EP4095279A1 - Platte aus martensitischem edelstahl und element aus martensitischem edelstahl - Google Patents

Platte aus martensitischem edelstahl und element aus martensitischem edelstahl Download PDF

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EP4095279A1
EP4095279A1 EP21744342.3A EP21744342A EP4095279A1 EP 4095279 A1 EP4095279 A1 EP 4095279A1 EP 21744342 A EP21744342 A EP 21744342A EP 4095279 A1 EP4095279 A1 EP 4095279A1
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steel sheet
stainless steel
martensitic stainless
δfe
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French (fr)
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EP4095279A4 (de
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Yoshiharu Inoue
Shinichi Tamura
Yoshihito Yamada
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Nippon Steel Stainless Steel Corp
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Nippon Steel Stainless Steel Corp
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    • C21D1/18—Hardening; Quenching with or without subsequent tempering
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
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    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
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    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
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    • 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
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    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
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    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
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    • 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
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    • C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
    • C21D9/0068—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for particular articles not mentioned below
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    • C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
    • C21D9/18—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for knives, scythes, scissors, or like hand cutting tools
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    • 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
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    • C22C38/001—Ferrous alloys, e.g. steel alloys containing N
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    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/002—Ferrous alloys, e.g. steel alloys containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60
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    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/008—Ferrous alloys, e.g. steel alloys containing tin
    • C—CHEMISTRY; METALLURGY
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    • 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
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    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
    • 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
    • C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/44—Ferrous alloys, e.g. steel alloys containing chromium with nickel 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
    • C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/46—Ferrous alloys, e.g. steel alloys containing chromium with nickel with vanadium
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
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    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/48—Ferrous alloys, e.g. steel alloys containing chromium with nickel with niobium or tantalum
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    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/50—Ferrous alloys, e.g. steel alloys containing chromium with nickel with titanium or zirconium
    • 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
    • C21D2211/008—Martensite

Definitions

  • the present invention relates to a martensitic stainless steel sheet and a martensitic stainless steel member that are excellent in corrosion resistance after being hardened. More specifically, the present invention relates to a martensitic stainless steel that exhibits excellent corrosion resistance even after being hardened by air cooling, which is used for manufacturing tableware knives, looms, tools, disk brakes, and the like.
  • Martensitic stainless steel (e.g. SUS420J1 steel and SUS420J2 steel) sheet is typically used for tools such as tableware knives (table knives), scissors, looms, caliper gauges, and the like.
  • tableware knives table knives
  • rust resistance is required for the material in itself. Further, it is also important for the material to have high hardness due to the need for wear resistance.
  • the manufacturing steps of tableware knives and the like typically include punching from a steel sheet, heating, hardening, and, subsequently, polishing.
  • the hardening step is often performed at a low cooling rate (e.g. air cooling) in view of the excellent hardenability of the martensitic stainless steel sheet.
  • Patent Literature 1 discloses a martensitic stainless steel excellent in corrosion resistance when being hardened by air cooling. In Patent Literature 1, approximately 0.06% of N is added as an element for improving corrosion resistance.
  • Patent Literature 2 discloses a steel added with a larger content of N than Patent Literature 1.
  • Patent Literature 3 discloses a steel whose N content is further increased using special equipment.
  • An object of the invention is to provide a martensitic stainless steel sheet and a martensitic stainless steel member that is excellent in end-surface corrosion resistance while retaining hardness sufficient for the use of martensitic stainless steel for tableware (e.g. table knives) and the like.
  • ⁇ Fe phase ⁇ ferrite phase
  • the cooling rate which greatly varies depending on hardening equipment, exceeds 100 degrees C/s in terms of average cooling rate from a hardening temperature to 600 degrees C (a temperature for the carbides to be almost completely precipitated) in water cooling during the hardening step, so that the carbide is restrained from being precipitated and the rust is unlikely to be generated.
  • the cooling rate by the air cooling typically used in the manufacturing steps of table knife is approximately 5 degrees C/s, so that the carbide precipitation cannot be restrained, thereby promoting rust generation.
  • the martensitic stainless steel sheet of the invention exhibits, while retaining hardness sufficient for the use of martensitic stainless steel for tableware (e.g. table knives), excellent corrosion resistance (especially, end-surface corrosion resistance). Accordingly, when the martensitic stainless steel sheet is used for a martensitic stainless steel member (e.g. tableware knives), increase in product lifetime can be expected in addition to improvement in corrosion resistance.
  • Fig. 1 shows a representative example of a cross section structure of a steel sheet of the invention, which is etched using modified Murakami reagent.
  • C which is an element that determines hardening hardness as with N, is required to be contained by 0.100% or more in order to achieve the hardness required for tableware knives.
  • the C content is 0.110% or more and 0.120% or more.
  • excessive addition of C increases hardening hardness more than necessary, resulting in increase in polishing load and decrease in toughness.
  • Cr carbide is likely to be precipitated to impair corrosion resistance at the time of hardening by air cooling. Accordingly, the C content is 0.170% or less.
  • the C content is 0.155% or less.
  • Si which is an element necessary for deoxidation during steelmaking process and effective for restraining oxide scales generated after hardening thermal treatment, is contained by 0.25% or more.
  • Si content is less than 0.25%, the oxide scales are excessively generated to increase final polishing load.
  • austenite is restrained from being generated to impair hardenability. Accordingly, the Si content is 0.60% or less.
  • Mn which is an austenite stabilizer element, is necessary for ensuring hardness at the time of hardening and the amount of martensite. Accordingly, the Mn content is 0.10% or more. However, Mn promotes generation of oxide scales at the time of hardening to increase subsequent polishing load. Accordingly, the Mn content is 0.60% or less. Further, excessive addition of Mn results in a large amount of MnS and consequent reduction in corrosion resistance.
  • P is an element contained in a form of impurities in a raw material that is hot metal or an alloy (e.g. ferrochrome).
  • P which is an element detrimental to toughness of a steel sheet after hot-rolled annealing and hardening, is contained by 0.035% or less. Excessive addition of P reduces hot workability and corrosion resistance.
  • S which has small solid solubility to an austenite phase, segregates in grain boundaries to promote reduction in hot workability. Further, excessive addition of S results in a large amount of MnS and consequent reduction in corrosion resistance. Accordingly, the S content is 0.015% or less.
  • Cr content is necessary to be at least 11.0% or more.
  • Cr has an effect of narrowing a range of austenite stability temperature. Accordingly, the Cr content is 15.0% or less.
  • the Cr content is 12.0% or more.
  • a preferable upper limit is 14.0% or less.
  • the Cr content is in a range from 12.0 to 14.0%.
  • Ni which is an austenite stabilizer element as in Mn, is necessary for ensuring hardness at the time of hardening and the amount of martensite. Further, Ni is effective for improving corrosion resistance. Accordingly, the Ni content is 0.05% or more. However, excessive addition of Ni may increase the stability of ⁇ phase to decrease the amount of martensite. Further, since Ni is expensive as compared with other elements, the upper limit of the Ni content is 0.60%.
  • Cu which is an austenite stabilizer element as in Mn and Ni, is also an element that improves corrosion resistance. Cu is also an element inevitably mixed into steel from scrap steel during the steelmaking process.
  • the Cu content is 0.006% or more.
  • the Cu content is 0.02% or more.
  • the Cu content is 0.05% or more.
  • the Cu content is 0.50% or less. Though being inexpensive as compared with Ni, Cu is a relatively expensive element and thus is preferably as low in content as possible.
  • V 0.010 to 0.10%
  • V is an element often inevitably mixed from alloy elements of ferrochrome and the like. It is difficult to reduce the amount of V and too much load is applied during the steelmaking process. Accordingly, the V content is 0.010% or more. However, an excessive content of V narrows a range of austenite formation temperature. Accordingly, the V content is 0.10% or less. Further, excessive addition of V results in VN to fix N, thereby unfavorably reducing hardness and/or corrosion resistance.
  • Al which is an element effective for deoxidation, generates soluble inclusions in a form of CaS during hot rolling to reduce corrosion resistance, when being excessively contained. Accordingly, the Al content is 0.05% or less. The Al content is preferably 0.001% or more. Al may not be contained.
  • N which is an element that determines hardening hardness as with C and improves corrosion resistance
  • the N content in the invention is 0.040% or more.
  • the N content is 0.045% or more.
  • N is an element that increases production cost in a secondary refining process (e.g. VOD).
  • the N content is preferably as low as possible, which is less than 0.060%.
  • the N content is 0.057% or less.
  • C and N The elements that determine the hardness of the martensite phase in the steel are C and N, a sum of which contributes to the hardness. According to studies of the inventors, the contribution of N to the hardness is half of the contribution of C. Accordingly, in order to obtain the hardness necessary for tableware knife, it is necessary that C + 1/2N is 0.130% or more. Preferably, C + 1/2N is 0.150% or more. In contrast, when C +1/2N is excessive, the hardening hardness is so large that toughness of a product and/or an intermediate material (e.g. cast steel) during the manufacturing steps is impaired. Accordingly, C +1/2N is 0.190% or less. Preferably, C +1/2N is 0.180% or less, also preferably 0.175% or less.
  • ⁇ p defined by the formula (1) is 120 or more.
  • the hardness can greatly vary depending on hardening conditions.
  • ⁇ Fe in the steel increases.
  • ⁇ p is optionally adjusted to be 130 or more, or 140 or more.
  • ⁇ p is optionally 170 or less, or 150 or less.
  • the steel composition of the invention includes the above components and the balance consisting of Fe and impurities.
  • the steel composition of the invention optionally includes, in place of a part of Fe, Mo, Nb, Ti, Sn, and Bi in order to improve rust resistance and corrosion resistance.
  • Mo which is an element for improving corrosion resistance, achieves its effect when being added by 0.01% or more.
  • Mo is an expensive element and clear effect cannot be achieved by adding excessive amount. Accordingly, the upper limit of the Mo content is 1.0%.
  • Ti is an element that forms a carbonitride to restrain sensitization and decrease in corrosion resistance that are caused by precipitation of chromium carbonitride in stainless steel.
  • the above effect is achieved at a content of 0.005%.
  • excessively added Ti destabilizes the martensite phase to reduce hardness. Accordingly, the upper limit of the Ti content is 0.050%.
  • Nb is an element that forms a carbonitride to restrain sensitization and decrease in corrosion resistance that are caused by precipitation of chromium carbonitride in stainless steel. The above effect is achieved at a content of 0.005%. However, excessively added Nb destabilizes the martensite phase to reduce hardness. Accordingly, the upper limit of the Nb content is 0.050%.
  • Sn which is an element effective for improving corrosion resistance after hardening, is preferably added by a content of 0.01% or more, and by a content of 0.05% or more as necessary.
  • the Sn content is preferably 0.10% or less.
  • Bi is an element that improves corrosion resistance. Though the mechanism is not clearly known, it is believed that added Bi, which is capable of reducing the size of MnS that is likely to be a start point of rust generation, decreases the probability for creating the rust generation start points. The above effect is achieved by addition of 0.01% or more. Adding Bi at a content exceeding 0.20% only saturates the effect. Accordingly, the upper limit of the Bi content is 0.20%.
  • ⁇ ferrite ( ⁇ Fe) present at a sheet-thickness central part of a steel sheet greatly affects an end-surface corrosion resistance of the steel sheet.
  • ⁇ phase matrix phase
  • grain boundaries between ⁇ Fe and a matrix phase ( ⁇ phase) become a precipitation site for Cr carbide during the cooling process, causing sensitization near the precipitated Cr carbide, thereby decreasing the end-surface corrosion resistance.
  • N improves the end-surface corrosion resistance because N restrains the precipitation of the Cr carbide.
  • the steel sheet of the invention is a steel sheet before being hardened. It would be favorable if ⁇ Fe present in the steel sheet before being hardened could be measured. However, since all of the phases around ⁇ Fe are ferrite phases, it is difficult to measure the ⁇ Fe. In contrast, the structure around the ⁇ Fe present in the steel sheet after being hardened/tempered is a martensite phase, which is relatively easily measured. Accordingly, the ⁇ Fe amount in the (before being hardened) steel sheet of the invention is evaluated after subjecting the steel sheet to hardening and tempering processes. The hardening was performed by heating to 1050 degrees C, holding the temperature for 30 minutes, and cooling the steel sheet by air cooling. The tempering was performed at 150 degrees C for 30 minutes.
  • the hardening temperature is excessively low and/or the hardening time is excessively short, the remaining ferrite phase cannot be unfavorably distinguished from the ⁇ Fe phase.
  • the hardening temperature is excessively high and/or the hardening time is excessively long, the ⁇ Fe phase is unfavorably transformed into a phase different from an initial phase.
  • the steel sheet is hardened by air cooling. A steel sheet is subjected to hardening and tempering under the above evaluation conditions. Then, a presence area ratio of a ⁇ Fe layer ( ⁇ Fe amount) in a sheet-thickness cross section of the steel sheet is evaluated.
  • the N content in the steel sheet and steel member of the invention is not at a sufficiently high level. Accordingly, it is necessary to further reduce ⁇ Fe as compared with a steel sheet with larger N content.
  • excellent end-surface corrosion resistance can be achieved when the ⁇ Fe amount is less than 0.1%.
  • the corrosion resistance is increased as the ⁇ Fe amount is reduced.
  • the reduction in the ⁇ Fe amount requires long thermal treatment as described below. Accordingly, the ⁇ Fe amount is 0.05% or more.
  • the ⁇ Fe amount is preferably in a range of 0.05% or more and less than 0.1%.
  • a typically employed method is used as the manufacturing method of the steel sheet of the invention. Specifically, a slab whose components are adjusted is obtained through melting and casting processes. Then, the slab is hot rolled, box-annealed, shot-blasted, and pickled to produce a steel product.
  • the slab is preheated in order to regulate the ⁇ Fe amount at a level of less than 0.1%. ⁇ Fe can thus be generated in a less amount as compared with typical instances, thus achieving excellent end-surface corrosion resistance.
  • the preheating is preferably performed under a temperature from 1100 to 1150 degrees C for a soaking time of more than 50 hours to 100 hours or less. When the heating temperature exceeds 1150 degrees C, two phases ( ⁇ + ⁇ ) become stable, where the ⁇ Fe amount is unfavorably rapidly increased. Further, a large amount of the rapidly increased ⁇ Fe remains in subsequent steps, which may be a factor for decreasing the hardness.
  • ⁇ Fe unfavorably does not decrease even after heating for a long time.
  • the ⁇ Fe amount is smaller than in an instance where the slab is heated at a temperature exceeding 1150 degrees C. Accordingly, the hardness can be retained depending on subsequent steps.
  • the soaking time is 50 hours or less, the ⁇ Fe amount is unfavorably excessive.
  • the production cost unfavorably increases.
  • the preheating is optionally performed by heating the slab before being hot-rolled, and directly followed by the hot-rolling.
  • the produced steel sheet is punched and the punched sheet is hardened, tempered, and polished to produce a steel member.
  • the punched steel sheet before being hardened is optionally forged for reshaping.
  • preferable conditions for hardening and tempering are as follows.
  • the hardening temperature is preferably in a range from 1000 to 1150 degrees C. When the hardening temperature is less than 1000 degrees C, there is a less austenite phase during a high-temperature period, so that the hardness after being hardened is unfavorably small. In contrast, when the hardening temperature exceeds 1150 degrees C, the ⁇ phase and stable austenite phase increase, so that the hardness also unfavorably decreases.
  • the holding time during the hardening step is preferably in a range from one minute to an hour.
  • the holding time is less than one minute, there is a less austenite phase during a high-temperature period, so that the hardness after being hardened is unfavorably reduced.
  • the holding time exceeds one hour, the stable austenite phase increases, so that the hardness also unfavorably decreases.
  • the cooling rate during the hardening step is preferably 1 degree/sec or more in terms of an average cooling rate from a hardening temperature to 600 degrees C. If the cooling rate is less than 1 degree/sec, the hardness unfavorably decreases.
  • the air cooling used in the hardening step can achieve the above favorable cooling rate.
  • the tempering temperature is preferably in a range from 100 degrees C to 250 degrees C.
  • the tempering temperature of less than 100 degrees C is insufficient for achieving the tempering effect.
  • the tempering temperature exceeds 250 degrees C, the hardness unfavorably excessively decreases.
  • the steel sheet of the invention is produced by subjecting the slab to hot rolling, box-annealing, shot-blasting, and pickling. Further, the produced steel sheet is punched and the punched sheet is hardened, tempered, and polished to produce the steel member of the invention.
  • the steel sheet of the invention is a steel sheet before being hardened, whose steel structure has a crystal structure mainly made of ferrite and the like.
  • the steel member of the invention which is produced by subjecting the processed steel sheet to hardening and tempering, has a steel structure mainly made of martensite.
  • steels of compositions shown in Tables 1 and 2 were melted to be casted into 250-mm thick slabs. Subsequently, these slabs were subjected to thermal treatment (preheating) at 1150 degrees C for 60 hours to set the ⁇ Fe amount within a predetermined range. It should be noted that A2 steel was subjected to two different preheating processes (1175 degrees C for 60 hours, and 950 degrees C for 60 hours) to produce A2' steel and A2" steel.
  • the slabs were heated to 1150 degrees C and were subjected to hot rolling to produce hot-rolled steel sheets having a 3 to 8 mm sheet-thickness.
  • the hot-rolled steel sheets were annealed (box annealing).
  • the maximum heating temperature was set in a temperature range from 800 degrees C to 900 degrees C.
  • the surfaces of the annealed steel sheets were shot-blasted to remove scales and were pickled.
  • evaluation samples were cut from the steel sheets. Then, after the samples were heated to and held at 1050 degrees C for 30 minutes (hardening and tempering), the samples were air-cooled and tempered at 150 degrees C for 30 minutes to produce steel members. Subsequently, the ⁇ Fe amount and hardness were measured and end-surface corrosion resistance was evaluated on each of the steel members. The results are shown in Table 3.
  • the ⁇ Fe amount was measured on an end surface of a sample that was mirror-polished and etched to expose structures thereon.
  • the etching liquid which may be aqua regia or the like for the purpose of exposing ⁇ Fe, is preferably the modified Murakami reagent disclosed in Non-Patent Literature 1 that can etch ⁇ Fe in deep brown. Accordingly, the modified Murakami reagent was used for evaluation.
  • Fig. 1 shows a typical example of etched surface.
  • the structure exposed by the modified Murakami reagent was inspected with a microscope and a picture of ⁇ Fe of a predetermined width (2 mm in Example 1) in a thickness direction was taken. The taken picture was analyzed to calculate an area of ⁇ Fe, based on which an area ratio ([ ⁇ Fe area (mm 2 )/(2 mm ⁇ total thickness (mm))] ⁇ 100(%)) was calculated to obtain the ⁇ Fe amount.
  • the value of the area ratio is necessary to be less than 0.1%. More preferably, the value is in a range of 0.05% or more and less than 0.1%. Samples with a ⁇ Fe area ratio ( ⁇ Fe amount) of less than 0.1 % were evaluated to be acceptable (A) and samples with a ⁇ Fe area ratio of 0.1 % or more were evaluated to be unacceptable (X).
  • the hardness was evaluated on a surface of the sample, which had been #80 polish-finished, in accordance with JIS Z 2245 using C scale Rockwell hardness tester.
  • the hardness of 50 or more was evaluated to be acceptable (A), and the hardness of less than 50 was evaluated to be unacceptable (X).
  • All of the samples prepared by applying the predetermined hardening and tempering on the steel sheet of the invention are found to be excellent not only in end-surface corrosion resistance but also in other properties. Thus, they are suitable for steel sheet for tableware knives. In contrast, steels of Comparative Examples are inferior in end-surface corrosion resistance and/or other properties. Thus, they are clearly not suitable for steel sheet for tableware knives.
  • a member cut from the produced steel sheet was hardened and tempered under the conditions shown in Table 4 to prepare a steel member.
  • the member was heated at a temperature ranging from 1050 to 1150 degrees C and was controlled to be cooled at a cooling rate shown in Table 4 from the hardening temperature to 600 degrees C. Further, the member was subjected to a tempering process at a temperature ranging from 150 to 250 degrees C for a period ranging from 1 to 2 hours to produce the steel member.
  • the A2' steel and A2" steel were prepared in the same manner.
  • steels of the invention which are excellent not only in the end-surface corrosion resistance but also in other properties, are suitable for the steel member for tableware knives.
  • steels of Comparative Examples which are inferior in end-surface corrosion resistance and/or other properties, are clearly not suitable for the steel member for tableware knives.
  • the invention allows efficient production of a martensitic stainless steel member and its material (martensitic stainless steel sheet) that are excellent in end-surface corrosion resistance after being hardened by air cooling and improvement in corrosion resistance of tableware knives manufactured using the steel member, which is very industrially effective.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Heat Treatment Of Sheet Steel (AREA)
  • Heat Treatment Of Steel (AREA)
EP21744342.3A 2020-01-22 2021-01-15 Platte aus martensitischem edelstahl und element aus martensitischem edelstahl Pending EP4095279A4 (de)

Applications Claiming Priority (2)

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JP2020008086A JP2023046414A (ja) 2020-01-22 2020-01-22 マルテンサイト系ステンレス鋼板およびマルテンサイト系ステンレス鋼部材
PCT/JP2021/001195 WO2021149601A1 (ja) 2020-01-22 2021-01-15 マルテンサイト系ステンレス鋼板およびマルテンサイト系ステンレス鋼部材

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JP3422865B2 (ja) * 1995-01-19 2003-06-30 新日本製鐵株式会社 高強度マルテンサイト系ステンレス鋼部材の製造方法
KR20050054058A (ko) 2003-12-03 2005-06-10 주식회사 포스코 핀홀결함이 없는 마르텐사이트계 스테인레스강
JP2005248263A (ja) 2004-03-04 2005-09-15 Daido Steel Co Ltd マルテンサイト系ステンレス鋼
JP4337712B2 (ja) * 2004-11-19 2009-09-30 住友金属工業株式会社 マルテンサイト系ステンレス鋼
JP5033584B2 (ja) * 2006-12-08 2012-09-26 新日鐵住金ステンレス株式会社 耐食性に優れるマルテンサイト系ステンレス鋼
JP5335502B2 (ja) * 2009-03-19 2013-11-06 新日鐵住金ステンレス株式会社 耐食性に優れたマルテンサイト系ステンレス鋼
JP5501795B2 (ja) * 2010-02-24 2014-05-28 新日鐵住金ステンレス株式会社 溶接部の耐食性に優れた低クロム含有ステンレス鋼
WO2012157680A1 (ja) * 2011-05-16 2012-11-22 新日鐵住金ステンレス株式会社 自転車のディスクブレーキロータ用マルテンサイト系ステンレス鋼板およびその製造方法
JP6520465B2 (ja) * 2015-06-26 2019-05-29 日本製鉄株式会社 マルテンサイト系ステンレス鋼管の製造方法
JP6786418B2 (ja) * 2016-03-17 2020-11-18 日鉄ステンレス株式会社 ブレーキディスク用マルテンサイト系ステンレス鋼、およびブレーキディスク
JP6095822B1 (ja) * 2016-03-23 2017-03-15 日新製鋼株式会社 マルテンサイト系ステンレス鋼板およびメタルガスケット製造法
KR102169859B1 (ko) * 2016-04-12 2020-10-26 제이에프이 스틸 가부시키가이샤 마텐자이트계 스테인리스 강판
JP6526765B2 (ja) * 2017-10-05 2019-06-05 日鉄ステンレス株式会社 焼き入れ性および耐食性に優れた自転車ディスクブレーキロータ用マルテンサイト系ステンレス冷延鋼板、鋼帯およびその製造方法
CN107760989B (zh) * 2017-10-11 2019-06-07 张家港中环海陆特锻股份有限公司 超超临界汽轮机用高压调节阀阀碟制造工艺
JP6537659B1 (ja) * 2018-03-28 2019-07-03 日鉄ステンレス株式会社 マルテンサイト系ステンレス熱延鋼板、当該鋼板を用いたディスクブレーキロータの製造方法

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WO2021149601A1 (ja) 2021-07-29
CN115003838B (zh) 2023-06-02
TW202134450A (zh) 2021-09-16
KR20220115621A (ko) 2022-08-17
JP2023046414A (ja) 2023-04-05
EP4095279A4 (de) 2024-08-21
CN115003838A (zh) 2022-09-02

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