WO2023075282A1 - Ferritic stainless steel having improved magnetic properties and manufacturing method therefor - Google Patents
Ferritic stainless steel having improved magnetic properties and manufacturing method therefor Download PDFInfo
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- WO2023075282A1 WO2023075282A1 PCT/KR2022/015945 KR2022015945W WO2023075282A1 WO 2023075282 A1 WO2023075282 A1 WO 2023075282A1 KR 2022015945 W KR2022015945 W KR 2022015945W WO 2023075282 A1 WO2023075282 A1 WO 2023075282A1
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- 229910001220 stainless steel Inorganic materials 0.000 title claims abstract description 41
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 25
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims abstract description 25
- 239000012535 impurity Substances 0.000 claims abstract description 15
- 230000035699 permeability Effects 0.000 claims description 32
- 239000000463 material Substances 0.000 claims description 19
- 238000000034 method Methods 0.000 claims description 13
- 238000000137 annealing Methods 0.000 claims description 10
- 229910052799 carbon Inorganic materials 0.000 claims description 8
- 229910052804 chromium Inorganic materials 0.000 claims description 8
- 229910052742 iron Inorganic materials 0.000 claims description 8
- 229910052750 molybdenum Inorganic materials 0.000 claims description 8
- 229910052757 nitrogen Inorganic materials 0.000 claims description 8
- 238000003303 reheating Methods 0.000 claims description 8
- 229910052710 silicon Inorganic materials 0.000 claims description 8
- 229910052719 titanium Inorganic materials 0.000 claims description 8
- 238000005097 cold rolling Methods 0.000 claims description 7
- 229910052748 manganese Inorganic materials 0.000 claims description 7
- 238000005098 hot rolling Methods 0.000 claims description 6
- 230000009467 reduction Effects 0.000 claims description 5
- 229910052718 tin Inorganic materials 0.000 claims description 4
- 229910045601 alloy Inorganic materials 0.000 abstract description 7
- 239000000956 alloy Substances 0.000 abstract description 7
- 230000004043 responsiveness Effects 0.000 abstract description 3
- 239000011651 chromium Substances 0.000 description 35
- 230000000052 comparative effect Effects 0.000 description 17
- 239000010936 titanium Substances 0.000 description 16
- 239000011572 manganese Substances 0.000 description 12
- 230000001747 exhibiting effect Effects 0.000 description 8
- 239000010955 niobium Substances 0.000 description 8
- 238000001556 precipitation Methods 0.000 description 7
- 230000009257 reactivity Effects 0.000 description 7
- 239000002244 precipitate Substances 0.000 description 6
- 230000007797 corrosion Effects 0.000 description 5
- 238000005260 corrosion Methods 0.000 description 5
- 239000000203 mixture Substances 0.000 description 5
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 4
- 239000013078 crystal Substances 0.000 description 4
- 230000007423 decrease Effects 0.000 description 4
- 230000014509 gene expression Effects 0.000 description 4
- 229910000831 Steel Inorganic materials 0.000 description 3
- 239000010959 steel Substances 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 230000006866 deterioration Effects 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 230000005389 magnetism Effects 0.000 description 2
- 230000007257 malfunction Effects 0.000 description 2
- 239000000047 product Substances 0.000 description 2
- 239000000523 sample Substances 0.000 description 2
- 239000011780 sodium chloride Substances 0.000 description 2
- 238000005482 strain hardening Methods 0.000 description 2
- 230000007704 transition Effects 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 1
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 description 1
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 description 1
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 description 1
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 1
- 238000005266 casting Methods 0.000 description 1
- 230000000593 degrading effect Effects 0.000 description 1
- 230000005672 electromagnetic field Effects 0.000 description 1
- 239000000696 magnetic material Substances 0.000 description 1
- 230000005415 magnetization Effects 0.000 description 1
- 150000001247 metal acetylides Chemical class 0.000 description 1
- 239000011733 molybdenum Substances 0.000 description 1
- 229910052758 niobium Inorganic materials 0.000 description 1
- GUCVJGMIXFAOAE-UHFFFAOYSA-N niobium atom Chemical compound [Nb] GUCVJGMIXFAOAE-UHFFFAOYSA-N 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 238000002161 passivation Methods 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 230000003313 weakening effect Effects 0.000 description 1
- 229910000859 α-Fe Inorganic materials 0.000 description 1
Classifications
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D6/00—Heat treatment of ferrous alloys
- C21D6/002—Heat treatment of ferrous alloys containing Cr
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0221—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the working steps
- C21D8/0226—Hot rolling
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0221—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the working steps
- C21D8/0236—Cold rolling
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0247—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment
- C21D8/0273—Final recrystallisation annealing
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/46—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for sheet metals
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/001—Ferrous alloys, e.g. steel alloys containing N
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/22—Ferrous alloys, e.g. steel alloys containing chromium with molybdenum or tungsten
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/26—Ferrous alloys, e.g. steel alloys containing chromium with niobium or tantalum
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/28—Ferrous alloys, e.g. steel alloys containing chromium with titanium or zirconium
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/34—Ferrous alloys, e.g. steel alloys containing chromium with more than 1.5% by weight of silicon
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D2211/00—Microstructure comprising significant phases
- C21D2211/005—Ferrite
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C2202/00—Physical properties
- C22C2202/02—Magnetic
Definitions
- the present invention relates to a ferritic stainless steel having improved magnetic properties by controlling alloy components and a manufacturing process in order to increase responsiveness to an externally applied magnetic field and a manufacturing method thereof.
- a material having high magnetic permeability has excellent shielding ability, and in particular, a demand for a material exhibiting high magnetic permeability against a low externally applied magnetic field is increasing.
- An object of the present invention to solve the above problems is to provide a ferritic stainless steel with improved magnetic properties and a method for manufacturing the same, which has increased reactivity to electromagnetic wave shielding by exhibiting a large magnetic permeability to a low externally applied magnetic field. .
- Ferritic stainless steel with improved magnetic properties according to an embodiment of the present invention, in weight%, C: greater than 0% and 0.02% or less, N: greater than 0% and 0.02% or less, Si: 0.5% or more and 2.0% or less, Mn: 0.1% or more and 0.3% or less, Cr: 16.0% or more and 20.1% or less, Mo: 1.0% or more and 2.0% or less, Ti: 0.1% or more and 0.4% or less, the remainder including Fe (iron) and other unavoidable impurities, including the following The value of Equation (1) may be 130 or less.
- Equation (1) 30 + 2500 * ([C] + [N]) - 15 * [Si] + 2.5 * [Cr] + 22 * [Mo]
- [C], [N], [Si], [Cr], and [Mo] mean the content (wt%) of each element.
- ferritic stainless steel having improved magnetic properties may have a value of 50 or less in Equation (2) below.
- Equation (2) 18 + 800 * ([C] + [N]) - 6 * [Si] + [Cr] + 6 * [Mo]
- ferritic stainless steel with improved magnetic properties may further include Nb: more than 0% and less than 0.1% and Sn: more than 0% and less than 0.1%, in weight%.
- ferritic stainless steel having improved magnetic properties may have a maximum magnetic permeability of 1,000 or more in a 50Hz frequency band.
- ferritic stainless steel having improved magnetic properties according to an embodiment of the present invention may have an externally applied magnetic field of 130 A/m or less to exhibit maximum magnetic permeability.
- ferritic stainless steel having improved magnetic properties may have a coercive force of less than 50 A/m under conditions of maximum magnetic permeability in a 50 Hz frequency band.
- ferritic stainless steel having improved magnetic properties may have a pitting potential value of 300 mV or more.
- ferritic stainless steel having improved magnetic properties may have a hardness of Hv 140 or more.
- Equation (1) 30 + 2500 * ([C] + [N]) - 15 * [Si] + 2.5 * [Cr] + 22 * [Mo]
- [C], [N], [Si], [Cr], and [Mo] mean the content (wt%) of each element.
- Equation (2) 18 + 800 * ([C] + [N]) - 6 * [Si] + [Cr] + 6 * [Mo]
- the cold rolling may be performed at a reduction ratio of 70% or more.
- a ferritic stainless steel with improved magnetic properties which has increased reactivity to electromagnetic wave shielding by deriving a component system exhibiting high permeability and exhibiting a large permeability to a low externally applied magnetic field, and manufacturing thereof method can be provided.
- Ferritic stainless steel with improved magnetic properties according to an embodiment of the present invention, in weight%, C: greater than 0% and 0.02% or less, N: greater than 0% and 0.02% or less, Si: 0.5% or more and 2.0% or less, Mn: 0.1% or more and 0.3% or less, Cr: 16.0% or more and 20.1% or less, Mo: 1.0% or more and 2.0% or less, Ti: 0.1% or more and 0.4% or less, the remainder including Fe (iron) and other unavoidable impurities, including the following The value of Equation (1) may be 130 or less.
- Equation (1) 30 + 2500 * ([C] + [N]) - 15 * [Si] + 2.5 * [Cr] + 22 * [Mo]
- [C], [N], [Si], [Cr], and [Mo] mean the content (wt%) of each element.
- Ferritic stainless steel with improved magnetic properties according to an embodiment of the present invention, in weight%, C: greater than 0% and 0.02% or less, N: greater than 0% and 0.02% or less, Si: 0.5% or more and 2.0% or less, Mn: 0.1% or more and 0.3% or less, Cr: 16.0% or more and 20.1% or less, Mo: 1.0% or more and 2.0% or less, Ti: 0.1% or more and 0.4% or less, the balance may include Fe (iron) and other unavoidable impurities .
- the content of C (carbon) may be greater than 0% and 0.02% or less.
- C is an impurity element inevitably contained in steel, it is desirable to lower its content as much as possible.
- the content of C is excessive, since magnetic properties deteriorate due to formation of carbides, magnetic permeability may deteriorate.
- the elongation rate decreases due to the increase in impurities, the strain hardening index n value decreases, and the ductile to brittle transition temperature (DBTT) increases, resulting in a decrease in impact properties.
- the upper limit of the C content may be limited to 0.02%.
- the upper limit of the C content may preferably be limited to 0.01% by weight.
- the content of N may be more than 0% and 0.02% or less.
- the upper limit of the N content may be limited to 0.02%.
- the upper limit of the N content may preferably be limited to 0.015% by weight.
- the content of Si may be 0.5% or more and 2.0% or less.
- Si is an element effective in realizing an increase in magnetic permeability with respect to a low externally applied magnetic field. Considering this, Si may be added in an amount of 0.5% or more. However, when the content of Si is excessive, the elongation is lowered, the strain hardening index n value is lowered, and the Si-based inclusions are increased, resulting in lower workability. Considering this, the upper limit of the Si content may be limited to 2.0%. Considering workability, the upper limit of the Si content may preferably be limited to 1.0% by weight.
- the content of Mn (manganese) may be 0.1% or more and 0.3% or less.
- Mn When the content of Mn is low, fine MnS precipitates are formed to cause crystal grain refinement, thereby weakening the magnetism. Therefore, Mn may be added in an amount of 0.1% or more so that MnS precipitates can be coarsely formed. However, when the Mn content is excessive, magnetic properties may be deteriorated due to an increase in the MnS precipitate fraction. Considering this, the upper limit of the Mn content may be limited to 0.3%.
- the content of Cr (chromium) may be 16.0% or more and 20.1% or less.
- Cr is an element that improves corrosion resistance by forming a passivation film in an oxidizing environment. In consideration of this, 16.0% or more of Cr may be added. However, when the Cr content is excessive, it promotes the formation of delta ( ⁇ ) ferrite in the slab, resulting in lower elongation and impact toughness, and lower permeability. Considering this, the upper limit of the Cr content may be limited to 20.1%.
- the content of Mo (molybdenum) may be greater than 1.0% and less than or equal to 2.0%.
- Mo is an element effective in increasing the corrosion resistance of stainless steel. In consideration of this, 1.0% or more may be added. However, when the content of Mo is excessive, it is segregated at the grain boundary and plays a role of suppressing grain growth, thereby causing crystal grain refinement, so that magnetism may be inferior. Considering this, the upper limit of the Mo content may be limited to 2.0%.
- the content of Ti may be 0.1% or more and 0.4% or less.
- Ti is an effective element for improving strength by causing precipitation. Considering this, Ti may be added in an amount of 0.1% or more. However, when the content of Ti is excessive, the Ti-based precipitate is excessively increased and the crystal grain size does not become sufficiently large, resulting in a decrease in magnetic permeability. Considering this, the upper limit of the Ti content may be limited to 0.4%.
- the remaining component of the present invention is iron (Fe).
- Fe iron
- ferritic stainless steel with improved magnetic properties may further include Nb: more than 0% and less than 0.1% and Sn: more than 0% and less than 0.1%, in weight%.
- the content of Nb (niobium) may be greater than 0% and less than or equal to 0.1%.
- Nb is an element that forms a fine precipitated phase like Ti.
- Ti forms a relatively high-temperature phase
- fine precipitation can be prevented by heat treatment, but since Nb forms a stable phase at a relatively low temperature, it is re-dissolved during hot rolling and may cause fine precipitation during annealing. Therefore, when the content of Nb is excessive, magnetic deterioration due to fine precipitation may occur, so it is preferable to manage it as an impurity.
- the upper limit of the Nb content may be limited to 0.1%.
- the content of Sn (tin) may be greater than 0% and 0.1% or less.
- Sn like Ti
- Ti forms a relatively high temperature phase
- fine precipitation can be prevented by heat treatment, but Sn forms a stable phase at a relatively low temperature, so it is re-dissolved during hot rolling and may cause fine precipitation during annealing. Therefore, when the content of Sn is excessive, magnetic deterioration due to fine precipitation may occur, so it is preferable to manage it as an impurity. Considering this, the upper limit of the Sn content may be limited to 0.1%.
- Equation (1) below may be 130 or less.
- Equation (1) 30 + 2500 * ([C] + [N]) - 15 * [Si] + 2.5 * [Cr] + 22 * [Mo]
- [C], [N], [Si], [Cr], and [Mo] mean the content (wt%) of each element.
- An object of the present invention is to provide a ferritic stainless steel with improved magnetic properties and a method for manufacturing the same, which has increased reactivity to electromagnetic shielding by exhibiting a large magnetic permeability to a low externally applied magnetic field.
- the value of Equation (1) exceeds 130, since it shows a large permeability value with respect to a relatively high externally applied magnetic field, the reactivity to electromagnetic wave shielding is poor. Therefore, the value of Equation (1) may be 130 or less.
- the ferritic stainless steel with improved magnetic properties may have a maximum magnetic permeability of 1,000 or more in a 50Hz frequency band.
- the externally applied magnetic field for showing the maximum magnetic permeability may be 130 A/m or less.
- Equation (2) below may be 50 or less.
- Equation (2) 18 + 800 * ([C] + [N]) - 6 * [Si] + [Cr] + 6 * [Mo]
- the coercive force refers to the magnitude of an external magnetic field in a reverse direction required to return a magnetized magnetic material to a non-magnetized state.
- the value of Equation (2) may be 50 or less.
- the ferritic stainless steel with improved magnetic properties may have a coercive force of less than 50 A / m under the condition of showing the maximum magnetic permeability in the 50 Hz frequency band. .
- ferritic stainless steel with improved magnetic properties may have a pitting potential value of 300 mV or more by improving corrosion resistance by controlling the alloy composition and manufacturing process.
- ferritic stainless steel with improved magnetic properties may have a hardness of Hv 140 or more by improving strength by controlling the alloy composition and manufacturing process.
- Equation (1) 30 + 2500 * ([C] + [N]) - 15 * [Si] + 2.5 * [Cr] + 22 * [Mo]
- [C], [N], [Si], [Cr], and [Mo] mean the content (wt%) of each element.
- Equation (2) 18 + 800 * ([C] + [N]) - 6 * [Si] + [Cr] + 6 * [Mo]
- a series of hot rolling, cold rolling, and final annealing may be performed.
- the slab may be hot rolled at a reheating temperature of 1050 to 1150 ° C.
- the reheating temperature of the slab may be 1050 ° C or higher. However, if the reheating temperature is too high, the grain diameter of the slab may be excessively coarsened, resulting in inferior strength. Considering this, the upper limit of the reheating temperature of the slab may be limited to 1150 ° C.
- the cold rolling may be performed at a reduction ratio of 70% or more. If the reduction ratio is less than 70%, it may be difficult to achieve the desired strength.
- the cold-rolled material may be final annealed at 1050 to 1150 ° C.
- the final annealing temperature is low, it takes a long time, and manufacturing cost may increase. Considering this, the final annealing temperature may be 1050 °C or more. However, if the final annealing temperature is high, the microstructure may be excessively coarse, and mechanical properties may be deteriorated. Considering this, the final annealing temperature may be 1150 °C or less.
- equation (1) The values of equation (1) and equation (2), maximum magnetic permeability, applied magnetic field, coercive force, pit potential and hardness are shown in Table 2 below.
- the value of equation (1) is 30 + 2500 * ([C] + [N]) - This is the calculated value of 15 * [Si] + 2.5 * [Cr] + 22 * [Mo].
- [C], [N], [Si], [Cr], [Mo] means the content (wt%) of each element.
- Equation (2) is a calculated value of 18 + 800 * ([C] + [N]) - 6 * [Si] + [Cr] + 6 * [Mo].
- the magnetic properties were evaluated by measuring the magnetic field due to the magnetization of the material while gradually increasing the externally applied magnetic field in a 50 Hz frequency band.
- the maximum magnetic permeability was measured using a non-magnetic magnetic permeability meter having a model name of Ferropro FP-5 by contacting a probe to a cross section of a steel sample having a diameter of 20 mm or more and a thickness of 5 mm or more.
- the pitting potential represents a value measured by immersing in a NaCl solution and applying a potential to generate pitting potential.
- the temperature of the NaCl solution was set to 30 °C and the concentration was set to 3.5%.
- Hardness was measured using a Vickers hardness tester from Zwick Roell.
- Examples 1 to 7 all satisfied the value of Equation (1) of 130 or less and the value of Equation (2) of 50 or less. Therefore, the maximum magnetic permeability in the 50Hz frequency band was 1,000 or more, the externally applied magnetic field to indicate the maximum permeability was 130 A/m or less, and the coercive force was less than 50 A/m under the conditions of maximum permeability. . That is, it can be seen that Examples 1 to 7 exhibit high magnetic permeability to a low externally applied magnetic field, thereby increasing reactivity to electromagnetic wave shielding and improving magnetic properties. In addition, Examples 1 to 7 had a pitting potential value of 300 mV or more and a hardness of Hv 140 or more. That is, Examples 1 to 7 were excellent in corrosion resistance and strength.
- Comparative Examples 1 to 5 the value of Formula (1) did not satisfy 130 or less. Accordingly, Comparative Examples 1 to 5 did not satisfy the externally applied magnetic field of 130 A/m or less to indicate the maximum magnetic permeability. In Comparative Examples 1 to 5, the value of Formula (2) did not satisfy 50 or less. Therefore, Comparative Examples 1 to 5 did not satisfy the coercive force of less than 50 A/m. That is, since Comparative Examples 1 to 5 had a relatively high externally applied magnetic field, it could be seen that their reactivity to electromagnetic wave shielding was inferior.
- Comparative Example 4 Mo component was not added, and the pitting potential value did not satisfy 300 mV or more due to the relatively low level of Cr content. That is, Comparative Example 4 was inferior in corrosion resistance.
- a ferritic stainless steel with improved magnetic properties which has increased reactivity to electromagnetic wave shielding by deriving a component system exhibiting high permeability and exhibiting a large permeability to a low externally applied magnetic field, and manufacturing thereof As a method can be provided, industrial applicability is recognized.
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- Soft Magnetic Materials (AREA)
Abstract
Disclosed herein are ferritic stainless steel and a manufacturing method wherein the ferritic stainless steel has magnetic properties improved by controlling alloy components and a manufacturing process in order to increase responsiveness to an externally applied magnetic field. The ferritic stainless steel having improved magnetic properties according to an embodiment of the present invention may include, by % by weight, C: 0% (exclusive) to 0.02% (inclusive), N: 0% (exclusive) to 0.02% (inclusive), Si: 0.5% to 2.0% (both inclusive), Mn: 0.1% to 0.3% (both inclusive), Cr: 16.0% to 20.1% (both inclusive), Mo: 1.0% (exclusive) to 2.0% (inclusive), Ti: 0.1% to 0.4% (both inclusive), and the balance of iron (Fe) and inevitable impurities.
Description
본 발명은 외부 인가 자기장에 대한 응답성을 높이기 위해, 합금성분 및 제조공정을 제어함으로써 자기적 성질을 향상시킨 페라이트계 스테인리스강 및 그 제조방법에 관한 것이다.The present invention relates to a ferritic stainless steel having improved magnetic properties by controlling alloy components and a manufacturing process in order to increase responsiveness to an externally applied magnetic field and a manufacturing method thereof.
최근 스마트폰, 반자율주행 자동차 등의 기술분야의 발달로 다양한 전자기기를 사용하면서, 전자파의 이용이 급증하였다. 이에 따라, 전자기기간의 전자파에 의한 간섭이 증가하였다. 전자파의 간섭은 기기 오작동을 유발하거나 기기의 정밀 제어를 어렵게 한다. 전자파 간섭으로 인한 전자기기의 오작동을 방지하기 위해서는 자기장을 차폐할 수 있는 소재로 중요 소자들을 감싸야 한다.Recently, with the development of technology fields such as smart phones and semi-autonomous vehicles, the use of electromagnetic waves has increased rapidly while using various electronic devices. Accordingly, interference caused by electromagnetic waves between electromagnetic fields has increased. Interference of electromagnetic waves causes equipment malfunction or makes precise control of equipment difficult. In order to prevent malfunction of electronic devices due to electromagnetic interference, important elements must be covered with materials capable of shielding magnetic fields.
낮은 주파수 혹은 자기장 차폐의 경우 투자율(magnetic permeability)이 높은 소재가 차폐능이 우수하며, 특히, 낮은 외부 인가 자기장에 대해 높은 투자율을 나타내는 소재에 대한 요구가 증가하고 있다.In the case of shielding a low frequency or magnetic field, a material having high magnetic permeability has excellent shielding ability, and in particular, a demand for a material exhibiting high magnetic permeability against a low externally applied magnetic field is increasing.
종래에는 높은 외부 인가 자기장에 대해 높은 투자율을 나타내는 소재에 대한 연구가 진행되어 왔으나, 이는 외부 인가 자기장에 대한 응답성이 열위하다는 문제점이 있다.Conventionally, research on a material exhibiting high permeability to a high externally applied magnetic field has been conducted, but this has a problem in that responsiveness to an externally applied magnetic field is inferior.
상술한 문제를 해결하기 위한 본 발명의 목적은, 낮은 외부 인가 자기장에 대해 큰 투자율을 나타냄으로써 전자파 차폐에 대한 반응성을 증가시킨, 자기적 성질이 향상된 페라이트계 스테인리스강 및 그 제조방법을 제공하는 것이다.An object of the present invention to solve the above problems is to provide a ferritic stainless steel with improved magnetic properties and a method for manufacturing the same, which has increased reactivity to electromagnetic wave shielding by exhibiting a large magnetic permeability to a low externally applied magnetic field. .
본 발명의 일 실시예에 따른 자기적 성질이 향상된 페라이트계 스테인리스강은, 중량%로, C: 0% 초과 0.02% 이하, N: 0% 초과 0.02% 이하, Si: 0.5% 이상 2.0% 이하, Mn: 0.1% 이상 0.3% 이하, Cr: 16.0% 이상 20.1% 이하, Mo: 1.0% 초과 2.0% 이하, Ti: 0.1% 이상 0.4% 이하, 잔부 Fe(철) 및 기타 불가피한 불순물을 포함하고, 아래 식 (1)의 값이 130 이하일 수 있다.Ferritic stainless steel with improved magnetic properties according to an embodiment of the present invention, in weight%, C: greater than 0% and 0.02% or less, N: greater than 0% and 0.02% or less, Si: 0.5% or more and 2.0% or less, Mn: 0.1% or more and 0.3% or less, Cr: 16.0% or more and 20.1% or less, Mo: 1.0% or more and 2.0% or less, Ti: 0.1% or more and 0.4% or less, the remainder including Fe (iron) and other unavoidable impurities, including the following The value of Equation (1) may be 130 or less.
식 (1): 30 + 2500 * ([C] + [N]) - 15 * [Si] + 2.5 * [Cr] + 22 * [Mo]Equation (1): 30 + 2500 * ([C] + [N]) - 15 * [Si] + 2.5 * [Cr] + 22 * [Mo]
식 (1)에서, [C], [N], [Si], [Cr], [Mo]는 각 원소의 함량(중량%)을 의미한다.In formula (1), [C], [N], [Si], [Cr], and [Mo] mean the content (wt%) of each element.
또한, 본 발명의 일 실시예에 따른 자기적 성질이 향상된 페라이트계 스테인리스강은, 아래 식 (2)의 값이 50 이하일 수 있다.In addition, the ferritic stainless steel having improved magnetic properties according to an embodiment of the present invention may have a value of 50 or less in Equation (2) below.
식 (2): 18 + 800 * ([C] + [N]) - 6 * [Si] + [Cr] + 6 * [Mo]Equation (2): 18 + 800 * ([C] + [N]) - 6 * [Si] + [Cr] + 6 * [Mo]
식 (2)에서, [C], [N], [Si], [Cr], [Mo]는 각 원소의 함량(중량%)을 의미한다.In formula (2), [C], [N], [Si], [Cr], and [Mo] mean the content (wt%) of each element.
또한, 본 발명의 일 실시예에 따른 자기적 성질이 향상된 페라이트계 스테인리스강은, 중량%로, Nb: 0% 초과 0.1% 이하 및 Sn: 0% 초과 0.1% 이하를 더 포함할 수 있다.In addition, the ferritic stainless steel with improved magnetic properties according to an embodiment of the present invention may further include Nb: more than 0% and less than 0.1% and Sn: more than 0% and less than 0.1%, in weight%.
또한, 본 발명의 일 실시예에 따른 자기적 성질이 향상된 페라이트계 스테인리스강은, 50Hz 주파수 대역에서 최대 투자율(magnetic permeability)이 1,000 이상일 수 있다.In addition, the ferritic stainless steel having improved magnetic properties according to an embodiment of the present invention may have a maximum magnetic permeability of 1,000 or more in a 50Hz frequency band.
또한, 본 발명의 일 실시예에 따른 자기적 성질이 향상된 페라이트계 스테인리스강은, 최대 투자율을 나타내기 위한 외부 인가 자기장이 130 A/m 이하일 수 있다.In addition, the ferritic stainless steel having improved magnetic properties according to an embodiment of the present invention may have an externally applied magnetic field of 130 A/m or less to exhibit maximum magnetic permeability.
또한, 본 발명의 일 실시예에 따른 자기적 성질이 향상된 페라이트계 스테인리스강은, 50Hz 주파수 대역에서 최대 투자율을 나타내는 조건에서의 보자력이 50 A/m 미만일 수 있다.In addition, the ferritic stainless steel having improved magnetic properties according to an embodiment of the present invention may have a coercive force of less than 50 A/m under conditions of maximum magnetic permeability in a 50 Hz frequency band.
또한, 본 발명의 일 실시예에 따른 자기적 성질이 향상된 페라이트계 스테인리스강은, 공식전위값이 300mV 이상일 수 있다.In addition, the ferritic stainless steel having improved magnetic properties according to an embodiment of the present invention may have a pitting potential value of 300 mV or more.
또한, 본 발명의 일 실시예에 따른 자기적 성질이 향상된 페라이트계 스테인리스강은, 경도가 Hv 140 이상일 수 있다.In addition, the ferritic stainless steel having improved magnetic properties according to an embodiment of the present invention may have a hardness of Hv 140 or more.
또한, 본 발명의 일 실시예에 따른 자기적 성질이 향상된 페라이트계 스테인리스강의 제조방법은, 중량%로, C: 0% 초과 0.02% 이하, N: 0% 초과 0.02% 이하, Si: 0.5% 이상 2.0% 이하, Mn: 0.1% 이상 0.3% 이하, Cr: 16.0% 이상 20.1% 이하, Mo: 1.0% 초과 2.0% 이하, Ti: 0.1% 이상 0.4% 이하, 잔부 Fe(철) 및 기타 불가피한 불순물을 포함하고, 아래 식 (1)의 값이 130 이하이고, 아래 식 (2)의 값이 50 이하인, 슬라브를 제조하는 단계; 상기 슬라브를 재가열온도 1050 내지 1150℃에서 열간압연하여 열간압연재를 제조하는 단계; 상기 열간압연재를 냉간압연하여 냉간압연재를 제조하는 단계; 및 상기 냉간압연재를 1050 내지 1150℃에서 최종 소둔하는 단계를 포함할 수 있다.In addition, in the manufacturing method of ferritic stainless steel with improved magnetic properties according to an embodiment of the present invention, in weight%, C: more than 0% and 0.02% or less, N: more than 0% and 0.02% or less, Si: 0.5% or more 2.0% or less, Mn: 0.1% or more and 0.3% or less, Cr: 16.0% or more and 20.1% or less, Mo: 1.0% or more and 2.0% or less, Ti: 0.1% or more and 0.4% or less, the balance Fe (iron) and other unavoidable impurities Including, the value of formula (1) below is 130 or less, the value of formula (2) below is 50 or less, manufacturing a slab; Preparing a hot-rolled material by hot-rolling the slab at a reheating temperature of 1050 to 1150 ° C; Cold-rolling the hot-rolled material to produce a cold-rolled material; and final annealing the cold-rolled material at 1050 to 1150 °C.
식 (1): 30 + 2500 * ([C] + [N]) - 15 * [Si] + 2.5 * [Cr] + 22 * [Mo]Equation (1): 30 + 2500 * ([C] + [N]) - 15 * [Si] + 2.5 * [Cr] + 22 * [Mo]
식 (1)에서, [C], [N], [Si], [Cr], [Mo]는 각 원소의 함량(중량%)을 의미한다.In formula (1), [C], [N], [Si], [Cr], and [Mo] mean the content (wt%) of each element.
식 (2): 18 + 800 * ([C] + [N]) - 6 * [Si] + [Cr] + 6 * [Mo]Equation (2): 18 + 800 * ([C] + [N]) - 6 * [Si] + [Cr] + 6 * [Mo]
식 (2)에서, [C], [N], [Si], [Cr], [Mo]는 각 원소의 함량(중량%)을 의미한다.In formula (2), [C], [N], [Si], [Cr], and [Mo] mean the content (wt%) of each element.
또한, 본 발명의 일 실시예에 따른 자기적 성질이 향상된 페라이트계 스테인리스강의 제조방법에서, 상기 냉간압연은 70% 이상의 압하율로 수행할 수 있다.In addition, in the manufacturing method of ferritic stainless steel with improved magnetic properties according to an embodiment of the present invention, the cold rolling may be performed at a reduction ratio of 70% or more.
본 발명의 일 실시예에 따르면, 높은 투자율을 나타내는 성분계를 도출하여, 낮은 외부 인가 자기장에 대해 큰 투자율을 나타냄으로써 전자파 차폐에 대한 반응성을 증가시킨, 자기적 성질이 향상된 페라이트계 스테인리스강 및 그 제조방법을 제공할 수 있다.According to one embodiment of the present invention, a ferritic stainless steel with improved magnetic properties, which has increased reactivity to electromagnetic wave shielding by deriving a component system exhibiting high permeability and exhibiting a large permeability to a low externally applied magnetic field, and manufacturing thereof method can be provided.
본 발명의 일 실시예에 따른 자기적 성질이 향상된 페라이트계 스테인리스강은, 중량%로, C: 0% 초과 0.02% 이하, N: 0% 초과 0.02% 이하, Si: 0.5% 이상 2.0% 이하, Mn: 0.1% 이상 0.3% 이하, Cr: 16.0% 이상 20.1% 이하, Mo: 1.0% 초과 2.0% 이하, Ti: 0.1% 이상 0.4% 이하, 잔부 Fe(철) 및 기타 불가피한 불순물을 포함하고, 아래 식 (1)의 값이 130 이하일 수 있다.Ferritic stainless steel with improved magnetic properties according to an embodiment of the present invention, in weight%, C: greater than 0% and 0.02% or less, N: greater than 0% and 0.02% or less, Si: 0.5% or more and 2.0% or less, Mn: 0.1% or more and 0.3% or less, Cr: 16.0% or more and 20.1% or less, Mo: 1.0% or more and 2.0% or less, Ti: 0.1% or more and 0.4% or less, the remainder including Fe (iron) and other unavoidable impurities, including the following The value of Equation (1) may be 130 or less.
식 (1): 30 + 2500 * ([C] + [N]) - 15 * [Si] + 2.5 * [Cr] + 22 * [Mo]Equation (1): 30 + 2500 * ([C] + [N]) - 15 * [Si] + 2.5 * [Cr] + 22 * [Mo]
식 (1)에서, [C], [N], [Si], [Cr], [Mo]는 각 원소의 함량(중량%)을 의미한다.In formula (1), [C], [N], [Si], [Cr], and [Mo] mean the content (wt%) of each element.
이하에서는 본 발명의 실시 예를 첨부 도면을 참조하여 상세히 설명한다. 이하의 실시 예는 본 발명이 속하는 기술분야에서 통상의 지식을 가진 자에게 본 발명의 사상을 충분히 전달하기 위해 제시하는 것이다. 본 발명은 여기서 제시한 실시 예만으로 한정되지 않고 다른 형태로 구체화될 수도 있다. 명세서 전체에서, 어떤 부분이 어떤 구성요소를 "포함"한다고 할 때, 이는 특별히 반대되는 기재가 없는 한 다른 구성요소를 제외하는 것이 아니라 다른 구성요소를 더 포함할 수 있는 것을 의미한다.Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The following examples are presented to sufficiently convey the spirit of the present invention to those skilled in the art. The present invention may be embodied in other forms without being limited to only the embodiments presented herein. Throughout the specification, when a certain component is said to "include", it means that it may further include other components without excluding other components unless otherwise stated.
단수의 표현은 문맥상 명백하게 예외가 있지 않는 한, 복수의 표현을 포함한다.Expressions in the singular number include plural expressions unless the context clearly dictates otherwise.
본 발명의 일 실시예에 따른 자기적 성질이 향상된 페라이트계 스테인리스강은, 중량%로, C: 0% 초과 0.02% 이하, N: 0% 초과 0.02% 이하, Si: 0.5% 이상 2.0% 이하, Mn: 0.1% 이상 0.3% 이하, Cr: 16.0% 이상 20.1% 이하, Mo: 1.0% 초과 2.0% 이하, Ti: 0.1% 이상 0.4% 이하, 잔부 Fe(철) 및 기타 불가피한 불순물을 포함할 수 있다.Ferritic stainless steel with improved magnetic properties according to an embodiment of the present invention, in weight%, C: greater than 0% and 0.02% or less, N: greater than 0% and 0.02% or less, Si: 0.5% or more and 2.0% or less, Mn: 0.1% or more and 0.3% or less, Cr: 16.0% or more and 20.1% or less, Mo: 1.0% or more and 2.0% or less, Ti: 0.1% or more and 0.4% or less, the balance may include Fe (iron) and other unavoidable impurities .
이하, 본 발명의 실시예에서의 합함금성분 함량의 수치 한정 이유에 대하여 설명한다. 이하에서는 특별한 언급이 없는 한 단위는 중량%이다.Hereinafter, the reason for limiting the numerical value of the alloy component content in the embodiments of the present invention will be described. Hereinafter, unless otherwise specified, units are % by weight.
C(탄소)의 함량은 0% 초과 0.02% 이하일 수 있다.The content of C (carbon) may be greater than 0% and 0.02% or less.
C는 강 중에 불가피하게 포함되는 불순물 원소이므로, 가급적 그 함량을 낮추는 것이 바람직하다. C의 함량이 과다한 경우에는, 탄화물 형성에 의한 자기특성 열화가 발생하므로 투자율이 열위해질 수 있다. 또한, C의 함량이 과다한 경우에는, 불순물이 증가하여 연신율이 저하되며, 가공경화지수 n값이 하락하고, 연성-취성 천이온도(DBTT, ductile to brittle transition temperature)가 증가하여 충격특성이 저하된다. 이를 고려하여, C 함량의 상한은 0.02%로 제한될 수 있다. 가공성 및 기계적 특성을 고려하여, C 함량의 상한은 바람직하게는 0.01중량%로 제한될 수 있다.Since C is an impurity element inevitably contained in steel, it is desirable to lower its content as much as possible. When the content of C is excessive, since magnetic properties deteriorate due to formation of carbides, magnetic permeability may deteriorate. In addition, when the content of C is excessive, the elongation rate decreases due to the increase in impurities, the strain hardening index n value decreases, and the ductile to brittle transition temperature (DBTT) increases, resulting in a decrease in impact properties. . Considering this, the upper limit of the C content may be limited to 0.02%. Considering processability and mechanical properties, the upper limit of the C content may preferably be limited to 0.01% by weight.
N(질소)의 함량은 0% 초과 0.02% 이하일 수 있다.The content of N (nitrogen) may be more than 0% and 0.02% or less.
N의 함량이 과다한 경우에는, 소재의 불순물이 증가하여 연신율이 저하되며, 연성-취성 천이온도(DBTT, ductile to brittle transition temperature)가 증가하여 충격특성이 저하된다. 또한, N의 함량이 과다한 경우에는, 막대형의 AlN 석출물을 형성하여, 결정립 미세화를 야기함으로써 철손이 열위하게 된다. 이를 고려하여, N 함량의 상한은 0.02%로 제한될 수 있다. 가공성 및 기계적 특성을 고려하여, N 함량의 상한은 바람직하게는 0.015중량%로 제한될 수 있다.When the content of N is excessive, the elongation rate is lowered due to the increase in impurities of the material, and the ductile-to-brittle transition temperature (DBTT) is increased, thereby degrading the impact properties. In addition, when the N content is excessive, rod-shaped AlN precipitates are formed, resulting in crystal grain refinement, resulting in inferior iron loss. Considering this, the upper limit of the N content may be limited to 0.02%. Considering processability and mechanical properties, the upper limit of the N content may preferably be limited to 0.015% by weight.
Si(실리콘)의 함량은 0.5% 이상 2.0% 이하일 수 있다.The content of Si (silicon) may be 0.5% or more and 2.0% or less.
Si은 낮은 외부 인가 자기장에 대하여 투자율의 증가를 구현하는데 효과적인 원소이다. 이를 고려하여, Si는 0.5% 이상 첨가될 수 있다. 그러나, Si의 함량이 과다한 경우에는, 연신율이 저하되며, 가공경화지수 n값이 하락하고, Si계 개재물이 증가하여 가공성이 저하된다. 이를 고려하여, Si 함량의 상한은 2.0%로 제한될 수 있다. 가공성을 고려하여, Si 함량의 상한은 바람직하게는 1.0중량%로 제한될 수 있다.Si is an element effective in realizing an increase in magnetic permeability with respect to a low externally applied magnetic field. Considering this, Si may be added in an amount of 0.5% or more. However, when the content of Si is excessive, the elongation is lowered, the strain hardening index n value is lowered, and the Si-based inclusions are increased, resulting in lower workability. Considering this, the upper limit of the Si content may be limited to 2.0%. Considering workability, the upper limit of the Si content may preferably be limited to 1.0% by weight.
Mn(망간)의 함량은 0.1% 이상 0.3% 이하일 수 있다.The content of Mn (manganese) may be 0.1% or more and 0.3% or less.
Mn의 함량이 낮은 경우에는, 미세한 MnS 석출물이 형성되어 결정립 미세화를 야기함으로써 자성을 약화시킨다. 따라서, MnS 석출물이 조대하게 형성될 수 있도록 Mn은 0.1% 이상 첨가될 수 있다. 그러나, Mn의 함량이 과다한 경우에는, MnS 석출물 분율의 증가로 인해 자성이 열위해질 수 있다. 이를 고려하여, Mn 함량의 상한은 0.3%로 제한될 수 있다.When the content of Mn is low, fine MnS precipitates are formed to cause crystal grain refinement, thereby weakening the magnetism. Therefore, Mn may be added in an amount of 0.1% or more so that MnS precipitates can be coarsely formed. However, when the Mn content is excessive, magnetic properties may be deteriorated due to an increase in the MnS precipitate fraction. Considering this, the upper limit of the Mn content may be limited to 0.3%.
Cr(크롬)의 함량은 16.0% 이상 20.1% 이하일 수 있다.The content of Cr (chromium) may be 16.0% or more and 20.1% or less.
Cr은 산화성 환경에서 부동태 피막을 형성하여 내식성을 향상시키는 원소이다. 이를 고려하여 Cr은 16.0% 이상 첨가될 수 있다. 그러나, Cr의 함량이 과다할 경우에는, 슬라브 내 델타(δ) 페라이트 형성을 조장하여 연신율 및 충격인성이 저하되고, 투자율이 떨어진다. 이를 고려하여, Cr 함량의 상한은 20.1%로 제한될 수 있다.Cr is an element that improves corrosion resistance by forming a passivation film in an oxidizing environment. In consideration of this, 16.0% or more of Cr may be added. However, when the Cr content is excessive, it promotes the formation of delta (δ) ferrite in the slab, resulting in lower elongation and impact toughness, and lower permeability. Considering this, the upper limit of the Cr content may be limited to 20.1%.
Mo(몰리브덴)의 함량은 1.0% 초과 2.0% 이하일 수 있다.The content of Mo (molybdenum) may be greater than 1.0% and less than or equal to 2.0%.
Mo은 스테인리스강의 내식성을 증가시키는데 효과적인 원소이다. 이를 고려하여 1.0% 이상 첨가될 수 있다. 그러나, Mo의 함량이 과다한 경우에는, 결정립계에 편석되어 결정립 성장을 억제하는 역할을 함으로써 결정립 미세화를 야기하므로, 자성이 열위해질 수 있다. 이를 고려하여, Mo 함량의 상한은 2.0%로 제한될 수 있다.Mo is an element effective in increasing the corrosion resistance of stainless steel. In consideration of this, 1.0% or more may be added. However, when the content of Mo is excessive, it is segregated at the grain boundary and plays a role of suppressing grain growth, thereby causing crystal grain refinement, so that magnetism may be inferior. Considering this, the upper limit of the Mo content may be limited to 2.0%.
Ti(티타늄)의 함량은 0.1% 이상 0.4% 이하일 수 있다.The content of Ti (titanium) may be 0.1% or more and 0.4% or less.
Ti은 석출현상을 일으켜 강도를 향상시키는데 효과적인 원소이다. 이를 고려하여, Ti는 0.1% 이상 첨가될 수 있다. 그러나, Ti의 함량이 과다한 경우에는, Ti계 석출물이 과도하게 늘어나 결정립 크기가 충분히 커지지 않으므로 투자율이 하락하는 문제가 발생한다. 이를 고려하여, Ti 함량의 상한은 0.4%로 제한될 수 있다.Ti is an effective element for improving strength by causing precipitation. Considering this, Ti may be added in an amount of 0.1% or more. However, when the content of Ti is excessive, the Ti-based precipitate is excessively increased and the crystal grain size does not become sufficiently large, resulting in a decrease in magnetic permeability. Considering this, the upper limit of the Ti content may be limited to 0.4%.
본 발명의 나머지 성분은 철(Fe)이다. 다만, 통상의 제조과정에서는 원료 또는 주위 환경으로부터 의도되지 않는 불순물들이 불가피하게 혼입될 수 있으므로, 이를 배제할 수는 없다. 이들 불순물들은 통상의 제조과정의 기술자라면 누구라도 알 수 있는 것이기 때문에 그 모든 내용을 특별히 본 명세서에서 언급하지는 않는다.The remaining component of the present invention is iron (Fe). However, since unintended impurities from raw materials or the surrounding environment may inevitably be mixed in a normal manufacturing process, this cannot be excluded. Since these impurities are known to anyone skilled in the ordinary manufacturing process, not all of them are specifically mentioned in this specification.
또한, 본 발명의 일 실시예에 따른 자기적 성질이 향상된 페라이트계 스테인리스강은, 중량%로, Nb: 0% 초과 0.1% 이하 및 Sn: 0% 초과 0.1% 이하를 더 포함할 수 있다.In addition, the ferritic stainless steel with improved magnetic properties according to an embodiment of the present invention may further include Nb: more than 0% and less than 0.1% and Sn: more than 0% and less than 0.1%, in weight%.
Nb(니오븀)의 함량은 0% 초과 0.1% 이하일 수 있다.The content of Nb (niobium) may be greater than 0% and less than or equal to 0.1%.
Nb은 Ti과 같이 미세 석출상을 형성하는 원소이다. 다만, Ti은 상대적으로 고온상을 형성하므로, 열처리에 의해 미세 석출을 방지할 수 있지만, Nb은 비교적 낮은 온도에서 안정한 상을 형성하므로, 열연 중 재고용되고, 소둔 시 미세 석출을 일으킬 수 있다. 따라서, Nb의 함량이 과도한 경우에는, 미세 석출로 인한 자성 저하가 발생할 수 있으므로, 불순물로 관리하는 것이 바람직하다. 이를 고려하여, Nb 함량의 상한은 0.1%로 제한될 수 있다. Nb is an element that forms a fine precipitated phase like Ti. However, since Ti forms a relatively high-temperature phase, fine precipitation can be prevented by heat treatment, but since Nb forms a stable phase at a relatively low temperature, it is re-dissolved during hot rolling and may cause fine precipitation during annealing. Therefore, when the content of Nb is excessive, magnetic deterioration due to fine precipitation may occur, so it is preferable to manage it as an impurity. Considering this, the upper limit of the Nb content may be limited to 0.1%.
Sn(주석)의 함량은 0% 초과 0.1% 이하일 수 있다.The content of Sn (tin) may be greater than 0% and 0.1% or less.
Sn은 Ti과 같이 미세 석출상을 형성하는 원소이다. 다만, Ti은 상대적으로 고온상을 형성하므로, 열처리에 의해 미세 석출을 방지할 수 있지만, Sn은 비교적 낮은 온도에서 안정한 상을 형성하므로, 열연 중 재고용되고, 소둔 시 미세 석출을 일으킬 수 있다. 따라서, Sn의 함량이 과도한 경우에는, 미세 석출로 인한 자성 저하가 발생할 수 있으므로, 불순물로 관리하는 것이 바람직하다. 이를 고려하여, Sn 함량의 상한은 0.1%로 제한될 수 있다.Sn, like Ti, is an element that forms a fine precipitated phase. However, since Ti forms a relatively high temperature phase, fine precipitation can be prevented by heat treatment, but Sn forms a stable phase at a relatively low temperature, so it is re-dissolved during hot rolling and may cause fine precipitation during annealing. Therefore, when the content of Sn is excessive, magnetic deterioration due to fine precipitation may occur, so it is preferable to manage it as an impurity. Considering this, the upper limit of the Sn content may be limited to 0.1%.
본 발명의 일 실시예에 따른 자기적 성질이 향상된 페라이트계 스테인리스강은, 아래 식 (1)의 값이 130 이하일 수 있다.In the ferritic stainless steel having improved magnetic properties according to an embodiment of the present invention, the value of Equation (1) below may be 130 or less.
식 (1): 30 + 2500 * ([C] + [N]) - 15 * [Si] + 2.5 * [Cr] + 22 * [Mo]Equation (1): 30 + 2500 * ([C] + [N]) - 15 * [Si] + 2.5 * [Cr] + 22 * [Mo]
식 (1)에서, [C], [N], [Si], [Cr], [Mo]는 각 원소의 함량(중량%)을 의미한다.In formula (1), [C], [N], [Si], [Cr], and [Mo] mean the content (wt%) of each element.
본 발명은 낮은 외부 인가 자기장에 대해 큰 투자율을 나타냄으로써 전자파 차폐에 대한 반응성을 증가시킨, 자기적 성질이 향상된 페라이트계 스테인리스강 및 그 제조방법을 제공하고자 한다. 상기 식 (1)의 값이 130을 초과하는 경우에는, 비교적 높은 외부 인가 자기장에 대해 큰 투자율 값을 나타내므로, 전자파 차폐에 대한 반응성이 떨어진다. 따라서, 상기 식 (1)의 값은 130 이하상일 수 있다.An object of the present invention is to provide a ferritic stainless steel with improved magnetic properties and a method for manufacturing the same, which has increased reactivity to electromagnetic shielding by exhibiting a large magnetic permeability to a low externally applied magnetic field. When the value of Equation (1) exceeds 130, since it shows a large permeability value with respect to a relatively high externally applied magnetic field, the reactivity to electromagnetic wave shielding is poor. Therefore, the value of Equation (1) may be 130 or less.
상기 식 (1)의 값을 130 이하로 제어함으로써, 본 발명의 일 실시예에 따른 자기적 성질이 향상된 페라이트계 스테인리스강은, 50Hz 주파수 대역에서 최대 투자율(magnetic permeability)이 1,000 이상일 수 있다. 또한, 최대 투자율을 나타내기 위한 외부 인가 자기장이 130 A/m 이하일 수 있다.By controlling the value of Equation (1) to 130 or less, the ferritic stainless steel with improved magnetic properties according to an embodiment of the present invention may have a maximum magnetic permeability of 1,000 or more in a 50Hz frequency band. In addition, the externally applied magnetic field for showing the maximum magnetic permeability may be 130 A/m or less.
본 발명의 일 실시예에 따른 자기적 성질이 향상된 페라이트계 스테인리스강은, 아래 식 (2)의 값이 50 이하일 수 있다.In the ferritic stainless steel having improved magnetic properties according to an embodiment of the present invention, the value of Equation (2) below may be 50 or less.
식 (2): 18 + 800 * ([C] + [N]) - 6 * [Si] + [Cr] + 6 * [Mo]Equation (2): 18 + 800 * ([C] + [N]) - 6 * [Si] + [Cr] + 6 * [Mo]
식 (2)에서, [C], [N], [Si], [Cr], [Mo]는 각 원소의 함량(중량%)을 의미한다.In formula (2), [C], [N], [Si], [Cr], and [Mo] mean the content (wt%) of each element.
보자력이란, 자화된 자성체를 자화되지 않은 상태로 되돌리기 위해 필요한 역방향의 외부 자장의 크기를 말한다. 상기 식 (2)의 값이 50을 초과하는 경우에는, 보자력이 높아지므로 차폐능이 열위해질 수 있다. 따라서, 상기 식 (2)의 값은 50 이하일 수 있다.The coercive force refers to the magnitude of an external magnetic field in a reverse direction required to return a magnetized magnetic material to a non-magnetized state. When the value of Equation (2) exceeds 50, the coercive force increases, so the shielding ability may deteriorate. Therefore, the value of Equation (2) may be 50 or less.
상기 식 (2)를 50 이하로 제어함으로써, 본 발명의 일 실시예에 따른 자기적 성질이 향상된 페라이트계 스테인리스강은, 50Hz 주파수 대역에서 최대 투자율을 나타내는 조건에서의 보자력이 50A/m 미만일 수 있다.By controlling Equation (2) to 50 or less, the ferritic stainless steel with improved magnetic properties according to an embodiment of the present invention may have a coercive force of less than 50 A / m under the condition of showing the maximum magnetic permeability in the 50 Hz frequency band. .
또한, 본 발명의 일 실시예에 따른 자기적 성질이 향상된 페라이트계 스테인리스강은, 합금조성 및 제조공정을 제어하여 내식성을 향상시킴으로써, 공식전위값이 300mV 이상일 수 있다.In addition, the ferritic stainless steel with improved magnetic properties according to an embodiment of the present invention may have a pitting potential value of 300 mV or more by improving corrosion resistance by controlling the alloy composition and manufacturing process.
또한, 본 발명의 일 실시예에 따른 자기적 성질이 향상된 페라이트계 스테인리스강은, 합금조성 및 제조공정을 제어하여 강도를 향상시킴으로써, 경도가 Hv 140 이상일 수 있다.In addition, the ferritic stainless steel with improved magnetic properties according to an embodiment of the present invention may have a hardness of Hv 140 or more by improving strength by controlling the alloy composition and manufacturing process.
다음으로, 본 발명의 다른 일 측면에 따른 자기적 성질이 향상된 페라이트계 스테인리스강의 제조방법에 대하여 설명한다.Next, a method for manufacturing ferritic stainless steel having improved magnetic properties according to another aspect of the present invention will be described.
본 발명의 일 실시예에 따른 자기적 성질이 향상된 페라이트계 스테인리스강의 제조방법은, 중량%로, C: 0% 초과 0.02% 이하, N: 0% 초과 0.02% 이하, Si: 0.5% 이상 2.0% 이하, Mn: 0.1% 이상 0.3% 이하, Cr: 16.0% 이상 20.1% 이하, Mo: 1.0% 초과 2.0% 이하, Ti: 0.1% 이상 0.4% 이하, 잔부 Fe(철) 및 기타 불가피한 불순물을 포함하고, 아래 식 (1)의 값이 130 이하이고, 아래 식 (2)의 값이 50 이하인, 슬라브를 제조하는 단계; 상기 슬라브를 재가열온도 1050 내지 1150℃에서 열간압연하여 열간압연재를 제조하는 단계; 상기 열간압연재를 냉간압연하여 냉간압연재를 제조하는 단계; 및 상기 냉간압연재를 1050 내지 1150℃에서 최종 소둔하는 단계를 포함할 수 있다.In the manufacturing method of ferritic stainless steel with improved magnetic properties according to an embodiment of the present invention, in weight%, C: more than 0% and 0.02% or less, N: more than 0% and 0.02% or less, Si: 0.5% or more and 2.0% Hereinafter, Mn: 0.1% or more and 0.3% or less, Cr: 16.0% or more and 20.1% or less, Mo: more than 1.0% and 2.0% or less, Ti: 0.1% or more and 0.4% or less, the balance including Fe (iron) and other unavoidable impurities, , Manufacturing a slab in which the value of Equation (1) below is 130 or less and the value of Equation (2) below is 50 or less; Preparing a hot-rolled material by hot-rolling the slab at a reheating temperature of 1050 to 1150 ° C; Cold-rolling the hot-rolled material to produce a cold-rolled material; and final annealing the cold-rolled material at 1050 to 1150 °C.
식 (1): 30 + 2500 * ([C] + [N]) - 15 * [Si] + 2.5 * [Cr] + 22 * [Mo]Equation (1): 30 + 2500 * ([C] + [N]) - 15 * [Si] + 2.5 * [Cr] + 22 * [Mo]
식 (1)에서, [C], [N], [Si], [Cr], [Mo]는 각 원소의 함량(중량%)을 의미한다.In formula (1), [C], [N], [Si], [Cr], and [Mo] mean the content (wt%) of each element.
식 (2): 18 + 800 * ([C] + [N]) - 6 * [Si] + [Cr] + 6 * [Mo]Equation (2): 18 + 800 * ([C] + [N]) - 6 * [Si] + [Cr] + 6 * [Mo]
식 (2)에서, [C], [N], [Si], [Cr], [Mo]는 각 원소의 함량(중량%)을 의미한다.In formula (2), [C], [N], [Si], [Cr], and [Mo] mean the content (wt%) of each element.
상기 각 합금조성의 성분 범위 및 성분 관계식의 수치 한정 이유는 상술한 바와 같으며, 이하 각 제조단계에 대하여 보다 상세히 설명한다.The reason for limiting the numerical range of the component range and component relational expression of each alloy composition is as described above, and each manufacturing step will be described in detail below.
먼저, 상기 합금조성 및 성분 관계식을 만족하는 슬라브를 제조한 후, 일련의 열간압연, 냉간압연 및 최종 소둔하는 공정을 거칠 수 있다.First, after manufacturing a slab satisfying the alloy composition and component relational expression, a series of hot rolling, cold rolling, and final annealing may be performed.
상기 슬라브는 재가열온도 1050 내지 1150℃에서 열간압연 할 수 있다.The slab may be hot rolled at a reheating temperature of 1050 to 1150 ° C.
슬라브의 재가열온도가 너무 낮으면, 압연롤의 부하가 커질 수 있고, 슬라브 주조 중 생성된 조대한 석출물을 재분해하기 어려울 수 있고, 내부 조직이 균질화되기 어렵다. 이를 고려하여 슬라브의 재가열온도는 1050℃ 이상일 수 있다. 그러나, 재가열온도가 너무 높으면, 슬라브의 결정립 직경이 지나치게 조대화되어 강도가 열위해질 수 있다. 이를 고려하여, 슬라브의 재가열온도의 상한은 1150℃로 제한될 수 있다.If the reheating temperature of the slab is too low, the load on the rolling rolls may increase, it may be difficult to re-disassemble the coarse precipitates generated during casting of the slab, and it may be difficult to homogenize the internal structure. In consideration of this, the reheating temperature of the slab may be 1050 ° C or higher. However, if the reheating temperature is too high, the grain diameter of the slab may be excessively coarsened, resulting in inferior strength. Considering this, the upper limit of the reheating temperature of the slab may be limited to 1150 ° C.
상기 냉간압연은 70% 이상의 압하율로 수행할 수 있다. 압하율이 70% 미만인 경우에는 목적하는 강도를 달성하기 어려울 수 있다.The cold rolling may be performed at a reduction ratio of 70% or more. If the reduction ratio is less than 70%, it may be difficult to achieve the desired strength.
상기 냉간압연재는 1050 내지 1150℃에서 최종 소둔할 수 있다.The cold-rolled material may be final annealed at 1050 to 1150 ° C.
최종 소둔온도가 낮으면, 장시간이 소요되어 제조비용이 증가할 수 있다. 이를 고려하여, 최종 소둔온도는 1050℃이상일 수 있다. 그러나, 최종 소둔온도가 높으면, 미세조직이 지나치게 조대화될 수 있어 기계적 성질이 열위해 질 수 있다. 이를 고려하여, 최종 소둔온도는 1150℃이하일 수 있다.If the final annealing temperature is low, it takes a long time, and manufacturing cost may increase. Considering this, the final annealing temperature may be 1050 ℃ or more. However, if the final annealing temperature is high, the microstructure may be excessively coarse, and mechanical properties may be deteriorated. Considering this, the final annealing temperature may be 1150 °C or less.
이하, 본 발명을 실시예를 통하여 보다 상세하게 설명한다. 그러나, 이러한 실시예의 기재는 본 발명의 실시를 예시하기 위한 것일 뿐 이러한 실시예의 기재에 의하여 본 발명이 제한되는 것은 아니다. 본 발명의 권리범위는 특허청구범위에 기재된 사항과 이로부터 합리적으로 유추되는 사항에 의하여 결정되는 것이기 때문이다.Hereinafter, the present invention will be described in more detail through examples. However, the description of these examples is only for exemplifying the practice of the present invention, and the present invention is not limited by the description of these examples. This is because the scope of the present invention is determined by the matters described in the claims and the matters reasonably inferred therefrom.
{실시예}{Example}
아래 표 1에 나타낸 다양한 화학 조성을 가지는 강을 슬라브로 주조하며, 주조된 슬라브를 1050℃로 재가열하였다. 재가열된 슬라브를 열간 압연하고, 70%의 압하율로 냉간 압연한 후, 1050℃ 온도에서 소둔하여 최종 냉연 제품으로 제조하였다.Steels having various chemical compositions shown in Table 1 below were cast into slabs, and the cast slabs were reheated to 1050 ° C. The reheated slab was hot-rolled, cold-rolled at a reduction ratio of 70%, and then annealed at a temperature of 1050° C. to produce a final cold-rolled product.
CC | NN | SiSi | MnMn | CrCr | MoMo | TiTi | |
실시예1Example 1 | 0.0050.005 | 0.0070.007 | 0.500.50 | 0.180.18 | 17.817.8 | 1.11.1 | 0.340.34 |
실시예2Example 2 | 0.0060.006 | 0.0070.007 | 0.990.99 | 0.200.20 | 17.817.8 | 1.11.1 | 0.320.32 |
실시예3Example 3 | 0.0180.018 | 0.0060.006 | 2.002.00 | 0.200.20 | 17.017.0 | 1.11.1 | 0.310.31 |
실시예4Example 4 | 0.0060.006 | 0.0060.006 | 1.921.92 | 0.200.20 | 17.717.7 | 1.11.1 | 0.120.12 |
실시예5Example 5 | 0.0050.005 | 0.0070.007 | 1.031.03 | 0.190.19 | 20.120.1 | 1.11.1 | 0.290.29 |
실시예6Example 6 | 0.0050.005 | 0.0080.008 | 0.980.98 | 0.200.20 | 20.020.0 | 1.11.1 | 0.290.29 |
실시예7Example 7 | 0.0050.005 | 0.0070.007 | 1.031.03 | 0.200.20 | 17.817.8 | 1.71.7 | 0.290.29 |
비교예1Comparative Example 1 | 0.0060.006 | 0.0080.008 | 0.120.12 | 0.200.20 | 17.717.7 | 1.11.1 | 0.250.25 |
비교예2Comparative Example 2 | 0.0060.006 | 0.0070.007 | 0.300.30 | 0.210.21 | 18.318.3 | 1.81.8 | 0.080.08 |
비교예3Comparative Example 3 | 0.0050.005 | 0.0080.008 | 0.850.85 | 0.200.20 | 17.717.7 | 1.81.8 | 0.280.28 |
비교예4Comparative Example 4 | 0.0390.039 | 0.0170.017 | 0.390.39 | 0.330.33 | 17.117.1 | 0.00.0 | 0.000.00 |
비교예5Comparative Example 5 | 0.0110.011 | 0.0180.018 | 0.340.34 | 0.210.21 | 21.021.0 | 0.00.0 | 0.000.00 |
식 (1) 및 식 (2)의 값, 최대 투자율, 인가 자기장, 보자력, 공식전위 및 경도는 아래 표2에 나타냈다.식 (1) 값은 30 + 2500 * ([C] + [N]) - 15 * [Si] + 2.5 * [Cr] + 22 * [Mo]의 계산값이다.The values of equation (1) and equation (2), maximum magnetic permeability, applied magnetic field, coercive force, pit potential and hardness are shown in Table 2 below. The value of equation (1) is 30 + 2500 * ([C] + [N]) - This is the calculated value of 15 * [Si] + 2.5 * [Cr] + 22 * [Mo].
상기 식 (1)에서, [C], [N], [Si], [Cr], [Mo]는 각 원소의 함량(중량%)을 의미한다.In the above formula (1), [C], [N], [Si], [Cr], [Mo] means the content (wt%) of each element.
식 (2) 값은 18 + 800 * ([C] + [N]) - 6 * [Si] + [Cr] + 6 * [Mo]의 계산값이다.The value of equation (2) is a calculated value of 18 + 800 * ([C] + [N]) - 6 * [Si] + [Cr] + 6 * [Mo].
상기 식 (2)에서, [C], [N], [Si], [Cr], [Mo]는 각 원소의 함량(중량%)을 의미한다.In the above formula (2), [C], [N], [Si], [Cr], [Mo] means the content (wt%) of each element.
최종 냉연 제품에 대하여, 50Hz 주파수 대역에서 외부 인가 자기장을 서서히 증가시키면서 소재의 자화에 의한 자기장을 측정함으로써 자기적 성질을 평가했다.For the final cold-rolled product, the magnetic properties were evaluated by measuring the magnetic field due to the magnetization of the material while gradually increasing the externally applied magnetic field in a 50 Hz frequency band.
최대 투자율은 모델명이 Ferropro FP-5인 비자성 투자율 측정기를 이용하여, 직경 20mm 이상, 두께 5mm 이상인 강 샘플 단면에 대해 프로브를 접촉하여 측정했다.The maximum magnetic permeability was measured using a non-magnetic magnetic permeability meter having a model name of Ferropro FP-5 by contacting a probe to a cross section of a steel sample having a diameter of 20 mm or more and a thickness of 5 mm or more.
공식 전위(pitting potential)는 NaCl 용액에 침지하고 전위를 인가하여 공식이 발생하는 전위 (pitting potential)를 측정한 값을 나타냈다. 여기서, 상기 NaCl용액의 온도는 30℃이고, 농도는 3.5% 로 설정했다.The pitting potential represents a value measured by immersing in a NaCl solution and applying a potential to generate pitting potential. Here, the temperature of the NaCl solution was set to 30 °C and the concentration was set to 3.5%.
경도는 Zwick Roell사의 비커스 경도 측정기를 통해 측정했다.Hardness was measured using a Vickers hardness tester from Zwick Roell.
식 (1)Equation (1) | 식 (2)Equation (2) | 최대 투자율permeability | 인가 자기장(A/m)Applied magnetic field (A/m) | 보자력 (A/m)Coercivity (A/m) | 공식전위 (mV)Potential potential (mV) | 경도(Hv)Hardness (Hv) | |
실시예1Example 1 | 121.2121.2 | 4949 | 17371737 | 122122 | 4848 | 362362 | 146146 |
실시예2Example 2 | 116.4116.4 | 46.946.9 | 13861386 | 120120 | 4545 | 365365 | 163163 |
실시예3Example 3 | 126.7126.7 | 48.848.8 | 20202020 | 128128 | 4747 | 483483 | 193193 |
실시예4Example 4 | 99.799.7 | 40.440.4 | 19011901 | 100100 | 4040 | 459459 | 190190 |
실시예5Example 5 | 119119 | 48.148.1 | 20082008 | 120120 | 4747 | 499499 | 168168 |
실시예6Example 6 | 122122 | 49.149.1 | 19211921 | 120120 | 4848 | 482482 | 166166 |
실시예7Example 7 | 126.5126.5 | 49.449.4 | 15711571 | 129129 | 4949 | 462462 | 171171 |
비교예1Comparative Example 1 | 131.7131.7 | 52.852.8 | 16531653 | 133133 | 5252 | 317317 | 140140 |
비교예2Comparative Example 2 | 143.4143.4 | 55.755.7 | 14931493 | 160160 | 6565 | 461461 | 165165 |
비교예3Comparative Example 3 | 133.6133.6 | 51.851.8 | 14191419 | 132132 | 5050 | 450450 | 169169 |
비교예4Comparative Example 4 | 206.9206.9 | 77.677.6 | 15891589 | 200200 | 8888 | 278278 | 162162 |
비교예5Comparative Example 5 | 149.9149.9 | 60.260.2 | 17381738 | 183183 | 8787 | 362362 | 160160 |
표 2를 참조하면, 실시예 1 내지 7은 모두 식 (1)의 값이 130 이하이고, 식 (2)의 값이 50 이하를 만족했다. 따라서, 50Hz 주파수 대역에서 최대 투자율(magnetic permeability)이 1,000 이상이고, 최대 투자율을 나타내기 위한 외부 인가 자기장이 130 A/m 이하이고, 최대 투자율을 나타내는 조건에서의 보자력이 50A/m 미만을 만족했다. 즉, 실시예 1 내지 7은 낮은 외부 인가 자기장에 대해 큰 투자율을 나타냄으로써 전자파 차폐에 대한 반응성이 증대되어 자기적 성질이 향상되었음을 알 수 있다. 또한, 실시예 1 내지 7은 공식전위 값이 300mV 이상이고, 경도가 Hv 140 이상을 만족했다. 즉, 실시예 1 내지 7은 내식성 및 강도가 우수했다.Referring to Table 2, Examples 1 to 7 all satisfied the value of Equation (1) of 130 or less and the value of Equation (2) of 50 or less. Therefore, the maximum magnetic permeability in the 50Hz frequency band was 1,000 or more, the externally applied magnetic field to indicate the maximum permeability was 130 A/m or less, and the coercive force was less than 50 A/m under the conditions of maximum permeability. . That is, it can be seen that Examples 1 to 7 exhibit high magnetic permeability to a low externally applied magnetic field, thereby increasing reactivity to electromagnetic wave shielding and improving magnetic properties. In addition, Examples 1 to 7 had a pitting potential value of 300 mV or more and a hardness of Hv 140 or more. That is, Examples 1 to 7 were excellent in corrosion resistance and strength.
비교예 1 내지 5는 식 (1)의 값이 130 이하를 만족하지 못했다. 따라서, 비교예 1 내지 5는 최대 투자율을 나타내기 위한 외부 인가 자기장이 130 A/m 이하를 만족하지 못했다. 또한, 비교예 1 내지 5는 식 (2)의 값이 50 이하를 만족하지 못했다. 따라서, 비교예 1 내지 5는 보자력이 50 A/m 미만을 만족하지 못했다. 즉, 비교예 1 내지 5는 외부 인가 자기장이 비교적 높으므로, 전자파 차폐에 대한 반응성이 열위했음을 알 수 있다.In Comparative Examples 1 to 5, the value of Formula (1) did not satisfy 130 or less. Accordingly, Comparative Examples 1 to 5 did not satisfy the externally applied magnetic field of 130 A/m or less to indicate the maximum magnetic permeability. In Comparative Examples 1 to 5, the value of Formula (2) did not satisfy 50 or less. Therefore, Comparative Examples 1 to 5 did not satisfy the coercive force of less than 50 A/m. That is, since Comparative Examples 1 to 5 had a relatively high externally applied magnetic field, it could be seen that their reactivity to electromagnetic wave shielding was inferior.
또한, 비교예 4는 Mo 성분을 첨가하지 않았고, 비교적 낮은 수준의 Cr 함량으로 인해 공식전위값이 300mV 이상을 만족하지 못했다. 즉, 비교예 4는 내식성이 열위했다.In Comparative Example 4, Mo component was not added, and the pitting potential value did not satisfy 300 mV or more due to the relatively low level of Cr content. That is, Comparative Example 4 was inferior in corrosion resistance.
본 발명의 일 실시예에 따르면, 높은 투자율을 나타내는 성분계를 도출하여, 낮은 외부 인가 자기장에 대해 큰 투자율을 나타냄으로써 전자파 차폐에 대한 반응성을 증가시킨, 자기적 성질이 향상된 페라이트계 스테인리스강 및 그 제조방법을 제공할 수 있는 바, 산업상 이용가능성이 인정된다.According to one embodiment of the present invention, a ferritic stainless steel with improved magnetic properties, which has increased reactivity to electromagnetic wave shielding by deriving a component system exhibiting high permeability and exhibiting a large permeability to a low externally applied magnetic field, and manufacturing thereof As a method can be provided, industrial applicability is recognized.
Claims (10)
- 중량%로, C: 0% 초과 0.02% 이하, N: 0% 초과 0.02% 이하, Si: 0.5% 이상 2.0% 이하, Mn: 0.1% 이상 0.3% 이하, Cr: 16.0% 이상 20.1% 이하, Mo: 1.0% 초과 2.0% 이하, Ti: 0.1% 이상 0.4% 이하, 잔부 Fe(철) 및 기타 불가피한 불순물을 포함하고,In weight %, C: more than 0% and 0.02% or less, N: more than 0% and 0.02% or less, Si: 0.5% or more and 2.0% or less, Mn: 0.1% or more and 0.3% or less, Cr: 16.0% or more and 20.1% or less, Mo : More than 1.0% and 2.0% or less, Ti: 0.1% or more and 0.4% or less, the balance including Fe (iron) and other unavoidable impurities,아래 식 (1)의 값이 130 이하인, 자기적 성질이 향상된 페라이트계 스테인리스강:Ferritic stainless steels with improved magnetic properties, where the value of equation (1) below is less than or equal to 130:식 (1): 30 + 2500 * ([C] + [N]) - 15 * [Si] + 2.5 * [Cr] + 22 * [Mo]Equation (1): 30 + 2500 * ([C] + [N]) - 15 * [Si] + 2.5 * [Cr] + 22 * [Mo](식 (1)에서, [C], [N], [Si], [Cr], [Mo]는 각 원소의 함량(중량%)을 의미한다).(In formula (1), [C], [N], [Si], [Cr], and [Mo] mean the content (wt%) of each element).
- 청구항 1에 있어서,The method of claim 1,아래 식 (2)의 값이 50 이하인, 자기적 성질이 향상된 페라이트계 스테인리스강:Ferritic stainless steel with improved magnetic properties, where the value of equation (2) below is 50 or less:식 (2): 18 + 800 * ([C] + [N]) - 6 * [Si] + [Cr] + 6 * [Mo]Equation (2): 18 + 800 * ([C] + [N]) - 6 * [Si] + [Cr] + 6 * [Mo](식 (2)에서, [C], [N], [Si], [Cr], [Mo]는 각 원소의 함량(중량%)을 의미한다).(In formula (2), [C], [N], [Si], [Cr], and [Mo] mean the content (% by weight) of each element).
- 청구항 1에 있어서,The method of claim 1,중량%로, Nb: 0% 초과 0.1% 이하 및 Sn: 0% 초과 0.1% 이하를 더 포함하는, 자기적 성질이 향상된 페라이트계 스테인리스강.A ferritic stainless steel with improved magnetic properties, further comprising, in weight percent, Nb: greater than 0% and not more than 0.1% and Sn: greater than 0% and not more than 0.1%.
- 청구항 1에 있어서,The method of claim 1,50Hz 주파수 대역에서 최대 투자율(magnetic permeability)이 1,000 이상인, 자기적 성질이 향상된 페라이트계 스테인리스강.Ferritic stainless steel with improved magnetic properties, with a maximum magnetic permeability of 1,000 or more in the 50Hz frequency band.
- 청구항 1에 있어서,The method of claim 1,최대 투자율을 나타내기 위한 외부 인가 자기장이 130 A/m 이하인, 자기적 성질이 향상된 페라이트계 스테인리스강.A ferritic stainless steel with improved magnetic properties, with an externally applied magnetic field of 130 A/m or less to exhibit maximum magnetic permeability.
- 청구항 1에 있어서,The method of claim 1,50Hz 주파수 대역에서 최대 투자율을 나타내는 조건에서의 보자력이 50 A/m 미만인, 자기적 성질이 향상된 페라이트계 스테인리스강.A ferritic stainless steel with improved magnetic properties, with a coercive force of less than 50 A/m under conditions of maximum magnetic permeability in the 50Hz frequency band.
- 청구항 1에 있어서,The method of claim 1,공식전위값이 300mV 이상인, 자기적 성질이 향상된 페라이트계 스테인리스강.Ferritic stainless steel with improved magnetic properties, with a pitting potential value of 300 mV or more.
- 청구항 1에 있어서,The method of claim 1,경도가 Hv 140 이상인, 자기적 성질이 향상된 페라이트계 스테인리스강.Ferritic stainless steel with improved magnetic properties, with a hardness greater than Hv 140.
- 중량%로, C: 0% 초과 0.02% 이하, N: 0% 초과 0.02% 이하, Si: 0.5% 이상 2.0% 이하, Mn: 0.1% 이상 0.3% 이하, Cr: 16.0% 이상 20.1% 이하, Mo: 1.0% 초과 2.0% 이하, Ti: 0.1% 이상 0.4% 이하, 잔부 Fe(철) 및 기타 불가피한 불순물을 포함하고,In weight %, C: more than 0% and 0.02% or less, N: more than 0% and 0.02% or less, Si: 0.5% or more and 2.0% or less, Mn: 0.1% or more and 0.3% or less, Cr: 16.0% or more and 20.1% or less, Mo : More than 1.0% and 2.0% or less, Ti: 0.1% or more and 0.4% or less, the balance including Fe (iron) and other unavoidable impurities,아래 식 (1)의 값이 130 이하이고, 아래 식 (2)의 값이 50 이하인, 슬라브를 제조하는 단계;Manufacturing a slab in which the value of Equation (1) below is 130 or less and the value of Equation (2) below is 50 or less;상기 슬라브를 재가열온도 1050 내지 1150℃에서 열간압연하여 열간압연재를 제조하는 단계;Preparing a hot-rolled material by hot-rolling the slab at a reheating temperature of 1050 to 1150 ° C;상기 열간압연재를 냉간압연하여 냉간압연재를 제조하는 단계; 및 Cold-rolling the hot-rolled material to produce a cold-rolled material; and상기 냉간압연재를 1050 내지 1150℃에서 최종 소둔하는 단계를 포함하는, 자기적 성질이 향상된 페라이트계 스테인리스강의 제조방법:Method for producing ferritic stainless steel with improved magnetic properties, comprising the step of final annealing the cold-rolled material at 1050 to 1150 ° C.:식 (1): 30 + 2500 * ([C] + [N]) - 15 * [Si] + 2.5 * [Cr] + 22 * [Mo]Equation (1): 30 + 2500 * ([C] + [N]) - 15 * [Si] + 2.5 * [Cr] + 22 * [Mo](식 (1)에서, [C], [N], [Si], [Cr], [Mo]는 각 원소의 함량(중량%)을 의미한다)(In formula (1), [C], [N], [Si], [Cr], and [Mo] mean the content (% by weight) of each element)식 (2): 18 + 800 * ([C] + [N]) - 6 * [Si] + [Cr] + 6 * [Mo]Equation (2): 18 + 800 * ([C] + [N]) - 6 * [Si] + [Cr] + 6 * [Mo](식 (2)에서, [C], [N], [Si], [Cr], [Mo]는 각 원소의 함량(중량%)을 의미한다).(In formula (2), [C], [N], [Si], [Cr], and [Mo] mean the content (% by weight) of each element).
- 청구항 9에 있어서,The method of claim 9,상기 냉간압연은 70% 이상의 압하율로 수행하는, 자기적 성질이 향상된 페라이트계 스테인리스강의 제조방법.The cold rolling is performed at a reduction ratio of 70% or more, a method for producing ferritic stainless steel with improved magnetic properties.
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EP22887478.0A EP4394075A1 (en) | 2021-10-26 | 2022-10-19 | Ferritic stainless steel having improved magnetic properties and manufacturing method therefor |
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KR1020210143705A KR20230059480A (en) | 2021-10-26 | 2021-10-26 | Ferritic stainless steel with improved magnetic properties and the method for manufacturing the same |
KR10-2021-0143705 | 2021-10-26 |
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EP (1) | EP4394075A1 (en) |
KR (1) | KR20230059480A (en) |
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WO (1) | WO2023075282A1 (en) |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH09176802A (en) * | 1995-12-27 | 1997-07-08 | Nippon Steel Corp | Ferritic stainless steel sheet excellent in magnetic property and its production |
KR20060049716A (en) * | 2004-07-01 | 2006-05-19 | 닛폰 스틸 앤드 스미킨 스테인레스 스틸 코포레이션 | A ferritic stainless steel wire and wire rod excellent in corrosion resistance, cold-rolling ability and toughness having reduced susrface defects and magnetic property |
CN101492792A (en) * | 2008-01-24 | 2009-07-29 | 宝山钢铁股份有限公司 | Free-machining ferritic stainless steel for ferromagnetic component |
JP2013185183A (en) * | 2012-03-07 | 2013-09-19 | Nippon Steel & Sumikin Stainless Steel Corp | Soft magnetic stainless steel fine wire and method for producing the same |
JP2020063472A (en) * | 2018-10-16 | 2020-04-23 | 日鉄ステンレス株式会社 | Ferritic stainless steel having excellent magnetic properties |
JP2021161469A (en) * | 2020-03-31 | 2021-10-11 | 日鉄ステンレス株式会社 | Ferritic stainless steel |
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2021
- 2021-10-26 KR KR1020210143705A patent/KR20230059480A/en unknown
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2022
- 2022-10-19 WO PCT/KR2022/015945 patent/WO2023075282A1/en active Application Filing
- 2022-10-19 EP EP22887478.0A patent/EP4394075A1/en active Pending
- 2022-10-19 CN CN202280071684.7A patent/CN118176314A/en active Pending
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH09176802A (en) * | 1995-12-27 | 1997-07-08 | Nippon Steel Corp | Ferritic stainless steel sheet excellent in magnetic property and its production |
KR20060049716A (en) * | 2004-07-01 | 2006-05-19 | 닛폰 스틸 앤드 스미킨 스테인레스 스틸 코포레이션 | A ferritic stainless steel wire and wire rod excellent in corrosion resistance, cold-rolling ability and toughness having reduced susrface defects and magnetic property |
CN101492792A (en) * | 2008-01-24 | 2009-07-29 | 宝山钢铁股份有限公司 | Free-machining ferritic stainless steel for ferromagnetic component |
JP2013185183A (en) * | 2012-03-07 | 2013-09-19 | Nippon Steel & Sumikin Stainless Steel Corp | Soft magnetic stainless steel fine wire and method for producing the same |
JP2020063472A (en) * | 2018-10-16 | 2020-04-23 | 日鉄ステンレス株式会社 | Ferritic stainless steel having excellent magnetic properties |
JP2021161469A (en) * | 2020-03-31 | 2021-10-11 | 日鉄ステンレス株式会社 | Ferritic stainless steel |
Also Published As
Publication number | Publication date |
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CN118176314A (en) | 2024-06-11 |
EP4394075A1 (en) | 2024-07-03 |
KR20230059480A (en) | 2023-05-03 |
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