US20200370154A1 - Non-magnetic austenitic stainless steel having improved strength and surface conductivity - Google Patents

Non-magnetic austenitic stainless steel having improved strength and surface conductivity Download PDF

Info

Publication number
US20200370154A1
US20200370154A1 US16/770,244 US201816770244A US2020370154A1 US 20200370154 A1 US20200370154 A1 US 20200370154A1 US 201816770244 A US201816770244 A US 201816770244A US 2020370154 A1 US2020370154 A1 US 2020370154A1
Authority
US
United States
Prior art keywords
stainless steel
austenitic stainless
content
less
present disclosure
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
US16/770,244
Other languages
English (en)
Inventor
Jong-Hee Kim
Kwang Min Kim
Bo-Sung Seo
Hak Kim
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Posco Holdings Inc
Original Assignee
Posco Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Posco Co Ltd filed Critical Posco Co Ltd
Assigned to POSCO reassignment POSCO ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: KIM, HAK, KIM, JONG-HEE, KIM, KWANG MIN, SEO, BO-SUNG
Publication of US20200370154A1 publication Critical patent/US20200370154A1/en
Assigned to POSCO HOLDINGS INC. reassignment POSCO HOLDINGS INC. CHANGE OF NAME (SEE DOCUMENT FOR DETAILS). Assignors: POSCO
Assigned to POSCO CO., LTD reassignment POSCO CO., LTD ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: POSCO HOLDINGS INC.
Pending legal-status Critical Current

Links

Images

Classifications

    • 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
    • C22C38/38—Ferrous alloys, e.g. steel alloys containing chromium with more than 1.5% by weight of manganese
    • 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
    • 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
    • C21D6/00—Heat treatment of ferrous alloys
    • C21D6/005—Heat treatment of ferrous alloys containing Mn
    • 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
    • C21D7/00—Modifying the physical properties of iron or steel by deformation
    • C21D7/02—Modifying the physical properties of iron or steel by deformation by cold working
    • 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
    • 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
    • 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
    • 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
    • C22C38/002—Ferrous alloys, e.g. steel alloys containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60
    • 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
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/20—Ferrous alloys, e.g. steel alloys containing chromium with copper
    • 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
    • C21D2211/001—Austenite
    • 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

Definitions

  • the present disclosure relates to a non-magnetic austenitic stainless steel, and more particularly, to a non-magnetic austenitic stainless steel with improved strength and surface conductivity applicable to environments requiring strength and surface conductivity along with non-magnetic properties.
  • materials for electronic parts require austenitic stainless steel having excellent surface conductivity in addition to high strength and non-magnetic characteristics or high strength and non-magnetic characteristics.
  • a material for electronic parts contains a large amount of expensive Ni, which has a problem of increasing the raw material cost.
  • Austenitic stainless steel represented by STS304
  • STS304 has good corrosion resistance, and exhibits a non-magnetic austenite structure in annealing heat treatment, and is used as a non-magnetic steel in various devices.
  • working is performed depending on the application, and when deep drawing and press working are applied to STS304 steel, due to the phase transformation to strain induced martensite structure, it is difficult to maintain non-magnetic properties, and there is a problem that delayed cracks occur.
  • the embodiments of the present disclosure solve the above problems and provide non-magnetic austenitic stainless steel with improved strength and surface conductivity by controlling the content element without adding Ni to suppress strain induced martensite, and controlling ⁇ -ferrite content during solidification.
  • an austenitic stainless steel includes, in percent (%) by weight of the entire composition, C: 0.07 to 0.2%, N: 0.15 to 0.4%, Si: 0.8 to 2%, Mn: 16 to 22%, S: 0.01% or less (excluding 0), Cr: 12.5 to 20%, Cu: 1 to 3%, the remainder of iron (Fe) and other inevitable impurities, and satisfies the following equation (1).
  • Ni, Cr, Mn, Si, C, N are % by weight of each element.
  • the yield strength represented by the following equation (2) may be 450 MPa or more.
  • C, N, Cu, Mn are % by weight of each element.
  • the ferrite content measured after 70% cold working may be less than 0.1%.
  • the permeability may be 1.005 or less even at 70% cold working
  • the stacking fault energy (SFE) represented by the following equation (3) may be 41 mJ/m 2 or more.
  • Ni, Cu, Cr, N, Si, Mn are % by weight of each element.
  • the cold rolled material hardness (Hv) value may be 215 or more.
  • the Cu+Mn content in the region within 2 nm of the passivation film may be 0.2% or more.
  • the surface resistance may be less than 10 m ⁇ cm 2 .
  • non-magnetic austenitic stainless steel with improved strength and surface conductivity can be used in various applications for non-magnetic components used in various devices.
  • an additional process of heat-treating the material for a long time in order to remove magnetism by ⁇ -ferrite is unnecessary, and thus it is possible to provide a non-magnetic austenitic stainless steel with a simple manufacturing process.
  • FIG. 1 is a graph showing the correlation between Ni equivalent and permeability.
  • FIG. 2 is a graph showing the correlation between the Ni equivalent and the yield strength prediction equation.
  • a non-magnetic austenitic stainless steel with improved strength and surface conductivity includes, in percent (%) by weight of the entire composition, C: 0.07 to 0.2%, N: 0.15 to 0.4%, Si: 0.8 to 2%, Mn: 16 to 22%, S: 0.01% or less (excluding 0), Cr: 12.5 to 20%, Cu: 1 to 3%, the remainder of iron (Fe) and other inevitable impurities, and satisfies the following equation (1).
  • Ni, Cr, Mn, Si, C, N are % by weight of each element.
  • part when a part “includes” or “comprises” an element, unless there is a particular description contrary thereto, the part may further include other elements, not excluding the other elements.
  • non-magnetic austenitic stainless steel which can secure non-magnetic properties even if it is manufactured in a normal process without requiring an additional process for decomposing ⁇ -ferrite by controlling the content of ⁇ -ferrite present in the microstructure of the steel and has improved strength and surface conductivity compared to commonly used STS304 stainless steel.
  • the present disclosure provides austenitic stainless steel that exhibits excellent non-magnetic properties only by controlling the alloying element, without the addition of expensive Ni, even without an additional heat treatment process.
  • An austenitic stainless steel includes, in percent (%) by weight of the entire composition, C: 0.07 to 0.2%, N: 0.15 to 0.4%, Si: 0.8 to 2%, Mn: 16 to 22%, S: 0.01% or less (excluding 0), Cr: 12.5 to 20%, Cu: 1 to 3%, the remainder of iron (Fe) and other inevitable impurities, and satisfies the following equation (1).
  • the unit is % by weight.
  • the content of C is 0.07 to 0.2%.
  • Carbon (C) is a strong austenite phase stabilizing element, and it is desirable to add 0.07% or more to increase the material strength by solid solution strengthening.
  • a carbide-forming element such as Cr effective for corrosion resistance to lower the Cr content around the grain boundaries to lower the corrosion resistance, and the upper limit can be limited to 0.2%.
  • the content of N is 0.15 to 0.4%.
  • Nitrogen (N) is a strong austenite phase stabilizing element and is an essential element in steels that do not contain Ni. It is desirable to add 0.15% or more in the present disclosure. However, if the content is excessive, surface defects due to nitride precipitation and nitrogen pores may be generated, and the upper limit may be limited to 0.4%.
  • the content of Si is 0.8 to 2%.
  • Silicon (Si) is an element useful for deoxidation, and when Ni is not added, it has an effect of improving corrosion resistance, so it is preferable to add 0.8% or more. However, if the content is excessive, the mechanical properties related to impact toughness are reduced, and the upper limit can be limited to 2%.
  • the content of Mn is 16 to 22%.
  • Manganese (Mn) is a core element that is essential for stabilization of the austenite phase when Ni is not added, and it is preferable to add 16% or more. However, if the content is excessive, surface defects may occur, and the upper limit may be limited to 22%.
  • the content of S is 0.01% or less.
  • S Sulfur
  • MnS becomes a starting point of corrosion and reduces corrosion resistance, so it is preferable to limit it to 0.01% or less.
  • the content of Cr is 12.5 to 20%.
  • Chromium (Cr) is the most contained element of the corrosion resistance improving element of stainless steel, and it is preferable to add 12.5% or more to express corrosion resistance.
  • Cr is a ferrite stabilizing element. As the Cr content increases, the ferrite fraction increases to inhibit austenite stabilization.
  • the upper limit can be limited to 20%.
  • the content of Cu is 1 to 3%.
  • Copper (Cu) is an essential element in the present disclosure, such as Mn, which increases the austenite phase stability and improves corrosion resistance.
  • copper (Cu) is added together with Mn to be dissolved in the passivation film to increase the surface conductivity, so it is preferable to add 1% or more.
  • the content is excessive, the moldability is rather deteriorated, and the upper limit can be limited to 3%.
  • Nickel (Ni) is treated as an impurity in the present disclosure because its elution and formability are deteriorated when added in small amounts.
  • the remaining component of the present disclosure is iron (Fe).
  • Fe iron
  • impurities that are not intended from the raw material or the surrounding environment can be inevitably mixed, and therefore cannot be excluded. Since these impurities are known to anyone skilled in the ordinary manufacturing process, they are not specifically mentioned in this specification.
  • austenitic stainless steel which is used for electronic parts, requires processes such as plate forming and deep drawing.
  • a deformed structure having a deformation amount of about 50% or more is formed, and non-magnetic properties must be maintained even in these deformed portions.
  • the permeability p of the steel applied to the parts should be 1.005 or less for normal operation. To satisfy this, it is necessary to control the content of ⁇ -ferrite formed during solidification of the steel.
  • ⁇ -ferrite present in the microstructure of austenitic stainless steel becomes magnetic due to the characteristics of the structure having a body-centered cubic structure, and austenite does not become magnetic due to the face-centered cubic structure. Therefore, it is possible to obtain a magnetic property of a desired size by controlling the fraction of ⁇ -ferrite, and in the case of non-magnetic steel, it is necessary to make the fraction of ⁇ -ferrite as low as possible or eliminate the fraction of ⁇ -ferrite.
  • the fraction of ⁇ -ferrite can be reduced by adding an austenite stabilizing element.
  • formation of ⁇ -ferrite can be suppressed by controlling Ni content useful for stabilizing austenite without deteriorating other physical properties.
  • Ni is a very expensive element, its range of use may be limited. Therefore, present disclosure attempted to secure the non-magnetic properties of austenitic stainless steel by controlling the content of Mn, Si, C, N without adding Ni.
  • the non-magnetic property can be expressed as a Ni equivalent (Nieq) value indicating austenite stability.
  • Ni equivalent refers to the minimum Ni content that does not form ⁇ -ferrite in a given compositional component, and can be expressed as follows.
  • Ni, Cr, Mn, Si, C, and N are weight % of each element.
  • the inventors of the present disclosure discovered that when the Ni equivalent value is 40 or more, the ferrite content measured after 70% cold working by simulating the actual severe molding part should satisfy 0.1% or less, so that the permeability is 1.005 or less, so that non-magnetic properties can be satisfied.
  • FIG. 1 is a graph showing the correlation of permeability according to Nieq. Referring to FIG. 1 , it can be seen that permeability satisfies 1.005 or less after 70% cold deformation of austenite stainless steel when the Ni equivalent is 40 or more.
  • the cold-rolled annealing plate of austenitic stainless steel may satisfy a yield strength of 450 Mpa or more and a hardness (Hv) value of 215 or more, expressed by the following equation (2).
  • C, N, Cu, Mn are weight % of each element.
  • the yield strength prediction equation including C, N and Cu content represented by equation (2), reflects the strength of the steel well, and have found that when the range of equation (2) is 450 or more, the desired strength can be secured.
  • FIG. 2 is a graph showing the correlation of yield strength (MPa) according to Nieq.
  • the yield strength of the cold rolled annealing plate of austenite stainless steel satisfies 450 Mpa or more.
  • austenitic stainless steel may satisfy a stacking fault energy represented by the following equation (3) of 41 mJ/m 2 or more.
  • Stacking fault energy (SFE, mJ/m 2 ) of the austenite phase is known to control the deformation mechanism of the austenite phase.
  • the stacking fault energy of the austenite phase indicates the degree to which the plastic deformation energy added from the outside contributes to the deformation of the austenite phase in the case of austenitic stainless steel in a single phase.
  • the lower the stacking fault energy the more the strain induced martensite phase that contributes to the work hardening of the steel increases after the formation of the epsilon martensite phase in the austenite phase.
  • a strain induced martensite phase is formed after the epsilon martensite phase is formed in the austenite phase, or a strain induced martensite phase is formed after mechanical twinning is formed in the austenite phase.
  • austenitic stainless steel may have a Cu+Mn content of 0.2% or more in a region within 2 nm from the surface layer.
  • stainless steel was produced through 50 kg ingot casting while changing the content of each component of the steel. After heating the ingot at 1250° C. for 3 hours, hot rolling was performed to produce a 4 mm thick hot rolled material. The hot rolled material was cold rolled, processed to a final thickness of 2.5 mm, annealed at 1100° C. for 30 seconds in the air, and pickled.
  • Yield strength (YS, Mpa) was measured through a tensile test on the specimen prepared in this way and compared with the yield strength prediction equation.
  • hardness Hv was measured through a Vickers hardness test.
  • the 2.5 mm cold rolled specimen was cold rolled at a cold reduction ratio of 70% to simulate the non-magnetic and surface resistance properties of a molded article made of an actual electronic parts material, thereby producing a cold rolled sheet having a thickness of 0.75 mm.
  • the ferrite content (%) of the manufactured cold rolled sheet was measured using a ferrite scope device, and permeability was measured using a permeability measurement device (FERROMASTER).
  • Mn+Cu (% by weight) in the passivation film at 2 nm from the surface layer of the cold rolled sheet was analyzed by using a Glow Discharge Spectrometer (GDS) analysis equipment.
  • GDS Glow Discharge Spectrometer
  • the surface resistance was expressed as a surface resistance value by measuring the resistance with a DC 4 terminal method by placing a gold-plated Cu-plate (area 2 cm 2 ) on the top/bottom of a cold rolled plate and applying a pressure of 10 N/cm 2 .
  • the surface resistance measurement criterion was evaluated as being good if the surface resistance was less than 10 m ⁇ cm 2 , and insufficient if it was 10 m ⁇ cm 2 or more.
  • SFE stacking fault energy
  • FIG. 1 is a graph showing the correlation of permeability according to Nieq.
  • the Nieq value represented by equation (1) is greater than or equal to 40 and the permeability is 1.005 or less compared to comparative examples, and thus it can be confirmed that the non-magnetic property is satisfied.
  • FIG. 2 is a graph showing the correlation of yield strength (MPa) according to Nieq.
  • the Nieq value represented by equation (1) is 40 or more, and the yield strength is 450 MPa or more and the hardness is 215 Hv or more, as compared with comparative examples.
  • the difference between the prediction equation of yield strength and the measured value of yield strength is minimal, so that equation (2) reflects the strength of austenitic stainless steel well.
  • the stacking fault energy (SFE) value was 41 mJ/m 2 or more as compared with Comparative Examples, and it was possible to suppress the formation of the martensite phase after plastic deformation, thereby ensuring ductility, and in the region within 2 nm from the surface layer, the Cu+Mn content is 0.2% or more and concentration of Cu and Mn occurs, so that the surface resistance is measured to be 10 m ⁇ cm 2 or less. That is, it can be confirmed that the surface conductivity is improved.
  • SFE stacking fault energy
  • Comparative Example 1 Ni is contained 8.1%, but the Mn content was excessively low at 1.5%, and the Nieq value was less than 40.
  • the Nieq value was 23.745, which was outside the present disclosure range, and the permeability is 5.2, it shows magnetism, so that high strength of 450 MPa or more and desired surface conductivity could not be secured.
  • the Nieq value was 30.38, which is less than 40, and the permeability was 2.5, so that the desired non-magnetic property could not be secured, and high-strength properties of 450 MPa or more could not be secured.
  • the austenitic stainless steel according to an embodiment of the present disclosure controls the content element without adding Ni to suppress strain induced martensite, and controls the ⁇ -ferrite content during solidification, thereby increasing strength and surface conductivity, while ensuring non-magnetic properties.
  • the non-magnetic austenitic stainless steel with improved surface conductivity according to embodiments of the present disclosure is applicable to materials for electronic parts.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Heat Treatment Of Sheet Steel (AREA)
US16/770,244 2017-12-20 2018-10-05 Non-magnetic austenitic stainless steel having improved strength and surface conductivity Pending US20200370154A1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
KR10-2017-0176559 2017-12-20
KR1020170176559A KR102020507B1 (ko) 2017-12-20 2017-12-20 강도, 표면전도성이 향상된 비자성 오스테나이트계 스테인리스강
PCT/KR2018/011762 WO2019124689A1 (ko) 2017-12-20 2018-10-05 강도, 표면전도성이 향상된 비자성 오스테나이트계 스테인리스강

Publications (1)

Publication Number Publication Date
US20200370154A1 true US20200370154A1 (en) 2020-11-26

Family

ID=66993626

Family Applications (1)

Application Number Title Priority Date Filing Date
US16/770,244 Pending US20200370154A1 (en) 2017-12-20 2018-10-05 Non-magnetic austenitic stainless steel having improved strength and surface conductivity

Country Status (6)

Country Link
US (1) US20200370154A1 (ja)
EP (1) EP3705595A4 (ja)
JP (1) JP6983321B2 (ja)
KR (1) KR102020507B1 (ja)
CN (1) CN111492081B (ja)
WO (1) WO2019124689A1 (ja)

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6313692A (ja) * 1986-07-05 1988-01-20 Kobe Steel Ltd オ−ステナイト系ステンレス鋼溶接用ワイヤ
US20110286879A1 (en) * 2009-02-27 2011-11-24 Nippon Yakin Kogyo Co., Ltd. HIGH-Mn AUSTENITIC STAINLESS STEEL AND METAL PARTS FOR CLOTHING ORNAMENT

Family Cites Families (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3904401A (en) * 1974-03-21 1975-09-09 Carpenter Technology Corp Corrosion resistant austenitic stainless steel
JPS5891160A (ja) * 1981-11-24 1983-05-31 Sumitomo Metal Ind Ltd 連続鋳造用非磁性鋼ロ−ル及びその製造方法
US4822556A (en) * 1987-02-26 1989-04-18 Baltimore Specialty Steels Corporation Austenitic stainless steel combining strength and resistance to intergranular corrosion
US5094812A (en) * 1990-04-12 1992-03-10 Carpenter Technology Corporation Austenitic, non-magnetic, stainless steel alloy
JP3486936B2 (ja) * 1993-12-08 2004-01-13 セイコーエプソン株式会社 時計外装部品用材料および時計用外装部品
JPH09195007A (ja) * 1996-01-19 1997-07-29 Kawasaki Steel Corp 耐食性に優れたＣｒ−Ｍｎ−Ｎ系オーステナイトステンレス鋼
US5904812A (en) * 1997-06-16 1999-05-18 Kimberly-Clark Worldwide, Inc. Calendered and embossed tissue products
DE102006033973A1 (de) * 2006-07-20 2008-01-24 Technische Universität Bergakademie Freiberg Nichtrostender austenitischer Stahlguss und seine Verwendung
CN100554480C (zh) * 2007-10-10 2009-10-28 江苏省方通新型不锈钢制品股份有限公司 铬锰铜钼系奥氏体耐蚀耐磨不锈钢
CN101503751B (zh) * 2009-03-26 2010-06-16 张国宝 卡电水浴钢丝淬火热处理方法
CN103667947B (zh) * 2013-11-29 2016-03-30 江阴市恒润重工股份有限公司 无镍奥化体不锈钢的制造工艺
PL2924131T3 (pl) * 2014-03-28 2020-02-28 Outokumpu Oyj Austenityczna wysokomanganowa stal nierdzewna
JP6560881B2 (ja) * 2015-03-26 2019-08-14 日鉄ステンレス株式会社 極低透磁率ステンレス鋼線材、ならびに耐久性に優れる鋼線、異形線
EP3147378A1 (fr) * 2015-09-25 2017-03-29 The Swatch Group Research and Development Ltd. Acier inoxydable austénitique sans nickel
CN105839022B (zh) * 2016-03-31 2021-04-09 宝钢德盛不锈钢有限公司 一种高硬度无磁无镍不锈钢及其制造方法
CN106399854B (zh) * 2016-06-23 2018-10-02 宝山钢铁股份有限公司 抗应力腐蚀开裂优良的高锰非磁性钢板及其制造方法

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6313692A (ja) * 1986-07-05 1988-01-20 Kobe Steel Ltd オ−ステナイト系ステンレス鋼溶接用ワイヤ
US20110286879A1 (en) * 2009-02-27 2011-11-24 Nippon Yakin Kogyo Co., Ltd. HIGH-Mn AUSTENITIC STAINLESS STEEL AND METAL PARTS FOR CLOTHING ORNAMENT

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
Mechanical Engineer "Cold Working", December 09, 2011, URL: <http://sainsmechanical.blogspot.com/2011/12/cold-working.html>, Pgs. 1-11 (Year: 2011) *
Ogawa et al., JP63013692A machine translation printed November 03, 2022, January 20, 1988, entire translation (Year: 1988) *
Takano et al., JP 2016183396 A Google Patents machine translation printed on November 8, 2022 with human translation of table captions of November 07, 2022, October 20, 2016, entire translation (Year: 2016) *

Also Published As

Publication number Publication date
JP6983321B2 (ja) 2021-12-17
WO2019124689A1 (ko) 2019-06-27
CN111492081B (zh) 2021-11-19
KR20190074873A (ko) 2019-06-28
EP3705595A1 (en) 2020-09-09
JP2021507103A (ja) 2021-02-22
CN111492081A (zh) 2020-08-04
KR102020507B1 (ko) 2019-09-10
EP3705595A4 (en) 2020-09-09

Similar Documents

Publication Publication Date Title
KR101420035B1 (ko) 프레스 부재 및 그 제조 방법
US20220010392A1 (en) Nonmagnetic austenitic stainless steel and manufacturing method therefor
US20200299816A1 (en) Non-magnetic austenitic stainless steel having excellent corrosion resistance and manufacturing method therefor
JP2010215953A (ja) オーステナイト系ステンレス鋼およびオーステナイト系ステンレス鋼板の製造方法
EP3126537B1 (en) Dual-phase stainless steel
EP3559295B1 (en) An object comprising a duplex stainless steel and the use thereof
KR20150074697A (ko) 저 니켈 함유 스테인리스강
JPWO2014157146A1 (ja) オーステナイト系ステンレス鋼板およびそれを用いた高強度鋼材の製造方法
US11952649B2 (en) High-strength stainless steel
KR101356951B1 (ko) 고경도 마르텐사이트계 스테인리스강 및 그 제조방법
KR102448742B1 (ko) 비자성 오스테나이트계 스테인리스강
US20200370154A1 (en) Non-magnetic austenitic stainless steel having improved strength and surface conductivity
CN112789365B (zh) 具有改善的强度的奥氏体不锈钢
JP6111109B2 (ja) 時効硬化特性に優れた低Ｎｉオーステナイト系ステンレス鋼板およびその製造方法
KR102170945B1 (ko) 피로수명이 우수한 오스테나이트계 스테인리스강 및 그 제조방법
JP2003082445A (ja) 加工性に優れた非磁性ステンレス鋼
JP2000129400A (ja) 強度・靱性・ばね特性の良好なマルテンサイト系ステンレス鋼焼鈍鋼材
JP4640628B2 (ja) 優れた冷間加工性と高い疲労強度をもつ析出硬化型マルテンサイト系鋼
KR101587700B1 (ko) 린 듀플렉스 스테인리스강
KR102463015B1 (ko) 열간가공성이 우수한 고강도 오스테나이트계 스테인리스강
US20230287549A1 (en) Austenitic stainless steel with improved deep drawing
US20230151470A1 (en) Non-magnetic austenitic stainless steel
KR20160080304A (ko) 심가공 특성이 우수한 듀플렉스 스테인리스강
JPH07316744A (ja) 冷間加工性に優れたマルテンサイト系ステンレス鋼線材とその製造方法
KR20140073473A (ko) 비자성 고강도 고망간 강판 및 그 제조방법

Legal Events

Date Code Title Description
AS Assignment

Owner name: POSCO, KOREA, REPUBLIC OF

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:KIM, JONG-HEE;KIM, KWANG MIN;SEO, BO-SUNG;AND OTHERS;REEL/FRAME:052863/0014

Effective date: 20200603

STPP Information on status: patent application and granting procedure in general

Free format text: APPLICATION DISPATCHED FROM PREEXAM, NOT YET DOCKETED

STPP Information on status: patent application and granting procedure in general

Free format text: DOCKETED NEW CASE - READY FOR EXAMINATION

STPP Information on status: patent application and granting procedure in general

Free format text: NON FINAL ACTION MAILED

STPP Information on status: patent application and granting procedure in general

Free format text: RESPONSE TO NON-FINAL OFFICE ACTION ENTERED AND FORWARDED TO EXAMINER

STPP Information on status: patent application and granting procedure in general

Free format text: FINAL REJECTION MAILED

STPP Information on status: patent application and granting procedure in general

Free format text: DOCKETED NEW CASE - READY FOR EXAMINATION

STPP Information on status: patent application and granting procedure in general

Free format text: NON FINAL ACTION MAILED

STPP Information on status: patent application and granting procedure in general

Free format text: RESPONSE TO NON-FINAL OFFICE ACTION ENTERED AND FORWARDED TO EXAMINER

STPP Information on status: patent application and granting procedure in general

Free format text: FINAL REJECTION MAILED

AS Assignment

Owner name: POSCO HOLDINGS INC., KOREA, REPUBLIC OF

Free format text: CHANGE OF NAME;ASSIGNOR:POSCO;REEL/FRAME:061561/0705

Effective date: 20220302

AS Assignment

Owner name: POSCO CO., LTD, KOREA, REPUBLIC OF

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:POSCO HOLDINGS INC.;REEL/FRAME:061774/0129

Effective date: 20221019

STPP Information on status: patent application and granting procedure in general

Free format text: DOCKETED NEW CASE - READY FOR EXAMINATION

STPP Information on status: patent application and granting procedure in general

Free format text: NON FINAL ACTION MAILED

STPP Information on status: patent application and granting procedure in general

Free format text: ADVISORY ACTION MAILED

STPP Information on status: patent application and granting procedure in general

Free format text: NON FINAL ACTION MAILED

STPP Information on status: patent application and granting procedure in general

Free format text: RESPONSE TO NON-FINAL OFFICE ACTION ENTERED AND FORWARDED TO EXAMINER

STPP Information on status: patent application and granting procedure in general

Free format text: FINAL REJECTION MAILED

STPP Information on status: patent application and granting procedure in general

Free format text: ADVISORY ACTION MAILED