을 제공할 수 있다.According to another embodiment of the present invention, a grain-oriented electrical steel sheet coated with the above-described insulating coating composition can be provided.
본 발명의 또 다른 실시예에 따른, 전술한 이점을 갖는 방향성 전기강판을 제조하는 방법을 제공할 수 있다.According to another embodiment of the present invention, a method for manufacturing a grain-oriented electrical steel sheet having the above-mentioned advantages can be provided.
제1, 제2 및 제3 등의 용어들은 다양한 부분, 성분, 영역, 층 및/또는 섹션들을 설명하기 위해 사용되나 이들에 한정되지 않는다. 이들 용어들은 어느 부분, 성분, 영역, 층 또는 섹션을 다른 부분, 성분, 영역, 층 또는 섹션과 구별하기 위해서만 사용된다. 따라서, 이하에서 서술하는 제1 부분, 성분, 영역, 층 또는 섹션은 본 발명의 범위를 벗어나지 않는 범위 내에서 제2 부분, 성분, 영역, 층 또는 섹션으로 언급될 수 있다.Terms such as first, second, and third are used to describe, but are not limited to, various parts, components, regions, layers, and/or sections. These terms are used only to distinguish one portion, component, region, layer or section from another portion, component, region, layer or section. Accordingly, the first part, component, region, layer or section described below may be referred to as the second part, component, region, layer or section without departing from the scope of the present invention.
여기서 사용되는 전문 용어는 단지 특정 실시예를 언급하기 위한 것이며, 본 발명을 한정하는 것을 의도하지 않는다. 여기서 사용되는 단수 형태들은 문구들이 이와 명백히 반대의 의미를 나타내지 않는 한 복수 형태들도 포함한다. 명세서에서 사용되는 “포함하는”의 의미는 특정 특성, 영역, 정수, 단계, 동작, 요소 및/또는 성분을 구체화하며, 다른 특성, 영역, 정수, 단계, 동작, 요소 및/또는 성분의 존재나 부가를 제외시키는 것은 아니다.The terminology used herein is only intended to refer to specific embodiments and is not intended to limit the invention. As used herein, singular forms include plural forms unless phrases clearly indicate the contrary. As used in the specification, “comprising” means specifying a particular characteristic, area, integer, step, operation, element and/or ingredient, and the presence or presence of another characteristic, area, integer, step, operation, element and/or ingredient. This does not exclude addition.
어느 부분이 다른 부분의 "위에" 또는 "상에" 있다고 언급하는 경우, 이는 바로 다른 부분의 위에 또는 상에 있을 수 있거나 그 사이에 다른 부분이 수반될 수 있다. 대조적으로 어느 부분이 다른 부분의 "바로 위에" 있다고 언급하는 경우, 그 사이에 다른 부분이 개재되지 않는다.When a part is referred to as being “on” or “on” another part, it may be directly on or on the other part or may be accompanied by another part in between. In contrast, when a part is said to be "directly on top" of another part, there is no intervening part between them.
다르게 정의하지는 않았지만, 여기에 사용되는 기술용어 및 과학용어를 포함하는 모든 용어들은 본 발명이 속하는 기술분야에서 통상의 지식을 가진 자가 일반적으로 이해하는 의미와 동일한 의미를 가진다. 보통 사용되는 사전에 정의된 용어들은 관련기술문헌과 현재 개시된 내용에 부합하는 의미를 가지는 것으로 추가 해석되고, 정의되지 않는 한 이상적이거나 매우 공식적인 의미로 해석되지 않는다.Although not defined differently, all terms including technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art in the technical field to which the present invention pertains. Terms defined in commonly used dictionaries are further interpreted as having meanings consistent with related technical literature and currently disclosed content, and are not interpreted in ideal or very formal meanings unless defined.
또한, 특별히 언급하지 않는 한 %는 중량%를 의미하며, 1ppm 은 0.0001중량%이다.Additionally, unless specifically stated, % means weight%, and 1ppm is 0.0001% by weight.
본 발명의 일 실시예에서 추가 원소를 더 포함하는 것의 의미는 추가 원소의 추가량 만큼 잔부인 철(Fe)을 대체하여 포함하는 것을 의미한다.In one embodiment of the present invention, further including an additional element means replacing the remaining iron (Fe) by the amount of the additional element.
이하, 본 발명의 실시예에 대하여 본 발명이 속하는 기술분야에서 통상의 지식을 가진 자가 용이하게 실시할 수 있도록 상세히 설명한다. 그러나 본 발명은 여러 가지 상이한 형태로 구현될 수 있으며 여기에서 설명하는 실시예에 한정되지 않는다.Hereinafter, embodiments of the present invention will be described in detail so that those skilled in the art can easily implement the present invention. However, the present invention may be implemented in many different forms and is not limited to the embodiments described herein.
본 발명의 일 실시예에 따른, 방향성 전기강판용 절연 피막 조성물은 인산염, 실리카, 질산염, 및 산화제를 포함할 수 있다. 상기 인산염은 금속 인산염으로, M(H2PO4) 또는 M(HPO4)를 만족할 수 있다. 상기 M은 Mg, Al, Zn, Ca 또는 이들의 조합을 포함할 수 있다. 예를 들어, 상기 M은 Mg 및 Al을 포함하는 인산염일 수 있다.According to an embodiment of the present invention, the insulating coating composition for a grain-oriented electrical steel sheet may include phosphate, silica, nitrate, and an oxidizing agent. The phosphate is a metal phosphate and may satisfy M(H 2 PO 4 ) or M(HPO 4 ). The M may include Mg, Al, Zn, Ca, or a combination thereof. For example, M may be a phosphate containing Mg and Al.
상기 실리카는 강판에 장력을 부여하여 철손을 저감하기 위해 필요한 성분이다. 또한, 상기 인산염은 실리카의 바인더로서 작용함으로써, 코팅의 성막성을 향상시키고, 피막 밀착성을 향상시키는 구성이다. 일 실시예에서, 상기 실리카는 염기성 또는 산성의 물질일 수 있다.The silica is a necessary ingredient to reduce iron loss by applying tension to the steel sheet. In addition, the phosphate acts as a binder for silica, thereby improving the film forming properties of the coating and improving film adhesion. In one embodiment, the silica may be a basic or acidic material.
일 실시예에서, 상기 실리카는 인산염 100 중량부를 기준으로 고형분 50 내지 400 중량부를 포함할 수 있다. 구체적으로, 상기 실리카는 상기 인산염 100 중량부를 기준으로 80 내지 200 중량부, 더욱 구체적으로 135 내지 180 중량부, 더욱 구체적으로 145 내지 160 중량부를 포함할 수 있다.In one embodiment, the silica may include 50 to 400 parts by weight of solid content based on 100 parts by weight of phosphate. Specifically, the silica may include 80 to 200 parts by weight, more specifically 135 to 180 parts by weight, and more specifically 145 to 160 parts by weight based on 100 parts by weight of the phosphate.
상기 실리카의 범위가 상한 값을 벗어나는 경우, 스티키성 또는 용액 안정성에 있어서 열위한 효과를 갖는 것을 확인할 수 있다. 상기 실리카의 범위가 하한 값을 벗어나는 경우, 강판에 장력 부여 효과가 미비한 문제가 있다.If the range of silica is outside the upper limit, it can be confirmed that it has a poor effect in stickiness or solution stability. If the range of silica is outside the lower limit, there is a problem that the effect of providing tension to the steel sheet is insufficient.
일 실시예에서, 상기 실리카는 평균 입경이 5 내지 20 nm 범위 일 수 있다. 상기 실리카의 평균 입경이 상기 범위의 상한 값을 벗어나는 경우, 단위질량당 표면적이 작아져 축합 반응속도가 느려지고, 반응 속도를 높이기 위해 열처리 온도를 높여야 하기 때문에 비경제적인 문제가 있다. 상기 실리카의 평균 입경이 상기 범위의 하한 값을 벗어나는 경우, 축합 반응속도가 빨라 응집 현상이 발생되며 표면에 색상 편차 결함을 유발하는 문제가 있다. In one embodiment, the silica may have an average particle diameter ranging from 5 to 20 nm. If the average particle diameter of the silica is outside the upper limit of the above range, the surface area per unit mass becomes small, which slows the condensation reaction rate, and there is an uneconomical problem because the heat treatment temperature must be increased to increase the reaction rate. If the average particle diameter of the silica is outside the lower limit of the above range, the condensation reaction rate is fast, agglomeration occurs, and there is a problem of causing color deviation defects on the surface.
일 실시예에서, 상기 실리카는 평균 입경이 상이한 적어도 하나의 나노 입자로 구성될 수 있다. 구체적으로, 상기 실리카는 우수한 피막 특성을 갖는 절연 피막을 형성하기 위해 평균 입경이 상이한 적어도 하나 이상의 실리카 나노 입자를 혼합하여 사용할 수도 있다.In one embodiment, the silica may be composed of at least one nanoparticle having a different average particle diameter. Specifically, the silica may be used by mixing at least one or more silica nanoparticles with different average particle diameters to form an insulating film with excellent film properties.
일 실시예에서, 상기 인산염 고형분에 대한 상기 실리카 고형분의 배합비는 0.3 내지 3.9 일 수 있다. 구체적으로, 상기 배합비는 0.5 내지 2.0 일 수 있다. 상기 배합비로 상기 실리카 및 상기 인산염이 배합됨에 따라, 전기강판 제조 시, 모재와의 접착력이 우수하고, 내열성, 내후성, 및 내식성이 우수한 이점이 발현될 수 있다.In one embodiment, the mixing ratio of the silica solid content to the phosphate solid content may be 0.3 to 3.9. Specifically, the mixing ratio may be 0.5 to 2.0. As the silica and the phosphate are mixed in the above mixing ratio, the advantages of excellent adhesion to the base material, heat resistance, weather resistance, and corrosion resistance can be realized when manufacturing electrical steel sheets.
상기 배합비에 있어서, 상기 인산염의 비율이 과도하게 많은 경우, 고온 다습한 환경에서 내구성이 저하되는 문제가 있다. 상기 실리카의 비율이 과도하게 높은 경우, 모재와의 접착력이 저하되는 문제가 있다.In the above mixing ratio, if the proportion of the phosphate is excessively high, there is a problem that durability is reduced in a high temperature and high humidity environment. If the ratio of silica is excessively high, there is a problem that adhesion to the base material is reduced.
상기 질산염은 내식성 및 내후성에 기인하는 역할을 수행하는 구성일 수있다. 일 실시예에서, 상기 질산염은 질산알루미늄(Al(NO3)3), 질산코발트(Co(NO3)2), 질산칼슘(Ca(NO3)2), 질산스트론튬(Sr(NO3)2), 질산아연(Zn(NO3)2), 질산망간(Mn(NO3)2), 질산마그네슘(Mg(NO3)2), 및 질산은(AgNO3) 중 어느 하나일 수 있다.The nitrate may be a component that plays a role in corrosion resistance and weather resistance. In one embodiment, the nitrate is aluminum nitrate (Al(NO 3 ) 3 ), cobalt nitrate (Co(NO 3 ) 2 ), calcium nitrate (Ca(NO 3 ) 2 ), and strontium nitrate (Sr(NO 3 ) 2 ), zinc nitrate (Zn(NO 3 ) 2 ), manganese nitrate (Mn(NO 3 ) 2 ), magnesium nitrate (Mg(NO 3 ) 2 ), and silver nitrate (AgNO 3 ).
일 실시예에서, 상기 질산염은 상기 인산염 100 중량부를 기준으로, 고형분 5 내지 100 중량부를 포함할 수 있다. 구체적으로, 상기 질산염은 상기 인산염 100 중량부를 기준으로, 고형분 15 내지 80 중량부, 더욱 구체적으로, 고형분 20 내지 60 중량부, 더욱 구체적으로, 고형분 22 내지 51 중량부, 더욱 구체적으로, 22 내지 28 중량부를 포함할 수 있다.In one embodiment, the nitrate may include 5 to 100 parts by weight of solid content based on 100 parts by weight of the phosphate. Specifically, the nitrate has a solid content of 15 to 80 parts by weight, more specifically, a solid content of 20 to 60 parts by weight, more specifically, a solid content of 22 to 51 parts by weight, and more specifically, 22 to 28 parts by weight, based on 100 parts by weight of the phosphate. It may include weight parts.
상기 질산염의 함량이 상기 범위의 상한 값을 벗어나는 경우, 화재의 위험이 있다. 상기 질산염의 함량이 상기 범위의 하한 값을 벗어나는 경우, 내후성의 문제가 있다.If the nitrate content is outside the upper limit of the above range, there is a risk of fire. If the nitrate content is outside the lower limit of the above range, there is a problem with weather resistance.
상기 산화제는 M(H2PO4) 또는 M(HPO4)과 같은 인산염에서 수소기(H)를 제거하기 위한 첨가제 역할을 수행할 수 있다. 상기 산화제는 상기 인산염에서 상기 수소기를 제거함으로써, 스티키(Sticky)한 성질을 갖는 M(H2PO4) 또는 M(HPO4)와 같은 인산염에서 H를 제거하여 스티키한 성질을 갖지 않는 M(PO4)로 반응시키는 역할을 할 수 있다.The oxidizing agent may serve as an additive for removing hydrogen groups (H) from phosphates such as M(H 2 PO 4 ) or M(HPO 4 ). The oxidizing agent removes H from phosphates such as M(H 2 PO 4 ) or M(HPO 4 ), which have sticky properties, by removing the hydrogen group from the phosphate, thereby forming M(PO), which does not have sticky properties. 4 ) can play a role in causing the reaction.
일 실시예에서, 상기 산화제는 HClO4, NaClO, NaClO4, KMnO4, NaIO4, OsO4, H2O2, Ca(ClO)2 중 적어도 어느 하나를 포함할 수 있다. 상기 산화제는 전술한 바와 같이, 인산염을 산화시켜 수소기를 제거하는 것을 포함할 수 있다.In one embodiment, the oxidizing agent may include at least one of HClO 4 , NaClO, NaClO 4 , KMnO 4 , NaIO 4 , OsO 4 , H 2 O 2 , and Ca(ClO) 2 . As described above, the oxidizing agent may include oxidizing phosphate to remove a hydrogen group.
일 실시예에서, 상기 산화제는 상기 인산염 100 중량부를 기준으로, 고형분 0.5 내지 10.0 중량부를 포함할 수 있다. 상기 산화제는 상기 인산염 100 중량부를 기준으로 0.8 내지 5.0 중량부, 더욱 구체적으로, 1.0 내지 3.0 중량부를 포함할 수 있다. 상기 산화제를 전술한 범위로 포함함으로써, 상기 인산염에 의해 발현되는 스티키성을 저하시키는 이점이 있다.In one embodiment, the oxidizing agent may include 0.5 to 10.0 parts by weight of solid content based on 100 parts by weight of the phosphate. The oxidizing agent may include 0.8 to 5.0 parts by weight, more specifically, 1.0 to 3.0 parts by weight, based on 100 parts by weight of the phosphate. By including the oxidizing agent in the above-mentioned range, there is an advantage in reducing the stickiness expressed by the phosphate.
상기 산화제의 함량이 상기 범위의 상한 값을 벗어나는 경우, 내스티키성과 용액 안정성에서 열위한 효과를 가질 수 있다. 상기 산화제의 함량이 상기 범위의 하한 값을 벗어나는 경우, 산화제 첨가에 따른 스티키성을 저하시키는 이점이 발현되지 않는 문제가 있다.If the content of the oxidizing agent is outside the upper limit of the above range, it may have a poor effect on stickiness resistance and solution stability. If the content of the oxidizing agent is outside the lower limit of the above range, there is a problem in that the advantage of reducing stickiness due to the addition of the oxidizing agent is not realized.
일 실시예에서, 상기 실리카는 산성 물질일 수 있다. 상기 실리카로 염기성 물질을 사용할 경우, 상기 인산염과 상기 질산염이 안정적이지 못하고 겔화되는 현상이 발생하는 문제가 있다.In one embodiment, the silica may be an acidic material. When using a basic material as the silica, there is a problem in that the phosphate and nitrate are not stable and gelation occurs.
본 발명의 다른 실시예에 따른, 방향성 전기강판은 전기강판 기재 및 상기 전기강판 기재 표면 상에 위치하는 절연 피막을 포함한다. 상기 절연 피막은 인산염, 실리카, 질산염, 및 산화제를 포함하는 것으로, 상기 인산염, 실리카, 질산염, 및 산화제에 대한 상세한 설명은 전술하여 설명한 절연 피막 조성물의 내용과 모순되지 않는 범위에서 동일하다.According to another embodiment of the present invention, a grain-oriented electrical steel sheet includes an electrical steel sheet base material and an insulating film located on the surface of the electrical steel sheet base material. The insulating coating includes phosphate, silica, nitrate, and an oxidizing agent, and the detailed description of the phosphate, silica, nitrate, and oxidizing agent is the same as the content of the insulating coating composition described above to the extent that it does not contradict.
본 발명의 또 다른 실시예에 따른, 방향성 전기강판의 제조 방법은 전기강판 기재를 준비하는 단계, 상기 전기강판 기재의 표면에 절연 코팅 조성물을 도포하는 단계, 및 상기 절연 코팅 조성물을 경화시키는 단계를 포함한다. According to another embodiment of the present invention, a method for manufacturing a grain-oriented electrical steel sheet includes preparing an electrical steel sheet base material, applying an insulating coating composition to the surface of the electrical steel sheet base material, and curing the insulating coating composition. Includes.
상기 전기강판 기재를 준비하는 단계는 강 슬라브를 준비하는 단계, 상기 강 슬라브를 가열하는 단계, 가열된 상기 강 슬라브를 열간 압연하여 열연 강판을 제조하는 단계, 상기 열연 강판을 냉간 압연시켜 냉연 강판을 제조하는 단계, 냉연판을 1차 재결정 소둔하는 단계, 1차 재결정 소둔된 강판 상에 소둔 분리제를 도포하는 단계 및 2차 재결정 소둔을 수행하는 단계를 포함할 수 있다.The step of preparing the electrical steel sheet base includes preparing a steel slab, heating the steel slab, hot rolling the heated steel slab to produce a hot rolled steel sheet, and cold rolling the hot rolled steel sheet to produce a cold rolled steel sheet. It may include manufacturing, primary recrystallization annealing of the cold rolled sheet, applying an annealing separator on the primary recrystallization annealing, and performing secondary recrystallization annealing.
상기 강 슬라브를 가열하는 단계는 사기 강 슬라브를 1,300 ℃ 이하의 온도로 가열할 수 있다. 전술한 온도 범위로 상기 강 슬라브를 가열하는 경우, 슬라브의 주상정 조지기 조대하게 성장되는 것을 방지하여 열간압연 공정에서 판의 크랙이 발생되는 것을 방지할 수 있다. 구체적으로 상기 강 슬라브를 가열하는 단계는 1,050 내지 1,300 ℃의 온도로 가열할 수 있다.In the step of heating the steel slab, the steel slab may be heated to a temperature of 1,300° C. or lower. When heating the steel slab to the above-mentioned temperature range, coarse growth of the columnar crystals of the slab can be prevented, thereby preventing cracks in the plate from occurring during the hot rolling process. Specifically, the step of heating the steel slab may be heated to a temperature of 1,050 to 1,300 °C.
이후, 가열된 상기 강 슬라브를 열간 압연하여 열연 강판을 제조할 수 있다. 상기 열간 압연 온도는 제한되지 않으며, 일 실시예로 950 ℃ 이하의 온도에서 열간 압연을 종료할 수 있다.Thereafter, the heated steel slab can be hot rolled to produce a hot rolled steel sheet. The hot rolling temperature is not limited, and in one embodiment, hot rolling may be completed at a temperature of 950° C. or lower.
일 실시예에서, 상기 열연 강판을 제조하는 단계 이후, 상기 열연 강판을 소둔하는 단계를 수행할 수 있다. 상기 열연 강판을 소둔하는 단계는 열연 강판의 불균일한 미세조직과 석출물을 균질화 할 수 있다. 구체적으로, 상기 열연 강판을 소둔하는 단계는 800 내지 1,300 ℃의 온도 범위에서 수행될 수 있다.In one embodiment, after manufacturing the hot rolled steel sheet, annealing the hot rolled steel sheet may be performed. The step of annealing the hot rolled steel sheet can homogenize the uneven microstructure and precipitates of the hot rolled steel sheet. Specifically, the step of annealing the hot rolled steel sheet may be performed at a temperature range of 800 to 1,300 °C.
이후, 상기 열연 강판을 냉간 압연시켜 냉연 강판을 제조하는 단계를 수행할 수 있다. 상기 냉간 압연하는 단계는 1회의 냉간 압연 또는 중간 소둔을 포함한 2회 이상의 냉간 압연을 실시할 수 있다.Thereafter, a step of manufacturing a cold rolled steel sheet may be performed by cold rolling the hot rolled steel sheet. The cold rolling step may include one cold rolling or two or more cold rollings including intermediate annealing.
이후, 냉연 강판을 1차 재결정 소둔하는 단계를 수행할 수 있다. 이 때, 상기 1차 재결정 소둔하는 단계는 탈탄 단계 및 질화 단계를 포함할 수 있다. 상기 탈탄 단계 및 상기 질화 단계는 순서와 무관하게 수행할 수 있다. 예를 들어, 탈탄 단계 이후 질화 단계를 수행하거나, 침질 단계 이후 탈탄 단계를 수행할 수 있다. Thereafter, a step of primary recrystallization annealing of the cold rolled steel sheet may be performed. At this time, the primary recrystallization annealing step may include a decarburization step and a nitriding step. The decarburization step and the nitridation step may be performed in any order. For example, a nitriding step may be performed after a decarburization step, or a decarburization step may be performed after a nitriding step.
일 실시예에서, 냉간 압연을 통해 얻어진 냉연 강판을 탈탄 소둔 및 질화 처리를 동시에 실시하여 1차 재결정시키는 단계를 포함할 수 있다. 구체적으로, 탈탄 단계 및 침질 단계를 동시에 수행할 수 있다. 상기 질화 단계는 강판 내 질화를 위한 것으로서, 강판에 질소 이온을 도입하는 단계로서, 결정 성장 억제제인 (Al, Si, Mn)N 또는 AlN과 같은 석출물을 석출하는 단계이다. 상기 질화 단계를 거쳐 방향성 전기강판의 질소가 0.01 % 이하가 되도록 질화할 수 있다.In one embodiment, it may include the step of primary recrystallization by simultaneously performing decarburization annealing and nitriding treatment on a cold rolled steel sheet obtained through cold rolling. Specifically, the decarburization step and the sieving step can be performed simultaneously. The nitriding step is for nitriding the steel sheet, is a step of introducing nitrogen ions into the steel sheet, and is a step of precipitating precipitates such as (Al, Si, Mn)N or AlN, which are crystal growth inhibitors. Through the above nitriding step, the grain-oriented electrical steel sheet can be nitrided so that the nitrogen content is 0.01% or less.
1차 재결정 소둔하는 단계에 있어서, 소둔 온도는 800 내지 950 ℃ 범위내에서 열처리할 수 있다. 상기 소둔 온도의 범위가 상한 값을 벗어나는 경우, 재결정립들이 조대하게 성장하여 결정 성장 구동력이 저하됨에 따라, 안정된 2차 재결정이 형성되지 못하는 문제가 있다. 상기 소둔 온도의 범위가 하한 값을 벗어나는 경우, 탈탄 시 과도하게 시간이 소요되는 문제가 있다.In the primary recrystallization annealing step, the annealing temperature may be within the range of 800 to 950°C. When the annealing temperature range is outside the upper limit, the recrystallized grains grow coarsely and the driving force for crystal growth decreases, resulting in the problem that stable secondary recrystallization cannot be formed. If the annealing temperature range exceeds the lower limit, there is a problem that excessive time is taken during decarburization.
1차 재결정 소둔하는 단계는 질소, 수소, 및 이들의 혼합 가스 분위기에서 수행될 수 있다. 예를 들어, 상기 가스 분위기는 암모니아 가스 분위기일 수 있다. 상기 가스 분위기는 습윤 분위기 또는 건조 분위기에서 행해질 수 있다.The primary recrystallization annealing step may be performed in a nitrogen, hydrogen, or mixed gas atmosphere. For example, the gas atmosphere may be an ammonia gas atmosphere. The gas atmosphere may be performed in a wet atmosphere or a dry atmosphere.
1차 재결정 소둔하는 단계 이후, 강판에 소둔 분리제를 도포할 수 있다. 예를 들어, 상기 소둔 분리제로서, MgO를 주성분으로 하는 소둔 분리제를 사용할 수 있다. 일 실시예에서, 상기 소둔 분리제를 도포하는 단계에서 상기 소둔 분리제의 도포량은 1 내지 5 g/m2 범위로 수행될 수 있다.After the first recrystallization annealing step, an annealing separator can be applied to the steel sheet. For example, as the annealing separator, an annealing separator containing MgO as a main component can be used. In one embodiment, in the step of applying the annealing separator, the application amount of the annealing separator may be in the range of 1 to 5 g/m 2 .
상기 소둔 분리제의 도포량이 상기 범위의 상한 값을 벗어나는 경우, 2차 재결정에 영향을 주는 문제가 있다. 상기 소둔 분리제의 도포량이 상기 범위의 하한 값을 벗어나는 경우, 피막의 형성이 원활하게 형성되기 어려운 문제가 있다.If the application amount of the annealing separator is outside the upper limit of the above range, there is a problem affecting secondary recrystallization. If the application amount of the annealing separator is outside the lower limit of the above range, there is a problem in that it is difficult to form a film smoothly.
2차 재결정 소둔을 수행하는 단계는 2차 재결정에 의한 {110}<001> 집합조직 형성, 1차 재결정 소둔 시 형성된 산화층과 MgO의 반응에 의한 유리질 피막형성으로 절연성 부여, 자기특성을 저해하는 불순물을 제거하는 것이다.The steps for performing secondary recrystallization annealing include forming a {110}<001> texture by secondary recrystallization, forming a glassy film by reacting MgO with the oxide layer formed during primary recrystallization, providing insulation, and removing impurities that impede magnetic properties. is to remove.
일 실시예에서, 상기 2차 재결정 소둔하는 단계는 균열 단계 및 승온 단계를 포함할 수 있다. 상기 균열 단계는 650 내지 750 ℃ 범위에서 수행되고, 상기 승온 단계는 1,100 내지 1,250 ℃ 범위에서 수행될 수 있다. 상기 온도 범위를 벗어나는 경우, 적절한 피막이 형성되기 어려운 문제가 있다.In one embodiment, the secondary recrystallization annealing step may include a cracking step and a temperature raising step. The cracking step may be performed in the range of 650 to 750 °C, and the temperature raising step may be performed in the range of 1,100 to 1,250 °C. If the temperature is outside the above range, it is difficult to form an appropriate film.
일 실시예에서, 상기 승온 단계는 10 내지 20 ℃/hr 범위의 승온 속도로 수행될 수 있다. 구체적으로, 상기 승온 속도는 13 내지 17 ℃/hr 범위로 수행될 수 있다.In one embodiment, the temperature increasing step may be performed at a temperature increasing rate in the range of 10 to 20 °C/hr. Specifically, the temperature increase rate may be performed in the range of 13 to 17 °C/hr.
상기 승온 속도가 상기 범위의 상한 값을 벗어나는 경우, 인산염의 분해로코팅막이 분해되는 문제가 있다. 상기 승온 속도가 상기 범위의 하한 값을 벗어나는 경우, 실리카의 미경화로 내식성 및 내후성이 열위한 문제가 있다. If the temperature increase rate is outside the upper limit of the above range, there is a problem that the coating film is decomposed due to decomposition of phosphate. If the temperature increase rate is outside the lower limit of the above range, there is a problem of poor corrosion resistance and weather resistance due to non-curing of the silica.
일 실시예에서, 상기 균열 단계는 수소 가스, 질소 가스, 비활성 기체 가스 중 적어도 2 이상의 가스 분위기에서 수행될 수 있다. 일 실시예에서, 상기 승온 단계는 수소 가스 분위기에서 수행될 수 있다. 구체적으로, 2차 재결정 소둔의 방법으로는 2차 재결정이 일어나기 전의 승온 단계에서는 질소와 수소의 혼합가스로 유지하여 입자성장 억제제인 질화물을 보호함으로써 2차 재결정이 잘 발달할 수 있도록 하고, 2차 재결정이 완료된 후 균열 단계에서는 100% 수소분위기에서 장시간 유지하여 불순물을 제거한다.In one embodiment, the cracking step may be performed in an atmosphere of at least two of hydrogen gas, nitrogen gas, and inert gas gas. In one embodiment, the temperature raising step may be performed in a hydrogen gas atmosphere. Specifically, as a method of secondary recrystallization annealing, in the temperature increase stage before secondary recrystallization occurs, a mixed gas of nitrogen and hydrogen is maintained to protect nitride, which is a grain growth inhibitor, so that secondary recrystallization can develop well. After recrystallization is completed, in the cracking stage, impurities are removed by maintaining a 100% hydrogen atmosphere for a long time.
일 실시예에서, 상기 전기강판 기재의 표면에 절연 코팅 조성물을 도포하는 단계는 인산염 및 실리카을 투입하여 혼용하는 단계; 혼용된 용액에 질산염을 투입하는 단계; 및 이후, 산화제를 첨가하는 단계를 포함한다. 상기 인산염, 상기 실리카, 상기 질산염, 및 상기 산화제는 전술한 절연 코팅 조성물에서 설명한 내용과 모순되지 않는 범위에서 동일하다.In one embodiment, the step of applying an insulating coating composition to the surface of the electrical steel substrate includes adding and mixing phosphate and silica; Adding nitrate to the mixed solution; and then adding an oxidizing agent. The phosphate, the silica, the nitrate, and the oxidizing agent are the same as those described in the above-described insulating coating composition to the extent not inconsistent with the content.
일 실시예에서, 상기 절연 코팅물을 경화시키는 단계는 800 내지 900 ℃의 온도 범위에서 수행될 수 있다. 상기 온도 범위의 상한 값을 벗어나는 경우, 절연 피막의 내후성 및 내식성이 저하되는 문제가 있다. 상기 온도 범위의 하한 값을 벗어나는 경우, 실리카 졸의 경화가 발생하지 않아 내식성 및 내후성에 문제가 발생할 수 있다.In one embodiment, curing the insulating coating may be performed at a temperature range of 800 to 900 °C. If the temperature exceeds the upper limit of the above temperature range, there is a problem that the weather resistance and corrosion resistance of the insulating film deteriorate. If the temperature exceeds the lower limit of the above temperature range, curing of the silica sol does not occur, which may cause problems with corrosion resistance and weather resistance.
일 실시예에서, 상기 절연 코팅물을 경화시키는 단계는 30 내지 240 초의 시간 동안 수행될 수 있다. 구체적으로, 상기 시간은 45 내지 180 초의 시간 동안 수행될 수 있다.In one embodiment, curing the insulating coating may be performed for a period of 30 to 240 seconds. Specifically, the time may be performed for a period of 45 to 180 seconds.
상기 시간의 상한 값을 벗어나는 경우, 인산염이 분해되는 문제가 있다. 상기 시간의 하한 값을 벗어나는 경우, 미경화로 인해 내식성 및 내후성이 열위해지는 문제가 있다.If the time exceeds the upper limit, there is a problem that phosphate is decomposed. If the time exceeds the lower limit, there is a problem that corrosion resistance and weather resistance are deteriorated due to non-curing.
이하 본 발명의 구체적인 실시예를 기재한다. 그러나 하기 실시예는 본 발명의 구체적인 일 실시예일뿐 본 발명이 하기 실시예에 한정되는 것은 아니다.Hereinafter, specific examples of the present invention will be described. However, the following example is only a specific example of the present invention, and the present invention is not limited to the following example.
실험예 1 내지 8Experimental Examples 1 to 8
본 발명의 방향성 전기강판용 절연 피막 조성물을 제조하기 위해, 하기 표 1의 함량을 갖는 인산염 고형분이 67 % 혼용된 알루미늄 및 마그네슘 인산염 용액을 제조하고, 이후, 하기 표 1의 함량을 갖는 고형분 함량이 30 % 혼용된 콜로이달 실리카 용액을 투입하여 혼용하였다.In order to prepare the insulating coating composition for grain-oriented electrical steel sheets of the present invention, an aluminum and magnesium phosphate solution mixed with 67% phosphate solids having the content shown in Table 1 below was prepared, and then, the solid content having the content shown in Table 1 below was mixed to 30%. % mixed colloidal silica solution was added and mixed.
이후, 하기 표 1의 함량을 갖는 전환 코팅 물질에 해당하는 질산 알루미늄 또는 질산 마그네슘과 같은 고형분 함량이 50 % 혼용된 질산염 용액을 투입하고, 이후, 하기 표 1의 함량을 갖는 HClO4, NaClO, 및 NaClO4와 같이 고형분 함량이 50 % 혼용된 산화제를 첨가하여 하기 표 1과 같은 조성의 절연피막 조성물 용액을 제조하였다. 제조된 상기 절연피막 조성물을 MgO가 처리된 강판 상에 상기 용액을 도포한다. 이후, 700 내지 950 ℃ 사이에서 30 내지 240 초 동안 건조시킨 후, 스키티성, 내후성, 내열성, 내식성, 용액 안정성을 평가하였다.Then, a nitrate solution mixed with a 50% solid content such as aluminum nitrate or magnesium nitrate corresponding to the conversion coating material with the content in Table 1 below was added, and then HClO 4 , NaClO, and NaClO with the content in Table 1 below were added. An insulating coating composition solution having the composition shown in Table 1 below was prepared by adding an oxidizing agent mixed with a solid content of 50%, such as NaClO 4 . The solution of the prepared insulating coating composition is applied onto the MgO-treated steel sheet. Afterwards, it was dried between 700 and 950°C for 30 to 240 seconds, and then the skid resistance, weather resistance, heat resistance, corrosion resistance, and solution stability were evaluated.
스키티성, 내후성, 내열성, 내식성, 용액 안정성의 경우, 하기와 같은 방법으로 평가하였다.Skit resistance, weather resistance, heat resistance, corrosion resistance, and solution stability were evaluated in the following manner.
<평가 방법><Evaluation method>
내스키티성 평가Skit resistance assessment
상기 내스티키성은 끈적임이 얼마나 없는지 평가하기 위한 것으로, 구의 직경 12.7mm, 가압하중 50N, 회 전속도 50rpm, 회전반경 15mm, 슬립거리 200m (Test 1)와 슬립거리에 따른 마모량 비교를 위하여 Test 1 과 동일한 하중과 회전속도에서 회전반경 10mm, 슬립거리를 10m 로 달리하여 실시 마찰계수로 스티키성을 평가한다. 이때, 마찰계수는 수직하중에 대한 마찰력(마찰력/수직하중) 으로 계산하였다. 마찰계수가 0.4 보다 낮아 양호한 경우, “OK”, 0.4 이상으로 불량인 경우, “NG”로 표시하였다.The above-mentioned stickiness is to evaluate the degree of stickiness. To compare the amount of wear according to the slip distance, Test 1 and the sphere diameter of 12.7mm, pressure load of 50N, rotation speed of 50rpm, rotation radius of 15mm, slip distance of 200m (Test 1), At the same load and rotation speed, the rotation radius is varied to 10 mm and the slip distance is varied to 10 m to evaluate the stickiness using the actual friction coefficient. At this time, the friction coefficient was calculated as the friction force against the vertical load (friction force/vertical load). If the friction coefficient was lower than 0.4 and good, it was marked as “OK”; if it was bad and higher than 0.4, it was marked as “NG.”
코팅성 평가Coating property evaluation
육안으로 평가하여 얼룩이 없어 양호한 경우, “OK”, 얼룩이 있어 불량인 경우, “NG”로 표시하였다.When evaluated visually, if the product was good because there were no stains, it was marked as “OK”; if it was defective because there were stains, it was marked as “NG.”
내후성 평가Weatherability evaluation
98 % 수분, 60 ℃, 72 시간의 조건에서 내후성을 평가한 것으로, 양호한 경우 “OK”, 불량인 경우 “NG”로 표시하였다.Weather resistance was evaluated under the conditions of 98% moisture, 60°C, and 72 hours. If it was good, it was marked as “OK,” and if it was bad, it was marked as “NG.”
내열성 평가Heat resistance evaluation
내열성 평가의 경우, 560 ℃, 수소 20 %, 질소 80 % 조건하에서 2 시간 가열하였다. 이후, CROSS-HATCH CUT 테스트를 통하여 5B 이상임을 확인하였다.In the case of heat resistance evaluation, it was heated at 560°C for 2 hours under the conditions of 20% hydrogen and 80% nitrogen. Afterwards, it was confirmed that it was 5B or more through the CROSS-HATCH CUT test.
상기 테스트의 결과가 5B 이상인 경우, 양호한 경우로 “OK”, 5B 미만인 경우, 불량인 경우로 “NG”로 표시하였다.If the result of the above test was 5B or more, it was marked as “OK” as good, and if it was less than 5B, it was marked as “NG” as bad.
내식성 평가Corrosion resistance evaluation
NaCl 5 %, 100 RH, 65 ℃, 8 시간 염수 분무 테스트를 실시하였다.A salt spray test was conducted with NaCl 5%, 100 RH, 65°C, 8 hours.
용액 안정성 평가Solution stability evaluation
10%NaOH 100ml, 2x2 CM 사이즈 코팅판을 용해한 다음 필터에 거른다. 용해되지 않고 가루로 존재하는 물질이 PO4이다. 필터에 남은 가루에 무게를 측정한 다음 가루가 존재하면 산화제에 의해 HPO4가 제거된 것으로 판명될 수 있다. Dissolve 100ml of 10%NaOH on a 2x2 CM coated plate and filter it. PO 4 is a substance that is not dissolved and exists as a powder. The powder remaining in the filter is weighed and if powder is present, it can be determined that HPO 4 has been removed by the oxidizing agent.
Cl 추척법: 10%NaOH 100 mL, 2x2 CM 사이즈 코팅을 용해한 다음 용액에 Cl 성분이 존재하면 Cl이 첨가된 것으로 볼 수 있다.Cl tracking method: Dissolve the 2x2 CM size coating in 100 mL of 10% NaOH. If Cl is present in the solution, it can be considered that Cl has been added.
구분division 조성Furtherance 특성characteristic 비고note
인산염phosphate 물water Silica
용액Silica
solution 		질산
마그
네슘nitric acid
marg
nesium 		질산
알루
미늄nitric acid
Aloo
Minium 		HClO4 HClO 4 NaClONaClO NaClO4 NaClO4 실리카/인산염Silica/Phosphate 내스티키성My sticky castle 내후성weather resistance 내식성corrosion resistance 용액
안정성solution
stability
[g][g] [g][g] [g][g] [g][g] [g][g] [g][g] [g][g] [g][g] --
실험예 1Experimental Example 1 5.65.6 5.45.4 7.47.4 00 22 00 00 00 1.321.32 NGNG NGNG NGNG OKOK 비교예Comparative example
실험예 2Experimental Example 2 5.65.6 5.45.4 7.47.4 00 22 0.10.1 00 00 1.321.32 OKOK OKOK OKOK OKOK 실시예Example
실험예 3Experimental Example 3 5.65.6 5.45.4 7.47.4 00 22 00 0.10.1 00 1.321.32 OKOK OKOK OKOK OKOK 실시예Example
실험예 4Experimental Example 4 5.65.6 5.45.4 7.47.4 00 22 00 00 0.10.1 1.321.32 OKOK OKOK OKOK OKOK 실시예Example
실험예 5Experimental Example 5 5.65.6 5.45.4 7.47.4 22 00 00 00 00 1.321.32 NGNG NGNG NGNG OKOK 비교예Comparative example
실험예 6Experimental Example 6 5.65.6 5.45.4 7.47.4 22 00 0.10.1 00 00 1.321.32 OKOK OKOK OKOK OKOK 실시예Example
실험예 7Experimental Example 7 5.65.6 5.45.4 7.47.4 22 00 00 0.10.1 00 1.321.32 OKOK OKOK OKOK OKOK 실시예Example
실험예 8Experimental Example 8 5.65.6 5.45.4 7.47.4 22 00 00 00 0.10.1 1.321.32 OKOK OKOK OKOK OKOK 실시예Example
상기 표 1을 살펴보면, 실험예 1와 실험예 2 내지 4를 비교하면, 산화제인 HClO4, NaClO, 또는 NaClO4와 같은 산화제를 추가로 첨가한 경우, 내스티키성, 내후성, 내식성, 및 용액 안정성이 양호한 것을 확인하였고, 상기 산화제를 첨가하지 않은 경우, 내스티키성, 내후성 및 내식성에서 불량한 것을 확인하였다.또한, 실험예 5 내지 실험예 8의 경우, 실험예 1 내지 실험예 4와 대비하여, 질산염으로 질산 알루미늄이 아닌 질산 마그네슘을 사용한 점에 있어서 차이가 있고, 상기 질산염으로 질산 알루미늄이 아닌 질산 마그네슘을 사용하더라도 동일한 효과를 갖는 것을 확인하였다.Looking at Table 1, comparing Experimental Example 1 and Experimental Examples 2 to 4, when an oxidizing agent such as HClO 4 , NaClO, or NaClO 4 is additionally added, stickiness resistance, weather resistance, corrosion resistance, and solution stability It was confirmed that this was good, and when the oxidizing agent was not added, it was confirmed that stickiness resistance, weather resistance, and corrosion resistance were poor. In addition, in the case of Experimental Examples 5 to 8, compared to Experimental Examples 1 to 4, There is a difference in that magnesium nitrate rather than aluminum nitrate was used as the nitrate, and it was confirmed that the same effect was obtained even when magnesium nitrate rather than aluminum nitrate was used as the nitrate.
구체적으로, 상기 산화제를 첨가함으로써, M(H2PO4) 또는 M(HPO4)와 같은 산화제로부터 하기 반응식에 의해 수소기가 제거될 수 있다.Specifically, by adding the oxidizing agent, hydrogen groups can be removed from the oxidizing agent such as M(H 2 PO 4 ) or M(HPO 4 ) according to the following reaction equation.
[반응식][Reaction formula]
2MX(HPO4)Y + NaClO → H2O + NaCl + MX(PO4)Y 2M ​ ​ ​ ​ ​ ​
상기 반응식에 의해, 상기 인산염에서 상기 수소기가 제거됨에 따라, 내스티커성이 양호하게 되는 것을 확인하였다.According to the above reaction formula, it was confirmed that as the hydrogen group was removed from the phosphate, the stickiness resistance improved.
실험예 9 내지 17Experimental Examples 9 to 17
하기 표 2는 방향성 전기강판용 절연 피막 조성물의 조성을 하기 표 2에 기재된 함량 범위로 제어하는 것과 질산염으로 질산 알루미늄을 사용하고, 산화제로 HClO4를 사용하는 점 외에 실험예 1 내지 8과 동일한 방법으로 상기 절연 피막 조성물을 제조하고, 이를 평가하였다. Table 2 below shows that the composition of the insulating coating composition for grain-oriented electrical steel sheets was controlled in the content range shown in Table 2 below, aluminum nitrate was used as the nitrate, and HClO 4 was used as the oxidizing agent, in the same manner as in Experimental Examples 1 to 8. An insulating coating composition was prepared and evaluated.
조성Furtherance 특성characteristic 비고note
인산염phosphate 물water SilicaSilica 질산
알루
미늄nitric acid
Aloo
Minium 		HClO4 HClO 4 실리카/
인산염Silica/
phosphate 		내스티키성My sticky castle 코팅성Coating properties 내후성weather resistance 내식성corrosion resistance 용액
안정성solution
stability
[g][g] [g][g] [g][g] [g][g] [g][g] --
실험예 9Experimental Example 9 33 33 88 22 0.10.1 2.672.67 OKOK OKOK OKOK OKOK OKOK 실시예Example
실험예 10Experimental Example 10 33 33 88 1One 0.10.1 2.672.67 OKOK OKOK OKOK OKOK OKOK 실시예Example
실험예 11Experimental Example 11 33 33 88 0.50.5 0.10.1 2.672.67 OKOK OKOK OKOK OKOK OKOK 실시예Example
실험예 12Experimental Example 12 33 33 88 22 0.50.5 2.672.67 OKOK OKOK OKOK OKOK NGNG 비교예Comparative example
실험예 13Experimental Example 13 33 33 1212 22 00 4.004.00 NGNG OKOK OKOK OKOK OKOK 비교예Comparative example
실험예 14Experimental Example 14 33 33 1212 22 0.10.1 4.004.00 NGNG OKOK OKOK OKOK OKOK 비교예Comparative example
실험예 15Experimental Example 15 33 33 1212 1One 0.10.1 4.004.00 NGNG OKOK OKOK OKOK OKOK 비교예Comparative example
실험예 16Experimental Example 16 33 33 1212 22 0.50.5 4.004.00 NGNG OKOK OKOK OKOK NGNG 비교예Comparative example
실험예 17Experimental Example 17 33 33 1212 1One 0.50.5 4.004.00 NGNG OKOK OKOK OKOK NGNG 비교예Comparative example
상기 표 2을 참조하면, 실험예 9 내지 12와 같이, 산화제인 HClO4를 첨가하였을 때, 상기 산화제를 첨가하지 않은 실험예 13과 대비하여 내스티키성을 가져 끈적임이 없는 것을 확인하였다. 또한, 상기 산화제를 과도하게 많이 첨가할 경우, 실험예 12와 같이 용액 안정성이 불량한 것을 확인하였다.또한, 상기 실험예 9 내지 11과 상기 실험예 14 내지 17를 비교하면, 실리카의 함량이 과도하게 많아, 인산염과 실리카 배합비가 본 발명의 목표한 배합비를 벗어나는 경우, 내스티키성 또는 용액 안정성에서 불량한 것을 확인하였다.Referring to Table 2, as in Experimental Examples 9 to 12, when HClO 4 as an oxidizing agent was added, it was confirmed that there was no stickiness due to stickiness compared to Experimental Example 13 in which the oxidizing agent was not added. In addition, when an excessive amount of the oxidizing agent was added, it was confirmed that the solution stability was poor as in Experimental Example 12. Additionally, when comparing Experimental Examples 9 to 11 and Experimental Examples 14 to 17, the content of silica was excessive. In many cases, when the mixing ratio of phosphate and silica exceeded the target mixing ratio of the present invention, it was confirmed that the sticky resistance or solution stability was poor.
실험예 18 내지 26Experimental Examples 18 to 26
실험예 18 내지 26은 방향성 전기강판용 절연 피막 조성물의 조성을 하기 표 3에 기재된 함량 범위로 제어하는 것 외에 실험예 1 내지 8과 동일한 방법으로 상기 절연 피막 조성물을 제조하고, 이를 평가하였다.In Experimental Examples 18 to 26, the insulating coating composition for grain-oriented electrical steel sheets was prepared and evaluated in the same manner as in Experimental Examples 1 to 8, except that the composition was controlled to the content range shown in Table 3 below.
구분division 조성Furtherance 특성characteristic 비고note
인산염phosphate 물water SilicaSilica 질산
알루
미늄nitric acid
Aloo
Minium 		HClO4 HClO 4 실리카/인산염Silica/Phosphate 내스티키성My sticky castle 코팅성Coating properties 내후성weather resistance 내식성corrosion resistance 용액
안정성solution
stability
[g][g] [g][g] [g][g] [g][g] [g][g] --
실험예 18Experimental Example 18 33 33 88 22 0.10.1 2.672.67 OKOK OKOK OKOK OKOK OKOK 실시예Example
실험예 19Experimental Example 19 33 33 88 1One 0.10.1 2.672.67 OKOK OKOK OKOK OKOK OKOK 실시예Example
실험예 20Experimental Example 20 33 33 88 0.50.5 0.10.1 2.672.67 OKOK OKOK OKOK OKOK OKOK 실시예Example
실험예 21Experimental Example 21 33 33 88 22 0.50.5 2.672.67 OKOK OKOK OKOK OKOK NGNG 비교예Comparative example
실험예 22Experimental Example 22 1212 33 33 22 00 0.250.25 NGNG OKOK OKOK OKOK OKOK 비교예Comparative example
실험예 23Experimental Example 23 1212 33 33 22 0.10.1 0.250.25 NGNG OKOK OKOK OKOK OKOK 비교예Comparative example
실험예 24Experimental Example 24 1212 33 33 1One 0.10.1 0.250.25 NGNG OKOK OKOK OKOK OKOK 비교예Comparative example
실험예 25Experimental Example 25 1212 33 33 22 0.50.5 0.250.25 NGNG OKOK OKOK OKOK NGNG 비교예Comparative example
실험예 26Experimental Example 26 1212 33 33 1One 0.50.5 0.250.25 NGNG OKOK OKOK OKOK NGNG 비교예Comparative example
상기 표 3을 참조하면, 실험예 18 내지 20와 같이, 산화제인 HClO4를 첨가하였을 때와 상기 산화제를 첨가하지 않은 실험예 22을 대비하면, 상기 실험예 22는 내스티키성을 가져 끈적임이 없는 것을 확인하였다. 또한, 실험예 23 내지 실험예 26과 같이 상기 산화제를 과도하게 첨가하여, 본 발명의 인산염과 실리카의 배합비를 벗어나는 경우, 내스티키성 또는 용액 안정성에서 불량한 것을 확인하였다.Referring to Table 3, as in Experimental Examples 18 to 20, when HClO 4 as an oxidizing agent was added and Experimental Example 22 without adding the oxidizing agent, Experimental Example 22 had sticky resistance and was not sticky. confirmed. In addition, as in Experimental Examples 23 to 26, when the oxidizing agent was added excessively and the mixing ratio of phosphate and silica of the present invention was exceeded, it was confirmed that stickiness resistance or solution stability was poor.
실험예 27 내지 36Experimental Examples 27 to 36
실험예 27 내지 36은 방향성 전기강판용 절연 피막 조성물의 조성을 하기 표 4에 기재된 함량 범위로 제어하는 것과 질산염으로 질산알루미늄 외에 질산 마그네슘을 함께 첨가하는 점, 산화제로 HClO4를 사용하는 점 이외에 실험예 1 내지 9와 동일한 방법으로 상기 절연 피막 조성물을 제조하고, 이를 평가하였다.In Experiments 27 to 36, in addition to controlling the composition of the insulating coating composition for grain-oriented electrical steel within the content range shown in Table 4, adding magnesium nitrate in addition to aluminum nitrate as a nitrate, and using HClO 4 as an oxidizing agent, Experiment Example 1 The insulating coating composition was prepared in the same manner as in 9 to 9, and was evaluated.
구분division 조성Furtherance 특성characteristic 비고note
인산염phosphate 물water Silica Silica 질산
마그
네슘nitric acid
marg
nesium 		질산
알루
미늄nitric acid
Aloo
Minium 		HClO4 HClO 4 실리카/
인산염Silica/
phosphate 		내스티키성My sticky castle 내후성weather resistance 내식성corrosion resistance 용액
안정성solution
stability
[g][g] [g][g] [g][g] [g][g] [g][g] [g][g] --
실험예 27Experimental Example 27 5.65.6 5.45.4 7.47.4 22 22 0.010.01 1.321.32 NGNG OKOK OKOK OKOK 비교예Comparative example
실험예 28Experimental Example 28 5.65.6 5.45.4 7.47.4 22 22 0.50.5 1.321.32 OKOK OKOK OKOK NGNG 비교예Comparative example
실험예 29Experimental Example 29 5.65.6 5.45.4 7.47.4 22 22 0.20.2 1.321.32 OKOK OKOK OKOK OKOK 실시예Example
실험예 30Experimental Example 30 5.65.6 5.45.4 7.47.4 0.50.5 0.50.5 00 1.321.32 NGNG OKOK OKOK OKOK 비교예Comparative example
실험예 31Experimental Example 31 5.65.6 5.45.4 7.47.4 22 22 0.10.1 1.321.32 OKOK OKOK OKOK OKOK 실시예Example
실험예 32Experimental Example 32 5.65.6 5.45.4 7.47.4 1One 1One 0.10.1 1.321.32 OKOK OKOK OKOK OKOK 실시예Example
실험예 33Experimental Example 33 33 33 88 22 22 00 2.672.67 NGNG OKOK OKOK OKOK 비교예Comparative example
실험예 34Experimental Example 34 33 33 88 22 22 0.10.1 2.672.67 OKOK OKOK OKOK OKOK 실시예Example
실험예 35Experimental Example 35 33 33 88 1One 1One 0.10.1 2.672.67 OKOK OKOK OKOK OKOK 실시예Example
실험예 36Experimental Example 36 33 33 88 22 22 0.50.5 2.672.67 OKOK OKOK OKOK NGNG 비교예Comparative example
상기 표 4를 참조하면, 실험예 29, 실험예 31, 실험예 32, 실험예 34, 및 실험예 35의 경우, 질산염으로 질산 마그네슘 및 질산 알루미늄을 동시에 첨가하고, 산화제로 HClO4를 포함하는 경우, 상기 산화제를 포함하지 않는 실험예 33와 비교하여 내스티키성이 양호한 것을 확인하였다. 또한, 실험예 27 및 실험예 28과 같이, 산화제의 함량이 과도하게 많거나 적은 경우, 내스티키성 또는 용액 안정성이 불량한 것을 확인하였다. 또한, 실험예 30은 질산 마그네슘 및 질산 알루미늄의 합량이 1 g으로 질산염의 함량이 과도하게 적은 경우, 내스티키성이 불량인 것을 확인하였다. 또한, 실험예 36과 같이, 산화제의 함량이 과도하게 많은 경우, 내스티키성 및 용액 안정성이 불량인 것을 확인하였다.Referring to Table 4, in the case of Experimental Example 29, Experimental Example 31, Experimental Example 32, Experimental Example 34, and Experimental Example 35, magnesium nitrate and aluminum nitrate were simultaneously added as nitrate and HClO 4 was included as the oxidizing agent. , it was confirmed that the sticky resistance was good compared to Experimental Example 33, which did not contain the oxidizing agent. In addition, as in Experimental Examples 27 and 28, it was confirmed that when the content of the oxidizing agent was excessively high or low, stickiness resistance or solution stability was poor. Additionally, Experimental Example 30 confirmed that when the total amount of magnesium nitrate and aluminum nitrate was 1 g and the nitrate content was excessively low, the sticky resistance was poor. In addition, as in Experimental Example 36, it was confirmed that when the content of the oxidizing agent was excessively high, stickiness resistance and solution stability were poor.
실험예 37 내지 47 - 경화 온도 테스트Experimental Examples 37 to 47 - Curing temperature test
하기 표 5는 동일한 조성의 방향성 전기강판용 절연 피막 조성물에 대해 경화 온도 및 경화 시간을 하기 표 4와 같이 조절하였을 때의 내스티키성, 내후성, 및 내식성을 평가한 것이다.Table 5 below evaluates the stickiness resistance, weather resistance, and corrosion resistance of insulating coating compositions for grain-oriented electrical steel sheets of the same composition when the curing temperature and curing time are adjusted as shown in Table 4 below.
구분division 조성Furtherance 경화 조건curing conditions 특성characteristic 비고note
인산염phosphate 물water SilicaSilica 질산
알루
미늄nitric acid
Aloo
Minium 		HClO4 HClO 4 경화
온도Hardening
temperature 		경화
시간Hardening
hour 		내스티키성My sticky castle 내후성weather resistance 내식성corrosion resistance
[g][g] [g][g] [g][g] [g][g] [g][g] [℃][℃] [초][candle]
실험예 37Experimental Example 37 5.65.6 5.45.4 7.47.4 2.02.0 0.10.1 750750 4545 NGNG NGNG NGNG 비교예Comparative example
실험예 38Experimental Example 38 5.65.6 5.45.4 7.47.4 2.02.0 0.10.1 800800 4545 OKOK OKOK OKOK 실시예Example
실험예 39Experimental Example 39 5.65.6 5.45.4 7.47.4 2.02.0 0.10.1 850850 4545 OKOK OKOK OKOK 실시예Example
실험예 40Experimental Example 40 5.65.6 5.45.4 7.47.4 2.02.0 0.10.1 900900 4545 OKOK OKOK OKOK 실시예Example
실험예 41Experimental Example 41 5.65.6 5.45.4 7.47.4 2.02.0 0.10.1 950950 4545 OKOK NGNG NGNG 비교예Comparative example
실험예 42Experimental Example 42 5.65.6 5.45.4 7.47.4 2.02.0 0.10.1 800800 2020 OKOK OKOK OKOK 실시예Example
실험예 43Experimental Example 43 5.65.6 5.45.4 7.47.4 2.02.0 0.10.1 900900 2020 OKOK OKOK OKOK 실시예Example
실험예 44Experimental Example 44 5.65.6 5.45.4 7.47.4 2.02.0 0.10.1 800800 180180 OKOK OKOK OKOK 실시예Example
실험예 45Experimental Example 45 5.65.6 5.45.4 7.47.4 2.02.0 0.10.1 900900 180180 OKOK OKOK OKOK 실시예Example
실험예 46Experimental Example 46 5.65.6 5.45.4 7.47.4 2.02.0 0.10.1 800800 600600 OKOK NGNG NGNG 비교예Comparative example
실험예 47Experimental Example 47 5.65.6 5.45.4 7.47.4 2.02.0 0.10.1 900900 600600 OKOK NGNG NGNG 비교예Comparative example
상기 표 5를 살펴보면, 경화 조건에 있어서, 경화 온도가 본 발명의 범위인 실험예 38 내지 40는 경화 온도가 본 발명의 범위를 벗어나는 실험예 37 및 실험예 41과 대비하여 내스티키성, 내후성, 및 내식성이 양호한 것을 확인하였다.상기 실험예 42 내지 47을 살펴보면, 경화 조건에 있어서, 경화 시간이 본 발명의 범위인 실험예 42 내지 45는 내스티키성, 내후성, 및 내식성이 양호하나, 상기 경화 시간이 본 발명의 범위를 벗어나는 실험예 46 및 47은 내스티키성, 내후성, 및 내식성 중 적어도 하나가 불량한 것을 확인하였다.Looking at Table 5, in terms of curing conditions, Experimental Examples 38 to 40, where the curing temperature is within the range of the present invention, have stickiness resistance, weather resistance, and And it was confirmed that the corrosion resistance was good. Looking at Experimental Examples 42 to 47, in terms of curing conditions, Experimental Examples 42 to 45, where the curing time was within the range of the present invention, had good stickiness resistance, weather resistance, and corrosion resistance, but the curing In Experimental Examples 46 and 47, where the time was outside the scope of the present invention, it was confirmed that at least one of stickiness resistance, weather resistance, and corrosion resistance was poor.
본 발명은 상기 구현예 및/또는 실시예들에 한정되는 것이 아니라 서로 다른 다양한 형태로 제조될 수 있으며, 본 발명이 속하는 기술분야에서 통상의 지식을 가진 자는 본 발명의 기술적 사상이나 필수적인 특징을 변경하지 않고서 다른 구체적인 형태로 실시될 수 있다는 것을 이해할 수 있을 것이다. 그러므로 이상에서 기술한 구현예 및/또는 실시예들은 모든 면에서 예시적인 것이며 한정적이 아닌 것으로 이해해야만 한다.The present invention is not limited to the above embodiments and/or examples, but can be manufactured in various different forms, and those skilled in the art may change the technical idea or essential features of the present invention. You will be able to understand that it can be implemented in another specific form without doing so. Therefore, the implementation examples and/or embodiments described above should be understood in all respects as illustrative and not restrictive.

Claims (14)

  1. 인산염;phosphate;
    실리카;silica;
    질산염; 및nitrate; and
    산화제를 포함하고,Contains an oxidizing agent,
    상기 실리카는 상기 인산염 100 중량부를 기준으로, 고형분 50 내지 400 중량부를 포함하고,The silica contains 50 to 400 parts by weight of solid content, based on 100 parts by weight of the phosphate,
    상기 인산염 고형분에 대한 상기 실리카 고형분의 배합비는 0.3 내지 3.9 이며,The mixing ratio of the silica solid content to the phosphate solid content is 0.3 to 3.9,
    상기 산화제는 상기 인산염 100 중량부를 기준으로, 고형분 0.5 내지 10.0 중량부를 포함하는 방향성 전기강판용 절연 피막 조성물.The oxidizing agent is an insulating coating composition for a grain-oriented electrical steel sheet including a solid content of 0.5 to 10.0 parts by weight based on 100 parts by weight of the phosphate.
  2. 제1 항에 있어서,According to claim 1,
    상기 질산염은 질산알루미늄(Al(NO3)3), 질산코발트(Co(NO3)2), 질산칼슘(Ca(NO3)2), 질산스트론튬(Sr(NO3)2), 질산아연(Zn(NO3)2), 질산망간(Mn(NO3)2), 질산마그네슘(Mg(NO3)2), 및 질산은(AgNO3) 중 적어도 어느 하나를 포함하는 방향성 전기강판용 절연 피막 조성물.The nitrate includes aluminum nitrate (Al(NO 3 ) 3 ), cobalt nitrate (Co(NO 3 ) 2 ), calcium nitrate (Ca(NO 3 ) 2 ), strontium nitrate (Sr(NO 3 ) 2 ), and zinc nitrate ( An insulating coating composition for a grain-oriented electrical steel sheet containing at least one of Zn(NO 3 ) 2 ), manganese nitrate (Mn(NO 3 ) 2 ), magnesium nitrate (Mg(NO 3 ) 2 ), and silver nitrate (AgNO 3 ).
  3. 제2 항에 있어서,According to clause 2,
    상기 질산염은 질산알루미늄(Al(NO3)3), 질산코발트(Co(NO3)2), 질산칼슘(Ca(NO3)2), 질산스트론튬(Sr(NO3)2), 질산아연(Zn(NO3)2), 질산망간(Mn(NO3)2), 질산마그네슘(Mg(NO3)2), 및 질산은(AgNO3) 중 적어도 2 이상을 포함하는 방향성 전기강판용 절연 피막 조성물.The nitrate includes aluminum nitrate (Al(NO 3 ) 3 ), cobalt nitrate (Co(NO 3 ) 2 ), calcium nitrate (Ca(NO 3 ) 2 ), strontium nitrate (Sr(NO 3 ) 2 ), and zinc nitrate ( An insulating coating composition for a grain-oriented electrical steel sheet containing at least two of Zn(NO 3 ) 2 ), manganese nitrate (Mn(NO 3 ) 2 ), magnesium nitrate (Mg(NO 3 ) 2 ), and silver nitrate (AgNO 3 ).
  4. 제1 항에 있어서,According to claim 1,
    상기 질산염은 상기 인산염 100 중량부를 기준으로, 고형분 5 내지 100 중량부를 포함하는 방향성 전기강판용 절연 피막 조성물.The nitrate is an insulating coating composition for a grain-oriented electrical steel sheet containing 5 to 100 parts by weight of solid content, based on 100 parts by weight of the phosphate.
  5. 제1 항에 있어서,According to claim 1,
    상기 산화제는 HClO4, NaClO, NaClO4, KMnO4, NaIO4, OsO4, H2O2, Ca(ClO)2 중 적어도 어느 하나를 포함하는 방향성 전기강판용 절연 피막 조성물.The oxidizing agent is HClO 4 , NaClO, NaClO 4 , KMnO 4 , NaIO 4 , OsO 4 , H 2 O 2 , and Ca(ClO) 2 Insulating coating composition for grain-oriented electrical steel sheets.
  6. 전기강판 기재 및Electrical steel base material and
    상기 전기강판 기재의 표면 상에 위치하는 절연피막을 포함하고,It includes an insulating film located on the surface of the electrical steel sheet base,
    상기 절연피막은 인산염, 실리카, 질산염, 및 산화제를 포함하고,The insulating film contains phosphate, silica, nitrate, and oxidizing agent,
    상기 실리카는 인산염 100 중량부를 기준으로, 고형분 50 내지 400 중량부를 포함하고,The silica contains 50 to 400 parts by weight of solid content based on 100 parts by weight of phosphate,
    상기 인산염 고형분에 대한 상기 실리카 고형분의 배합비는 0.3 내지 3.9 이고,The mixing ratio of the silica solid content to the phosphate solid content is 0.3 to 3.9,
    상기 산화제는 상기 인산염 100 중량부를 기준으로, 고형분 0.5 내지 10.0 중량부를 포함하는 방향성 전기강판.The oxidizing agent is a grain-oriented electrical steel sheet containing 0.5 to 10.0 parts by weight of solid content, based on 100 parts by weight of the phosphate.
  7. 전기강판 기재를 준비하는 단계;Preparing an electrical steel base material;
    상기 전기강판 기재의 표면에 절연 코팅 조성물을 도포하는 단계; 및Applying an insulating coating composition to the surface of the electrical steel substrate; and
    상기 절연 코팅 조성물을 경화시키는 단계를 포함하며,comprising curing the insulating coating composition,
    상기 절연 코팅 조성물은 인산염, 실리카, 질산염, 및 산화제를 포함하고,The insulating coating composition includes phosphate, silica, nitrate, and oxidizing agent,
    상기 실리카는 인산염 100 중량부를 기준으로, 고형분 50 내지 400 중량부를 포함하고 상기 인산염 고형분에 대한 상기 실리카 고형분의 배합비는 0.3 내지 3.9 이고 상기 산화제는 상기 인산염 100 중량부를 기준으로, 고형분 0.5 내지 10.0 중량부를 포함하며,The silica includes a solid content of 50 to 400 parts by weight based on 100 parts by weight of phosphate, the mixing ratio of the silica solid content to the phosphate solid content is 0.3 to 3.9, and the oxidizing agent has a solid content of 0.5 to 10.0 parts by weight based on 100 parts by weight of the phosphate. Includes,
    상기 절연 코팅 조성물을 경화시키는 단계는 800 내지 900 ℃ 범위에서 30 초 내지 180초 범위로 수행되는 방향성 전기강판의 제조 방법.A method of manufacturing a grain-oriented electrical steel sheet, wherein the step of curing the insulating coating composition is performed at a temperature of 800 to 900° C. for 30 to 180 seconds.
  8. 제7 항에 있어서,According to clause 7,
    상기 전기강판 기재의 표면에 절연 코팅 조성물을 도포하는 단계는 인산염 및 실리카를 투입하여 혼용하는 단계; 혼용된 용액에 질산염을 투입하는 단계; 및 이후, 산화제를 첨가하는 단계를 포함하는 방향성 전기강판의 제조 방법.The step of applying an insulating coating composition to the surface of the electrical steel substrate includes adding and mixing phosphate and silica; Adding nitrate to the mixed solution; And then, a method of manufacturing a grain-oriented electrical steel sheet including the step of adding an oxidizing agent.
  9. 제7 항에 있어서,According to clause 7,
    전기강판 기재를 준비하는 단계는The steps to prepare the electrical steel base material are:
    강 슬라브를 준비하는 단계;Preparing river slabs;
    상기 강 슬라브를 가열하는 단계;heating the steel slab;
    가열된 상기 강 슬라브를 열간 압연하여 열연 강판을 제조하는 단계;Manufacturing a hot rolled steel sheet by hot rolling the heated steel slab;
    상기 열연 강판을 냉간 압연시켜 냉연 강판을 제조하는 단계;Manufacturing a cold-rolled steel sheet by cold-rolling the hot-rolled steel sheet;
    냉연판을 1차 재결정 소둔하는 단계;Primary recrystallization annealing of the cold rolled sheet;
    1차 재결정 소둔된 강판 상에 소둔 분리제를 도포하는 단계; 및Applying an annealing separator on a steel sheet subjected to primary recrystallization annealing; and
    2차 재결정 소둔을 수행하는 단계를 포함하는 방향성 전기강판의 제조 방법.A method of manufacturing a grain-oriented electrical steel sheet comprising performing secondary recrystallization annealing.
  10. 제9 항에 있어서,According to clause 9,
    상기 1차 재결정 소둔된 강판 상에 소둔 분리제를 도포하는 단계는 상기 소둔 분리제를 1 내지 5 g/m2 범위로 도포하는 단계를 포함하는 방향성 전기강판의 The step of applying an annealing separator on the primary recrystallization annealed steel sheet includes applying the annealing separator in a range of 1 to 5 g/m 2 of the grain-oriented electrical steel sheet.
    제조 방법.Manufacturing method.
  11. 제9 항에 있어서,According to clause 9,
    상기 2차 재결정 소둔하는 단계는 균열 단계 및 승온 단계를 포함하며,The secondary recrystallization annealing step includes a cracking step and a temperature raising step,
    상기 균열 단계는 650 내지 750 ℃ 범위에서 수행되고, 상기 승온 단계는 1,100 내지 1,250 ℃ 범위에서 수행되는 방향성 전기강판의 제조 방법.The cracking step is performed in the range of 650 to 750 ℃, and the temperature raising step is performed in the range of 1,100 to 1,250 ℃.
  12. 제11 항에 있어서,According to claim 11,
    상기 승온 단계는 10 내지 20 ℃/hr 범위의 승온 속도로 수행되는 방향성 전기강판의 제조 방법.The temperature increasing step is a method of manufacturing a grain-oriented electrical steel sheet, wherein the temperature increasing step is performed at a temperature increasing rate in the range of 10 to 20 ℃/hr.
  13. 제11 항에 있어서,According to claim 11,
    상기 균열 단계는 수소 가스, 질소 가스, 비활성 기체 가스 중 2 이상의 가스 분위기에서 수행되는 방향성 전기강판의 제조 방법.The cracking step is a method of manufacturing a grain-oriented electrical steel sheet wherein the cracking step is performed in a gas atmosphere of two or more of hydrogen gas, nitrogen gas, and inert gas gas.
  14. 제11항에 있어서,According to clause 11,
    상기 승온 단계는 수소 분위기에서 수행되는 방향성 전기강판의 제조 방법.The temperature raising step is a method of manufacturing a grain-oriented electrical steel sheet performed in a hydrogen atmosphere.
PCT/KR2023/020527 2022-12-19 2023-12-13 Insulation coating composition, grain-oriented electrical steel sheet comprising same, and method of manufacturing grain-oriented electrical steel sheet WO2024136278A1 (en)

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JP2012158800A (en) * 2011-01-31 2012-08-23 Jfe Steel Corp Grain oriented electromagnetic steel sheet with chromeless stress coating
KR20140085747A (en) * 2012-12-27 2014-07-08 주식회사 포스코 Tension coating composite for oriented electrical steel steet, forming method of tension coating using the same and oriented electrical steel steet using the method
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US20180312936A1 (en) * 2015-10-20 2018-11-01 Posco Composition for forming insulation film of oriented electrical steel sheet, method for forming insulation film by using same, and oriented electrical steel sheet having insulation film formed therein

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2012158800A (en) * 2011-01-31 2012-08-23 Jfe Steel Corp Grain oriented electromagnetic steel sheet with chromeless stress coating
KR20140085747A (en) * 2012-12-27 2014-07-08 주식회사 포스코 Tension coating composite for oriented electrical steel steet, forming method of tension coating using the same and oriented electrical steel steet using the method
KR20180011349A (en) * 2014-04-24 2018-01-31 제이에프이 스틸 가부시키가이샤 Treatment solution for chromium-free insulating coating for grain-oriented electrical steel sheet and grain-oriented electrical steel sheet coated with chromium-free insulating coating
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