WO2022153790A1 - Matériau en acier inoxydable à base de martensite et son procédé de production - Google Patents

Matériau en acier inoxydable à base de martensite et son procédé de production Download PDF

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WO2022153790A1
WO2022153790A1 PCT/JP2021/046879 JP2021046879W WO2022153790A1 WO 2022153790 A1 WO2022153790 A1 WO 2022153790A1 JP 2021046879 W JP2021046879 W JP 2021046879W WO 2022153790 A1 WO2022153790 A1 WO 2022153790A1
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stainless steel
steel material
martensitic stainless
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航 西村
詠一朗 石丸
耕一 坪井
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日鉄ステンレス株式会社
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Priority to KR1020237012634A priority Critical patent/KR20230069179A/ko
Priority to EP21919678.9A priority patent/EP4279618A1/fr
Priority to CN202180069502.8A priority patent/CN116323991A/zh
Priority to JP2022575161A priority patent/JPWO2022153790A1/ja
Priority to US18/246,620 priority patent/US20230357906A1/en
Publication of WO2022153790A1 publication Critical patent/WO2022153790A1/fr

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    • C21D2211/00—Microstructure comprising significant phases
    • C21D2211/008—Martensite

Definitions

  • the present invention relates to a martensitic stainless steel material and a method for producing the same.
  • Patent Document 2 in terms of mass%, C: 0.40 to 0.50%, Si: 0.05 to 0.60%, Mn: 0.5 to 1.5%, P: 0.035. % Or less, S: 0.010% or less, Cr: 11.0 to 15.5%, Ni: 0.01 to 0.30%, Cu: 0.01 to 0.30%, Mo: 0.01 to 0.30%, V: 0.01 to 0.10%, Al: 0.02% or less, Sn: 0.002 to 0.10%, N: 0.010 to 0.035%, Ca: 0.
  • a martensite-based stainless steel material for cutting tools has been proposed, characterized in that the inclusions of 10 ⁇ m or more are 0.2 pieces / cm 2 or less.
  • Patent Document 3 Cr: 13.0-14.0% by weight, Mo: 1.15 to 1.35% by weight, C: 0.35 to 0.55% by weight, Si: 0.20 to 0.20 to 0.50% by weight, Mn: 0.20 to 0.50% by weight, P: 0.025% by weight or less, S: 0.020% by weight or less, balance: Fe and a group having a composition consisting of unavoidable impurity elements.
  • a step of producing a material a step of subjecting the base material to at least one of a high-density dislocation introduction method and an ultra-quenching solidification method and then quenching to obtain a microstructure ferrite steel, and a cold rolling of the ferrite steel.
  • a martensitic stainless steel material having fine crystal grains which comprises a step of quenching, plastically processing into a predetermined shape as necessary, and then quenching to obtain a martensitic stainless steel material having fine crystal grains.
  • the manufacturing method of is proposed.
  • the martensitic stainless steel material described in Patent Document 2 has insufficient workability or irregular patterns because the average particle size of inclusions (particularly carbides) is not controlled. There is. Further, the martensitic stainless steel material described in Patent Document 3 is not suitable for mass production because it has introduced a special process such as a high-density dislocation introduction method or an ultra-quenching solidification method. In addition, this martensitic stainless steel material has a high Mo content and is costly. In the conventional martensitic stainless steel material in which the C content is reduced in this way, the above-mentioned problems have occurred.
  • the present invention has been made to solve the above problems, and has good workability, high hardness and corrosion resistance after quenching or quenching and tempering, and martensitic capable of suppressing the occurrence of irregular patterns.
  • An object of the present invention is to provide a martensitic stainless steel material and a method for producing the same.
  • C 0.30 to 0.60%, Si: 0.05 to 1.00%, Mn: 0.05 to 1.50%, P: 0.040% or less on a mass basis.
  • the average particle size of the carbide is 0.50 ⁇ m or less, A martensitic stainless steel material having 0.20 pieces / cm 2 or less of the carbide having a size of 10 ⁇ m or more.
  • C 0.30 to 0.60%, Si: 0.05 to 1.00%, Mn: 0.05 to 1.50%, P: 0.040% or less on a mass basis.
  • a slab having a composition composed of impurities according to the formula (1): T [° C.] 6500 / (4-log C [%])-273 ... (1)
  • This is a method for producing a martensitic stainless steel material which comprises a hot rolling step of performing hot rolling after performing heat treatment at a temperature of T or higher represented by (2) for 1 to 5 hours.
  • the present invention it is possible to provide a martensitic stainless steel material having good workability, high hardness and corrosion resistance after quenching or quenching and tempering, and capable of suppressing the occurrence of irregular patterns, and a method for producing the same.
  • the martensite-based stainless steel material according to the embodiment of the present invention has C: 0.30 to 0.60%, Si: 0.05 to 1.00%, Mn: 0.05 to 1.50%, P: 0. .040% or less, S: 0.030% or less, Cr: 13.0-18.0%, Ni: 0.01 to 0.30%, Mo: 0.01 to 1.00%, Al: 0. 030% or less, N: 0.010 to 0.350%, Ca: 0.0001 to 0.0030%, O: 0.001 to 0.010%, and 2.5C + N is 1.10% or more.
  • the balance is composed of Fe and impurities.
  • the "steel material” means a material having various material shapes such as a steel plate.
  • the “steel plate” is a concept including a steel strip.
  • the “impurity” is a component mixed by various factors of raw materials such as ore and scrap, and various factors in the manufacturing process when the stainless steel material is industrially manufactured, and is allowed as long as it does not adversely affect the present invention. Means what is done. Examples of impurities include Zn, Pb, Se, Sb, H, Ga, Ta, Mg, Zr and the like.
  • the martensite-based stainless steel material according to the embodiment of the present invention has V: 0.50% or less, Nb: 0.30% or less, Ti: 0.3% or less, Cu: 4.0% or less, Sn: One or more of 0.100% or less, B: 0.0050% or less, and Co: 0.30% or less can be further contained.
  • V 0.50% or less
  • Nb 0.30% or less
  • Ti 0.3% or less
  • Cu 4.0% or less
  • Sn One or more of 0.100% or less
  • B 0.0050% or less
  • Co 0.30% or less
  • C is an essential element for obtaining a predetermined hardness (Vickers hardness) after quenching or quenching and tempering.
  • Vickers hardness a hardness of 500 HV or more
  • the C content needs to be 0.30% or more. If C is added excessively, sensitization during quenching is promoted and corrosion resistance is impaired, and the toughness after quenching or tempering is also lowered due to the unsolid solution carbonitride. Therefore, the C content is set to 0.60% or less. There is a need to.
  • the lower limit of the C content is preferably 0.32%, and the upper limit is preferably 0.58%.
  • Si 0.05 to 1.00%>
  • Si is an element that is necessary for deoxidation during dissolution refining and is also useful for suppressing the formation of oxidative scale during quenching. Further, if the Si content is low, deoxidation tends to be insufficient, carbides increase, and rusting may occur starting from this, resulting in a decrease in corrosion resistance. Therefore, the Si content needs to be 0.05% or more. On the other hand, Si narrows the austenite single-phase temperature range and impairs quenching stability, so the Si content needs to be 1.00% or less. From the viewpoint of stably obtaining the above-mentioned effect of Si, the lower limit value of the Si content is preferably 0.07%, and the upper limit value is preferably 0.98%.
  • Mn is an element added as a deoxidizer and contributes to the improvement of hardenability by expanding the austenite single-phase region. If Mn is not sufficiently added, the two-phase region expands and the ⁇ phase increases. As a result, the amount of Cr carbonitride increases, and a Cr-deficient layer is formed around the Cr carbonitride, which tends to be a starting point of rust and lowers corrosion resistance. Therefore, it is necessary to set the Mn content to 0.05% or more. From the viewpoint of stably obtaining the above effect of Mn, the lower limit of the Mn content is preferably 0.07%.
  • Mn content 1.50% or less. Considering the decrease in corrosion resistance due to granules such as MnS, 1.45% or less is preferable.
  • P is an element contained as an impurity in the main raw materials such as hot metal and ferrochrome which are raw materials. It is an element harmful to the toughness and corrosion resistance of hot-rolled annealed plates and materials after quenching. Therefore, the P content needs to be 0.040% or less, preferably 0.038% or less.
  • the lower limit of the P content is not particularly limited, but excessive reduction causes problems such as making the use of high-purity raw materials indispensable, which leads to an increase in cost. Therefore, the lower limit of the P content is set. 0.010% is preferable.
  • the lower limit of the S content is not particularly limited, but the smaller the S content, the better the corrosion resistance, while the desulfurization load increases and the manufacturing cost increases. Therefore, the lower limit of the S content is preferably 0.001%.
  • Cr is an element for maintaining the corrosion resistance required in the main use of martensitic stainless steel materials. Therefore, it is necessary to set the Cr content to 13.0% or more. On the other hand, from the viewpoint of suppressing the formation of retained austenite after quenching, the Cr content needs to be 18.0% or less. From the viewpoint of stably obtaining the above-mentioned effect of Cr, the lower limit value of the Cr content is preferably 13.1%, and the upper limit value is preferably 17.8%.
  • Ni is an austenite stabilizing element and also has the effect of improving toughness after quenching or quenching and tempering.
  • the press formability may be deteriorated due to solid solution strengthening in the hot-rolled annealed plate, and the production cost is increased because it is an expensive element. Therefore, the Ni content needs to be 0.30% or less.
  • Ni is an element effective in suppressing the progress of pitting corrosion. From the viewpoint of stably obtaining the above-mentioned effect of Ni, the lower limit value of the Ni content is preferably 0.02%, and the upper limit value is preferably 0.27%.
  • Mo is an element effective for improving the corrosion resistance of a martensite structure containing ⁇ ferrite. From the viewpoint of obtaining this effect, the Mo content needs to be 0.01% or more. On the other hand, Mo is a stabilizing element of the ferrite phase, and excessive addition impairs the quenching characteristics by narrowing the austenite single-phase temperature range. Therefore, the Mo content needs to be 1.00% or less. From the viewpoint of stably obtaining the above-mentioned effect of Mo, the lower limit value of the Mo content is preferably 0.02%, the upper limit value is preferably 0.50%, and more preferably 0.30%. ..
  • Al is an element that is added as a deoxidizing element and also improves oxidation resistance. However, if a large amount of Al is contained, carbides tend to become large. Therefore, the Al content needs to be 0.030% or less, preferably 0.025% or less, and more preferably 0.020% or less.
  • the lower limit of the Al content is not particularly limited and may not contain Al. However, from the viewpoint of obtaining the above effect by Al, the lower limit value of Al is preferably 0.001%.
  • Al is T.I. Al.
  • N is an element essential for obtaining a predetermined hardness (Vickers hardness) after quenching or quenching and tempering.
  • Vickers hardness a predetermined hardness
  • N since the content of C is reduced, it is necessary to contain N instead.
  • N also has the effect of improving corrosion resistance when it is dissolved in solid solution. From the viewpoint of obtaining these effects, the N content needs to be 0.010% or more.
  • N may form a Cr nitride to form a Cr-deficient layer, in which case the corrosion resistance is reduced. Further, if N is added excessively, it is difficult to control at the steelmaking stage, and bubble-based defects are likely to be formed.
  • the content of N needs to be 0.350% or less.
  • the lower limit of the content of N is preferably 0.020%, more preferably 0.025%, still more preferably 0.036%, and the upper limit is It is preferably 0.300%, more preferably 0.290%.
  • Ca 0.0001 to 0.0030%>
  • Ca is added to adjust the composition at the steelmaking stage, but it acts as a strong deoxidizing material and has the effect of promoting deoxidation.
  • Ca is a strong deoxidizing element, most of it floats in molten steel as inclusions and hardly remains in steel.
  • the Ca content needs to be 0.0030% or less, preferably 0.0010% or less.
  • the Ca content is set to 0.0001% or more.
  • O is an important element together with Al and Ca.
  • the content of O needs to be 0.010% or less.
  • the content of O is set to 0.001% or more. From the viewpoint of the balance between cost and corrosion resistance, the lower limit of the O content is preferably 0.002%, and the upper limit is 0.009%.
  • ⁇ 2.5C + N is 1.10% or more>
  • C and N are essential elements for obtaining a predetermined hardness (Vickers hardness) after quenching or quenching and tempering.
  • N is contained instead of reducing the content of C, and C contributes 2.5 times as much as N to the hardness. Therefore, from the viewpoint of obtaining a predetermined hardness, 2.5C + N needs to be 1.10% or more, preferably 1.25% or more.
  • the upper limit of 2.5C + N is not particularly limited, but is preferably 1.80%, more preferably 1.70%, and even more preferably 1.60%.
  • V is an element that forms fine carbonitrides and contributes to the improvement of corrosion resistance, and is added as necessary. However, if V is added in excess, the precipitate may be coarsened, and as a result, the toughness after quenching is lowered. Therefore, the V content is 0.50% or less, preferably 0.30% or less, and more preferably 0.20% or less.
  • the lower limit of the V content is not particularly limited, but V may be mixed in the alloy raw material as an unavoidable impurity, and it may be difficult to remove it in the refining step. From the viewpoint of obtaining the above effects, the lower limit of the V content is preferably 0.01%, more preferably 0.02%, and even more preferably 0.03%.
  • Nb is an element that forms a carbonitride and suppresses sensitization and deterioration of corrosion resistance due to precipitation of Cr carbonitride, and is added as necessary. However, excessive addition of Nb destabilizes the martensite phase and reduces hardness. Therefore, the content of Nb is 0.30% or less, preferably 0.28% or less, and more preferably 0.25% or less.
  • the lower limit of the Nb content is not particularly limited, but is preferably 0.01%, more preferably 0.05% from the viewpoint of obtaining the above effects.
  • Ti is an element that forms a carbonitride and suppresses sensitization and deterioration of corrosion resistance due to precipitation of Cr carbonitride, and is added as necessary. However, when Ti is added in excess, coarse TiN is formed, which leads to the occurrence of thermal rolling and a decrease in toughness. Therefore, the Ti content is 0.3% or less, preferably 0.25% or less.
  • the lower limit of the Ti content is not particularly limited, but is preferably 0.01%, more preferably 0.06%, and even more preferably 0.10% from the viewpoint of obtaining the above effects.
  • Cu is an element that is effective in improving the corrosion resistance of the martensite structure containing ⁇ ferrite and also contributes to the improvement of hardenability as an austenite stabilizing element, and is added as necessary.
  • the Cu content is 4.0% or less, preferably 3.8% or less, and more preferably 3.5% or less.
  • the lower limit of the Cu content is not particularly limited, but is preferably 1.0%, more preferably 1.3%, and even more preferably 1.5% from the viewpoint of obtaining the above effects.
  • Sn is an element effective for improving corrosion resistance after quenching or quenching and tempering, and is added as necessary. However, excessive addition of Sn promotes ear cracking during hot spreading. Therefore, the Sn content is 0.100% or less, preferably 0.090% or less.
  • the lower limit of the Sn content is not particularly limited, but is preferably 0.002%, preferably 0.050% from the viewpoint of obtaining the above effects.
  • B is an element effective for improving hot workability, and is added as needed. However, excessive addition of B may reduce hardenability due to composite precipitation of boride and carbide. Therefore, the content of B is 0.0050% or less, preferably 0.0045% or less.
  • the lower limit of the B content is not particularly limited, but is preferably 0.0002% from the viewpoint of obtaining the above effects.
  • Co is an element that improves heat resistance and is added as needed. However, since Co is expensive, if the content of Co is too large, the manufacturing cost will increase. Therefore, the Co content is 0.30% or less, preferably 0.10% or less, and more preferably 0.05% or less.
  • the lower limit of the Co content is not particularly limited, but is preferably 0.01% from the viewpoint of obtaining the above effects.
  • the martensitic stainless steel material according to the embodiment of the present invention has an average particle size of carbides of 0.50 ⁇ m or less, preferably 0.48 ⁇ m or less.
  • the lower limit of the average particle size of the carbide is not particularly limited, but is preferably 0.01 ⁇ m, more preferably 0.05 ⁇ m, and further preferably 0.10 ⁇ m.
  • the carbides that specify the average particle size are both eutectic carbides produced during casting and precipitated carbides produced during the rolling process.
  • the average particle size of the carbides can be calculated by observing the cross section of the martensitic stainless steel material by SEM, measuring the equivalent circle diameter of each carbide in the observation field, and obtaining the average value thereof.
  • the martensitic stainless steel material according to the embodiment of the present invention contains 0.20 pieces / cm 2 or less, preferably 0.19 pieces / cm 2 or less of carbides having a size of 10 ⁇ m or more. Since carbides having a size of 10 ⁇ m or more are likely to be a starting point of rust, rusting can be suppressed and corrosion resistance can be improved by controlling the number of carbides having a size of 10 ⁇ m or more in such a range. The smaller the amount of carbide having a size of 10 ⁇ m or more, the better, and thus the amount is not particularly limited, but is generally 0.01 pieces / cm 2 or more.
  • the carbides having a size of 10 ⁇ m or more are mainly eutectic carbides produced during casting.
  • the size of the carbide refers to (major axis + minor axis) / 2 of the carbide.
  • the number of carbides having a size of 10 ⁇ m or more is calculated by observing the cross section of the martensite-based stainless steel material with an optical microscope to determine the number of carbides having a size of 10 ⁇ m or more and dividing the number by the area of the measurement region. be able to.
  • the martensitic stainless steel material according to the embodiment of the present invention has a hardness (Vickers hardness) of 500 HV or more after quenching or quenching and tempering.
  • the hardness is preferably 550 HV or more.
  • the upper limit of the hardness is not particularly limited, but is preferably 900 HV, more preferably 800 HV.
  • quenching is performed at 1000 to 1100 ° C. Tempering is carried out at 100-400 ° C. After quenching, it is desirable to perform subzero treatment at ⁇ 200 to ⁇ 50 ° C.
  • the hardness means a value measured at room temperature (25 ° C.) using a Vickers hardness tester.
  • the martensitic stainless steel material according to the embodiment of the present invention is not particularly limited, but is preferably a hot-rolled plate, a hot-rolled annealed plate, a cold-rolled plate, or a cold-rolled annealed plate.
  • the martensitic stainless steel material according to the embodiment of the present invention is obtained after heat-treating a slab having the same composition as the above-mentioned martensitic stainless steel material at a temperature of T or higher represented by the formula (1) for 1 to 5 hours.
  • T [° C.] 6500 / (4-log C [%])-273 ... (1)
  • the eutectic carbides produced during casting can be completely dissolved, so that the average particle size of the carbides and the number of carbides having a size of 10 ⁇ m or more are controlled within the above ranges. It becomes possible.
  • the conditions for hot rolling are not particularly limited, but it is preferable to finish the sheet thickness to 2 to 8 mm by rough rolling and finish rolling.
  • the hot rolled plate is wound at a winding temperature of 800 ° C to 900 ° C.
  • the wound hot-rolled plate is coiled.
  • a softening step is performed in which the coiled hot-rolled plate is annealed at a temperature of Ac1 to (Ac1 to -50 ° C.) for 1 to 5 hours.
  • a hot-rolled annealed plate can be obtained.
  • coarsening of carbides is suppressed, so that the average particle size of carbides and the number of carbides having a size of 10 ⁇ m or more can be stably controlled within the above range. It becomes.
  • Annealing is carried out by holding the heated coiled hot-rolled plate at a temperature of Ac1 point to (Ac1 point-50 ° C.).
  • annealing is not performed by cooling the coiled hot-rolled plate once and then reheating it to the temperature. Annealing is performed in a batch annealing furnace.
  • the Ac1 point is calculated by the following equation (2).
  • Ac1 -250C + 73Si-66Mn-115Ni + 35Cr + 60Mo-18Cu + 620Ti + 750Al-280N + 410 ...
  • each element symbol is the mass% of each element.
  • the hot-rolled annealed plate obtained in the softening step may be pickled if necessary.
  • a cold rolling step of cold rolling is performed on the hot-rolled annealed sheet that has been pickled as needed.
  • a cold rolled plate can be obtained by performing a cold rolling step.
  • the conditions for cold rolling are not particularly limited and may be appropriately adjusted according to the required cold rolled sheet.
  • the cold rolled sheet is annealed by heating at a heating rate of 50 ° C./sec or more, preferably 100 ° C./sec or more in a temperature range from 100 ° C. to Ac1 point to (Ac1 point-50 ° C.).
  • the process is carried out.
  • Annealing can be started from a state in which the cold rolled plate is in a temperature range of room temperature (25 ° C.) or higher and lower than 100 ° C. By performing this annealing step, a cold-rolled annealed plate can be obtained.
  • the number of carbides having a size of 10 ⁇ m or more and the average particle size of the carbides are controlled within a predetermined range. Therefore, the workability is good, and the hardness and corrosion resistance are high after quenching or quenching and tempering, and the occurrence of irregular patterns can be suppressed.
  • the steel with the steel composition shown in Table 1 was melted and cast into a slab with a thickness of 200 mm. After heat-treating this slab at the temperature and time shown in Table 2, hot rolling (rough rolling and finish rolling) was performed to obtain a hot-rolled plate with a plate thickness of 3 mm, which was wound into a coil at a winding temperature of 850 ° C. I took it. Next, this coiled hot-rolled plate was transferred to a batch annealing furnace, and a softening step was performed at the temperature and time shown in Table 2. Next, the hot-rolled annealed sheet obtained in the softening step is cold-rolled, and then the cold-rolled sheet is annealed by heating at the heating rate shown in Table 2 in the temperature range from 100 ° C.
  • the process was performed. Annealing was started from a state where the cold rolled plate was at room temperature (25 ° C.). Then, pickling was performed. The obtained cold-rolled annealed sheet (martensitic stainless steel material) was evaluated as follows.
  • the obtained cold-spread annealed plate was heated to 1000 to 1100 ° C. and quenched, and then the surface was surface-polished with # 80, and the JIS surface hardness (quenched hardness) was measured with a Vickers hardness tester.
  • the measurement temperature was room temperature (25 ° C.).
  • the hardness was 500 HV or higher.
  • the cross section parallel to the rolling direction and the plate thickness direction of the obtained cold-rolled annealed plate is observed by SEM, and among the carbides observed in the observation field, the carbide particles having a circle-equivalent diameter of less than 0.10 ⁇ m and the observation field.
  • the circle-equivalent diameter ( ⁇ m) is measured for all the charcoal particles except the charcoal particles in which a part of the particles protrudes from the measurement target, and the sum of the circle-equivalent diameters of the charcoal particles to be measured is measured.
  • the value divided by the total number was taken as the average diameter of the charcoal ( ⁇ m). However, the total number of carbide particles to be measured was set to 100 or more by a plurality of non-overlapping observation fields selected at random.
  • the circle-equivalent diameter of the carbide particles was calculated from the area of the carbide particles obtained by image processing the SEM image with image processing software.
  • the obtained cold-rolled annealed plate was punched into a blade shape to collect a steel material, which was heated at 1000 to 1100 ° C. for quenching. Next, the surface of the steel material was polished, and one end surface in the longitudinal direction was wet-polished to perform blade cutting to obtain a test material (blade). Those without blade chipping during this blade attachment process were evaluated as acceptable ( ⁇ ), and those with blade chipping were evaluated as rejected (x).
  • the cold-rolled annealed plates (martensite-based stainless steel materials) of Examples 1 to 23 had good hardness and corrosion resistance after quenching. Further, since these cold-rolled annealed plates have a small average particle size of carbides and a small number of carbides having a size of 10 ⁇ m or more, no blade chipping occurs during blade cutting, and the workability is good, and the surface of the blade is good. The occurrence of irregular patterns was also suppressed.
  • FIG. 1 shows a graph showing the relationship between 2.5C + N and hardness in the above Examples and Comparative Examples. As shown in FIG. 1, it was found that there is a proportional relationship between 2.5C + N and hardness, and that increasing 2.5C + N tends to increase hardness as well. In particular, it was found that the hardness can be made 500 HV or more by controlling 2.5 C + N to 1.10% or more.
  • a martensitic stainless steel material having good workability, high hardness and corrosion resistance after quenching or quenching and tempering, and capable of suppressing the occurrence of irregular patterns, and production thereof.
  • a method can be provided.

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Abstract

Ce matériau d'acier inoxydable à base de martensite a une composition qui comprend, en masse, 0,30 à 0,60 % de C, 0,05 à 1,00 % de Si, 0,05 à 1,50 % de Mn, 0,040 % ou moins de P, 0,030 % ou moins de S, 13,0 à 18,0 % de Cr, 0,01 à 0,30 % de Ni, 0,01 à 1,00 % de Mo, 0,030 % ou moins d'Al, 0,010 à 0,350 % de N, 0,0001 à 0,0030 % de Ca, et 0,001 à 0,010 % de O, et dans laquelle 2,5 C + N est égal ou supérieur à 1,10 %, la partie restante étant du Fe et des impuretés. Dans ce matériau d'acier inoxydable à base de martensite, le diamètre moyen des particules de carbures est de 0,50 µm ou moins. En outre, des carbures ayant une taille égale ou supérieure à 10 µm sont inclus dans une quantité inférieure ou égale à 0,20 particules/cm2.
PCT/JP2021/046879 2021-01-13 2021-12-17 Matériau en acier inoxydable à base de martensite et son procédé de production WO2022153790A1 (fr)

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EP21919678.9A EP4279618A1 (fr) 2021-01-13 2021-12-17 Matériau en acier inoxydable à base de martensite et son procédé de production
CN202180069502.8A CN116323991A (zh) 2021-01-13 2021-12-17 马氏体系不锈钢钢材及其制造方法
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WO2024085736A1 (fr) * 2022-10-21 2024-04-25 주식회사 포스코 Acier inoxydable martensitique et son procédé de fabrication

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US20020162614A1 (en) * 2001-02-14 2002-11-07 Bohler Edelstahl Gmbh Steel for plastic molds and process for their heat treatment
JP2003313612A (ja) 2002-04-23 2003-11-06 Matsushita Electric Works Ltd 結晶粒微細化マルテンサイト系ステンレス鋼の製造方法、および同ステンレス鋼を用いた刃物
JP2018009231A (ja) 2016-07-15 2018-01-18 新日鐵住金ステンレス株式会社 製造性と耐食性に優れた刃物用マルテンサイト系ステンレス鋼板
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WO2021124511A1 (fr) * 2019-12-19 2021-06-24 日鉄ステンレス株式会社 Acier martensitique à haute dureté et à haute résistance à la corrosion ayant une excellente aptitude au façonnage à froid et son procédé de production

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JP2000273587A (ja) 1999-03-23 2000-10-03 Aichi Steel Works Ltd 耐食性と切れ味持続性および加工性に優れた刃物用ステンレス鋼
US20020162614A1 (en) * 2001-02-14 2002-11-07 Bohler Edelstahl Gmbh Steel for plastic molds and process for their heat treatment
JP2003313612A (ja) 2002-04-23 2003-11-06 Matsushita Electric Works Ltd 結晶粒微細化マルテンサイト系ステンレス鋼の製造方法、および同ステンレス鋼を用いた刃物
JP2018009231A (ja) 2016-07-15 2018-01-18 新日鐵住金ステンレス株式会社 製造性と耐食性に優れた刃物用マルテンサイト系ステンレス鋼板
JP2019014916A (ja) * 2017-07-03 2019-01-31 株式会社不二越 マルテンサイト系ステンレス鋼
JP2020094275A (ja) * 2018-12-04 2020-06-18 日立金属株式会社 マルテンサイト系ステンレス鋼部品およびその製造方法
WO2021124511A1 (fr) * 2019-12-19 2021-06-24 日鉄ステンレス株式会社 Acier martensitique à haute dureté et à haute résistance à la corrosion ayant une excellente aptitude au façonnage à froid et son procédé de production

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Publication number Priority date Publication date Assignee Title
WO2024085736A1 (fr) * 2022-10-21 2024-04-25 주식회사 포스코 Acier inoxydable martensitique et son procédé de fabrication

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