EP0241553A1 - Hochfester rostfreistahl und dessen herstellung - Google Patents

Hochfester rostfreistahl und dessen herstellung Download PDF

Info

Publication number
EP0241553A1
EP0241553A1 EP85905113A EP85905113A EP0241553A1 EP 0241553 A1 EP0241553 A1 EP 0241553A1 EP 85905113 A EP85905113 A EP 85905113A EP 85905113 A EP85905113 A EP 85905113A EP 0241553 A1 EP0241553 A1 EP 0241553A1
Authority
EP
European Patent Office
Prior art keywords
steel
temperature
rolling
stainless steel
high strength
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.)
Granted
Application number
EP85905113A
Other languages
English (en)
French (fr)
Other versions
EP0241553A4 (de
EP0241553B1 (de
Inventor
Yoshinobu Honkura
Yoshihiro 3-8 Togane Nakajima
Touru Matsuo
Koji Murata
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.)
Aichi Steel Corp
Original Assignee
Aichi Steel Corp
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 Aichi Steel Corp filed Critical Aichi Steel Corp
Publication of EP0241553A1 publication Critical patent/EP0241553A1/de
Publication of EP0241553A4 publication Critical patent/EP0241553A4/de
Application granted granted Critical
Publication of EP0241553B1 publication Critical patent/EP0241553B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime 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
    • C22C38/001—Ferrous alloys, e.g. steel alloys containing N
    • 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
    • C21D8/005—Modifying the physical properties by deformation combined with, or followed by, heat treatment of ferrous 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
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/54—Ferrous alloys, e.g. steel alloys containing chromium with nickel with boron
    • 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
    • C22C38/58—Ferrous alloys, e.g. steel alloys containing chromium with nickel with more than 1.5% by weight of manganese

Definitions

  • This invention relates to high strength, corrosion resistant austenitic stainless steel for use in chemical, seawater, nuclear power plants, etc.
  • Austenitic stainless steel is in wide use as it offers excellent corrosion resistance - heat resistance, workability and mechanical properties.
  • SUS304, SUS316, SUS304L and SUS316L are typical of the sort.
  • SUS316LN, 316N, 316L, 316, 304LN, 304N 1 , 304 and 304L do not have a sufficient strength, and SUS304N 2 has problems and disadvantages in that cracks are produced during hot working and sufficient corrosion resistance is not obtained. Accordingly, they have not yet been put to practical use.
  • SUS304N, SUS304N 2 and SUS316N are inferior in intergranular corrosion resistance, sensitivity to anti-stress corrosion cracking. Furthermore, problematical is sharp reduction in their corrosion resistance after welding.
  • the present invention is intended to remedy the shortcomings of conventional stainless steel and has succeeded in not only providing satisfactory strength with, and improving the corrosion resistance of, austenitic stainless steel by adding a proper quantity of N, Nb, restricting the quantity of an impurity B and decreasing C content but also increasing the strength further by subjecting the steel to controlled rolling or thus rolled steel to thermo-mechanical treatment such as low temperature solution heat treatment.
  • the present inventors have studied the effects of C, N, Nb, B and roll finishing temperatures on the strength and corrosion resistance of austenitic stainless steel and found in the first place that, as shown in Fig. 1, intergranular corrosion resistance greater than that of SUS304L can be obtained by simultaneously adding 0.15 - 0.28% of N and 0.05 - 0.25% of Nb and limiting C to 0.03% or lower and B to 20 ppm.
  • a first example of steel embodying the present invention contains 0.03% or lower by weight C (hereinafter % refers to % by weight), 2.00% or lower of Si, 5.0% or lower of Mn, 0.030% or lower of S, 16 - 20% of Cr, 6 - 13% of Ni, 0.15 - 0.28% of N, 0.05 - 0.25% of Nb, 0.0020% or lower of B, remaining Fe and impurity elements.
  • a second example of steel according to the present invention contains either or both of 4% or lower of Mo and 4% or lower of Cu in addition to the elements contained in the first example or otherwise 0.005% or lower of S so as to improve the corrosion resistance of the first example.
  • a third example of steel according to the present invention contains either or both of 0.030-0.080% of S and 0.005 - 0.080% of Se to improve the machinability of the first example.
  • seventh and nineth examples of steel according to the present invention are obtained by heating the first, second and third examples of steel according to the present invention to 950 - 1,300°C, then rolling them at rolling temperatures of 900 - 1,250°C, controlling the roll finishing temperature so that it may be within the range of 900 - 1,000°C, subsequently cooling them at a rate of 4°C/min or higher, setting the total reduction quantity at 30% or higher, letting them have recrystallized microstructure and a proof stress of greater than 50kg/mm2 to improve the strength of the first, second and third examples.
  • Fifth, eighth and tenth examples of steel according to the present invention are obtained by heating the first, second and third examples according to the present invention to 950 - 1,300°C, then rolling them at rolling temperatures of 600 - 1,250°C, controlling the roll finishing temperature so that it may be within the range of 600 - 900°C, subsequently cooling them at a rate of 4°C/min or higher, setting the total reduction quantity at 30% or higher, letting them have unrecrystallized reduced structure and a proof stress of greater than 60 kg/mm 2 to improve the strength of the first, second and third examples.
  • Sixth example of steel according to the present invention is obtained by heating the first example according to the present invention to 950 - 1,300°C, then rolling it at rolling temperatures of 900 - 1,250°C, controlling the roll finishing temperature so that it may be lower than 1,000°C, subsequently subjecting it to low temperature solution heat treatment at 900 - 1,010°C, letting it have a grain size number of greater than 7.5 and a proof stress of greater than 40 kg/mm2 to improve the strength of the first example.
  • the element C in the present invention is important because it reduces the corrosion resistance after controlled rolling, and hot workability during controlled rolling to a large extent; consequently, it must be decreased to 0.03% or lower, so that an upper limit is set at 0.03%.
  • the element Si is added as a deoxidizer and also used to improve the strength, however it causes cracking at high temperatures at the time of welding and reduce the quantity N of the solid solution at the time of solidification; accordingly, it must be decreased to 2.0% or lower with 2.0% as an upper limit to obtain good steel ingots.
  • the element Mn is added as a deoxidizer and used to increase the solubility of N but it will impair the corrosion resistance and hot workability if the content of Mn increases; consequently, the upper limit is set at 5.0%.
  • Cr is the basic element of stainless steel and over 16% of it is at least required to provide superior corrosion resistance. However, because the excessive content of Cr will damage the balance between 6/y structure at high temperatures, the upper limit is set at 20%.
  • Ni is the basic element of austenitic stainless steel and over 6% of it is required to obtain excellent corrosion resistance and austenitic structure. However, because the excessive content of Ni will cause weld cracks and reduce hot workability and corrosion resistance after controlled rolling, the upper limit is set at 13%.
  • N is the most important-reinforcing element according to the present invention since it has penetration type solution strengthening action, crystal grain micronizing action resulting from Nb (C, N) precipitation and precipitation accelerating action, and contributes to improvement in corrosion resistance after controlled rolling.
  • the lower limit was set at 0.15%.
  • the upper limit is set at 0.28%.
  • Nb is an important element in the present invention for fixing the remaining C in the form of NbC, improving corrosion resistance after controlled rolling, rifining of crystal grain because of Nb (C, N) precipitation and increasing strength after controlled rolling; thus over 0.05% of Nb content is at least required.
  • Nb is an expensive element and, because the excessive content of it will damage hot workability, the upper limit is set at 0.25%.
  • B is the element to reduce the intergranular corrosion resistance of the steel according to the present invention and, also to reduce the corrosion resistance after controlled rolling:
  • the upper limit is set at 0.0020% and preferably 0.005% or lower.
  • Both of Mo and Cu are the elements to improve the corrosion resistance of the steel according to the present invention.
  • Mo and Cu are expensive elements and the content exceeding 4% will damage hot workability.
  • the upper limits are set at 4% each.
  • S is the element to improve corrosion resistance provided that its content is reduced by a large amount, ductility and toughness (particularly in the direction perpendicular to that of rolling) after controlled rolling.
  • S and Se are the elements used to improve the machinability of the steel according to the present invention, and 0.030% or higher of S and 0.005% or higher of Se must be contained therein. However, because hot workability and corrosion resistance will decrease if the content of each of S and Se exceeds 0.080%, the upper limit is set at 0.080%.
  • the reason why the heating temperatures were set at 950 - 1,300°C during controlled rolling is to reduce deformation resistance at the controlled rolling.
  • the rolling will become difficult because of large deformation resistance if the temperature is lower than 950°C and, if it exceeds 1,300°C, the rolling will also become difficult because partial intergranular fusion is developed or coarse crystal grains are produced.
  • the roll finishing temperatures are set at 900 - 1,000°C so as to control the strength of the steel according to the present invention; the lower the roll finishing temperature, the greater the strength thereof becomes.
  • the temperature exceeding 1,000°C will make recrystallized grains coarse and satisfactory strength unavailable, whereas the temperature lower than 900°C will make recrystallized microstructure unavailable and act to form unrecrystallized reduced structure, so that ductility and toughness in the direction perpendicular to that of rolling are reduced.
  • the roll finishing temperatures are set at 600 - 900°C because unrecrystallized reduced structure will be present at lower than 900°C and the strength of the steel will increase as the roll-finishing temperature becomes lower. On the other hand, its ductility and toughness will decrease. Accordingly, it is preferred to set the percentage of S at 0.005 or lower during rolling at 600 - 900°C.
  • the temperature lower than 600°C is lower than the recovery temperature of the steel according to the present invention, the deformation resistance during rolling will be raised sharply and thus undesirable because rolling becomes difficult.
  • the low temperature solution heat treatment temperatures are set at 900 - 1,010°C because the solid solubility of C is possible with heat addition at 900 - 1,010°C and, when the recrystallization temperature is higher than 900°C, the crystal grain size, if treated at lower temperatures, will be minimized, whereas the strength will be increased.
  • C will not be solid - soluble nor recrystallized at temperatures lower than 900°C, whereas its crystal grain will become as coarse as 7.5 or smaller if the temperature exceeds 1,010°C and the strength will thus decrease.
  • the reason why the cooling rate after rolling is set at higher than 4°C/min is that the intergranular precipitation of Cr 23 C 6 or Cr 2 N will be caused by slow cooling at a rate lower than 4°C/min and the corrosion resistance will decrease.
  • the reason why the total reduction ratio within the rolling temperature range of 900°C - 1,250°C is set at 30% is that the desired structure is unobtainable because the scarcity of the lattice defect and the accumulated energy introduced into the crystal as the result of working will allows coarse structure to remain while heated if the total reduction ratio is lower than 30%.
  • Table 1 shows chemical components of test pieces.
  • Table 2 shows the strength, corrosion resistance and hot workability of the examples A - Q of steel subjected to solution heat treatment (1,050°C x 30 min ⁇ W, Q) shown in Table 1.
  • JIS No. 4 test pieces were used to measure proof stress.
  • step structure is represented by 0
  • DUAL composite structure
  • DITCH switch structure
  • the pitting corrosion potential in an aqueous solution containing 3.5% NaCl at 30°C was measured.
  • the examples A, C of conventional steel were superior in hot workability but inferior in proof stress, e.g., 25.0, 22.8 kg/mm 2
  • the examples A, C are inferior in inter granular corrosion resistance, sensitivity to anti-stress corrosion cracking, and the portion affected by welding heat.
  • the example B was superior in hot workability and the corrosion resistance of the base material and the portion affected by welding heat but inferior in proof stress, e.g., affected by welding heat but inferior in strength, e.g., 25.2 kg/mm2, intergranular corrosion resistance, and sensitivity to anti-stress corrosion cracking.
  • the example D was superior in sensitivity to anti-stress corrosion cracking, hot workability and the corrosion resistance of the base material and the portion affected by welding heat but inferior in proof stress, e.g., 23.4 kg/mm2 and intergranular corrosion resistance.
  • the example E prepared by adding 0.22% of N to the example A showed substantial inprovement in proof stress., e.g., 32.1 kg/mm2 compared with the example A but a shortage of strength as high strength stainless steel.
  • the example F prepared by adding 0.10% of Nb to the example E showed further improvement in proof stress, e.g., 40.7 kg/mm2 and had satisfactory strength as high strength stainless steel but indicated reduced hot workability.
  • the example G prepared by adding 0.17% of N to the example B showed improvement in proof stress, e.g., 39.2 kg/mm 2 and excellent strength but still reduced intergranular corrosion resistance and sensitivity anti-stress corrosion cracking in addition to reduced hot workability like the
  • the examples'H - Q of the steel according to the present invention being prepared by simultaneously adding 0.15 - 0.28% of N and 0.05 - 0.25% of Nb and limiting the quantity of C to 0.03% or lower and the quantity of B to 20 ppm or less, showed such strength as a stress proof of 48 kg/mm 2 or greater, STEP (step structure) respecting intergranular corrosion resistance, no cracking regarding sensitivity to anti-stress corrosion cracking despite immersion for 50 Hr, no reduction in hot workability unlike the conventional steet, a contraction of area of over 70%, and excellent corrosion resistance of the base material and the portion affected by welding heat at 0.3V or higher.
  • each of the steel according to the present invention is superior in all of the strength, intergranular corrosion resistance, sensitivity to anti-stress corrosion cracking, hot workability, the corrosion resistance of the base, material and the portion affected by welding heat.
  • Table 3 illustrates the strength and corrosion resistance of the examples A, C, E, F, J, M and P shown in Table 1 and, as for those subjected to low temperature solution heat treatment, and their crystal grain sizes.
  • the flat steel by 10 x 40 mm was heated to 1,150°C and then rolled with the roll finishing temperature controlled at about 950°C or 800°C, before being cooled at 50°C/min or higher and the total reduction ratio of 96%.
  • the steel thus heated and rolled with the roll finishing temperature controlled at .950°C was cooled at 50°C/min and the total reduction ratio of 96% and then subjected to low temperature solution heat treatment for holding it at 980°C x 30 min.
  • the roll finishing temperature controlled at 950°C or 800°C resulted, as shown in Table 3, in causing the proof stress of the example A to increase from 25 kg/mm 2 to 33, 42 kg/mm , that of the example C from 22.8 kg/mm2 to 25, 31 kg/mm 2 and that of that of the example E from 32.1 kg/mm 2 to 44, 53 kg/mm 2 but still failing to attaining the desired 50, 60 kg/mm2.
  • all of the examples A, C, E subjected to controlled rolling showed reduction in corrosion resistance by a large margin.
  • the roll finishing temperature controlled at 950°C allowed the examples J, M, P of the steel according to the present invention to have recrystallized microstructure and improved the proof stress of each from about 50 kg/mm 2 to 65 kg/mm 2 , whereas the roll finishing temperature controlled at 800°C permitted them to have uncrystallized reduced structure and considerably improved the proof stress of 2 each.up to about 77 kg/mm ; in other words, controlled rolling applied to the steel according to the present invention obviously acted to improve its proof stress by a large amount.
  • the examples J, M, P according to the present invention showed pitting corrosion potential equivalent to what was not subjected to controlled rolling and, unlike the conventional steel, no reduction in corrosion resistance because of the controlled rolling applied.
  • each of the examples J, M, P according to the present invention was allowed to have recrystallized microstructure with a crystal grain size of over 7.5 by that treatment and showed the proof stress raised up to over 50 kg/mm 2 and pitting corrosion potential roughly equivalent to what was subjected to solution heat treatment (1,050°C x 30 min + W,Q.) and no reduction in corrosion resistance due to controlled rolling and low temperature solution heat treatment.
  • the present invention relates to economical stainless steel and a process for manufacturing the same having high strength, e.g., over 35 kg/mm2 in terms of proof stress, the strength being improvable up to 50 kg/mm2 or greater and further 70 kg/mm2 or greater by controlled rolling; excellent corrosion resistance, particularly intergranular corrosion resistance and sensitivity to anti-stress corrosion clacking; pitting corrosion and acid resistance superior to SUS 304 ; corrosion resistance without being reduced after welding; excellent hot workability; and producibility through the same process as that of SUS 304 manufacture.
  • the corrosion resistance of the steel according to the present invention is made further improvable by adding Mo, Cu as occasion demands and its machinability is also improvable by adding small quantities of S, Se.
  • the steel according to the present invention is superior in strength and corrosion resistance and suitable for use as a high strength member in various plants such as chemical seawater and nuclear power plants.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Heat Treatment Of Steel (AREA)
EP85905113A 1985-10-15 1985-10-15 Hochfester rostfreistahl und dessen herstellung Expired - Lifetime EP0241553B1 (de)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/JP1985/000573 WO1987002388A1 (en) 1985-10-15 1985-10-15 High strength stainless steel, and process for its production

Publications (3)

Publication Number Publication Date
EP0241553A1 true EP0241553A1 (de) 1987-10-21
EP0241553A4 EP0241553A4 (de) 1989-01-18
EP0241553B1 EP0241553B1 (de) 1992-06-17

Family

ID=13846597

Family Applications (1)

Application Number Title Priority Date Filing Date
EP85905113A Expired - Lifetime EP0241553B1 (de) 1985-10-15 1985-10-15 Hochfester rostfreistahl und dessen herstellung

Country Status (3)

Country Link
EP (1) EP0241553B1 (de)
DE (1) DE3586247T2 (de)
WO (1) WO1987002388A1 (de)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0260022A2 (de) * 1986-08-30 1988-03-16 Aichi Steel Works, Ltd. Rostfreier Stahl mit guter Korrosionsbeständigkeit und guter Beständigkeit gegen Korrosion durch Seewasser und Verfahren zu seiner Herstellung

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100411286B1 (ko) * 1996-12-24 2004-04-03 주식회사 포스코 내식성및내후성이우수한고강도오스테나이트계스테인레스강및이를이용한강판제조방법

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS54151505A (en) * 1978-05-09 1979-11-28 Kobe Steel Ltd Austenitic stainless steel microcrystal grain generation
JPS558404A (en) * 1978-06-30 1980-01-22 Nippon Steel Corp Manufacture of austenitic stainless steel used in atmosphere of high-temperature and high-pressure water
JPS58144420A (ja) * 1982-02-19 1983-08-27 Kawasaki Steel Corp オ−ステナイト系ステンレス大型鍛鋼の製造方法
JPS6089518A (ja) * 1983-10-22 1985-05-20 Sumitomo Metal Ind Ltd オ−ステナイト系材料の製造方法
JPS6092422A (ja) * 1983-10-25 1985-05-24 Nippon Kokan Kk <Nkk> 亀裂開口変位の優れた含Νｉ低温用鋼の製造方法
JPS60100621A (ja) * 1983-11-07 1985-06-04 Nippon Steel Corp 高温強度の優れたオ−ステナイトステンレス鋼の製造方法
EP0154601A2 (de) * 1984-02-24 1985-09-11 MANNESMANN Aktiengesellschaft Verwendung einer korrosionsbeständigen austenitischen Legierung für mechanisch hoch beanspruchte, schweissbare Bauteile
JPS60208459A (ja) * 1984-03-30 1985-10-21 Aichi Steel Works Ltd 高強度ステンレス鋼およびその製造法

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5326215A (en) * 1976-08-23 1978-03-10 Daido Steel Co Ltd Free cutting steel with improved corrosion resistance
JPS5946287B2 (ja) * 1979-02-13 1984-11-12 住友金属工業株式会社 オ−ステナイト系ステンレス鋼の固溶化処理法
JPS5940901B2 (ja) * 1981-03-24 1984-10-03 日本ステンレス株式会社 耐食性オ−ステナイト系ステンレス鋼
JPS5825460A (ja) * 1981-08-07 1983-02-15 Nippon Stainless Steel Co Ltd ２次加工性および耐食性の良好な高強度オ−ステナイトステンレス鋼
JPS5881956A (ja) * 1981-11-10 1983-05-17 Aichi Steel Works Ltd オ−ステナイト系ステンレス鋼
JPS60197817A (ja) * 1984-03-19 1985-10-07 Nippon Kokan Kk <Nkk> 耐食性に優れた高降伏強度オ−ステナイト・ステンレス鋼材の製造方法

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS54151505A (en) * 1978-05-09 1979-11-28 Kobe Steel Ltd Austenitic stainless steel microcrystal grain generation
JPS558404A (en) * 1978-06-30 1980-01-22 Nippon Steel Corp Manufacture of austenitic stainless steel used in atmosphere of high-temperature and high-pressure water
JPS58144420A (ja) * 1982-02-19 1983-08-27 Kawasaki Steel Corp オ−ステナイト系ステンレス大型鍛鋼の製造方法
JPS6089518A (ja) * 1983-10-22 1985-05-20 Sumitomo Metal Ind Ltd オ−ステナイト系材料の製造方法
JPS6092422A (ja) * 1983-10-25 1985-05-24 Nippon Kokan Kk <Nkk> 亀裂開口変位の優れた含Νｉ低温用鋼の製造方法
JPS60100621A (ja) * 1983-11-07 1985-06-04 Nippon Steel Corp 高温強度の優れたオ−ステナイトステンレス鋼の製造方法
EP0154601A2 (de) * 1984-02-24 1985-09-11 MANNESMANN Aktiengesellschaft Verwendung einer korrosionsbeständigen austenitischen Legierung für mechanisch hoch beanspruchte, schweissbare Bauteile
JPS60208459A (ja) * 1984-03-30 1985-10-21 Aichi Steel Works Ltd 高強度ステンレス鋼およびその製造法

Non-Patent Citations (4)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN vol. 007, no. 263 (C-196) <1408> 24 November 1983 & JP 58 144420 A (KAWASAKI SEITETSU K.K.) 27 August 1983 *
PATENT ABSTRACTS OF JAPAN vol. 009, no. 233 (C-304) <1956> 19 September 1985 & JP 60 092422 A (NIPPOM KOKAN K.K.) 24 May 1985 *
PATENT ABSTRACTS OF JAPAN vol. 010, no. 071 (C-334) <2128> 20 March 1986 & JP 60 208459 A (AICHI SEIKOU K.K.) 21 October 1985 *
See also references of WO8702388A1 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0260022A2 (de) * 1986-08-30 1988-03-16 Aichi Steel Works, Ltd. Rostfreier Stahl mit guter Korrosionsbeständigkeit und guter Beständigkeit gegen Korrosion durch Seewasser und Verfahren zu seiner Herstellung
EP0260022B1 (de) * 1986-08-30 1991-10-23 Aichi Steel Works, Ltd. Rostfreier Stahl mit guter Korrosionsbeständigkeit und guter Beständigkeit gegen Korrosion durch Seewasser und Verfahren zu seiner Herstellung

Also Published As

Publication number Publication date
EP0241553A4 (de) 1989-01-18
DE3586247T2 (de) 1993-02-25
WO1987002388A1 (en) 1987-04-23
DE3586247D1 (de) 1992-07-23
EP0241553B1 (de) 1992-06-17

Similar Documents

Publication Publication Date Title
US4975131A (en) High strength hot worked stainless steel
EP1357198B1 (de) Wärme- und korrosionsbeständige austenitische Legierung, wärme- und druckbeständige Bauteile und Verfahren zu deren Herstellung
KR100605983B1 (ko) 내열스프링용 합금선
EP2199420B1 (de) Austenitischer edelstahl
KR900006605B1 (ko) 가공성이 우수하고 용접 연화가 없는 고강도 스테인레스 강재의 제조 방법
US4957701A (en) High-strength high-Cr ferritic heat-resistant steel
US5000801A (en) Wrought stainless steel having good corrosion resistance and a good resistance to corrosion in seawater
DE69204123T2 (de) Hitzebeständiges ferritisches Stahl mit hohem Chromgehalt und mit höhere Beständigkeit gegen Versprödung durch intergranuläre Ausscheidung von Kupfer.
JP4754362B2 (ja) 耐食性、耐力、低温靱性が良好なオーステナイト系ステンレス熱間圧延鋼材およびその製造方法
EP3693487A1 (de) Austenitischer edelstahl
US4847046A (en) Ultra-low temperature alloy and process for manufacturing the same
EP0241553A1 (de) Hochfester rostfreistahl und dessen herstellung
JP3328967B2 (ja) 靭性および耐応力腐食割れ性に優れたマルテンサイト系ステンレス鋼継目無鋼管の製造法
JP3746877B2 (ja) 耐食性とばね特性にすぐれたばね用ステンレス鋼線
JPH0830253B2 (ja) 加工性に優れた析出硬化型マルテンサイト系ステンレス鋼
JPS6199660A (ja) ラインパイプ用高強度溶接鋼管
JPH05320756A (ja) 耐海水性に優れた高強度オーステナイト系ステンレス鋼の製造方法
JP3218442B2 (ja) 耐遅れ破壊特性の優れた機械構造用鋼の製造方法
JP2001247930A (ja) 耐震性および耐火性に優れた圧延形鋼とその製造方法
JPH0726149B2 (ja) 高耐力ステンレス形鋼の製造方法
US4435231A (en) Cold worked ferritic alloys and components
JPH0114991B2 (de)
JPS60155652A (ja) 耐熱鋼
US5116570A (en) Stainless maraging steel having high strength, high toughness and high corrosion resistance and it&#39;s manufacturing process
JP2787044B2 (ja) 高強度ステンレス鋼およびその製造法

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 19870526

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): DE FR GB SE

A4 Supplementary search report drawn up and despatched

Effective date: 19890118

17Q First examination report despatched

Effective date: 19900322

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): DE FR GB SE

REF Corresponds to:

Ref document number: 3586247

Country of ref document: DE

Date of ref document: 19920723

ET Fr: translation filed
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
EAL Se: european patent in force in sweden

Ref document number: 85905113.8

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: SE

Payment date: 19950905

Year of fee payment: 11

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 19951030

Year of fee payment: 11

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 19951130

Year of fee payment: 11

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 19961007

Year of fee payment: 12

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SE

Effective date: 19961016

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Effective date: 19970630

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Effective date: 19970701

EUG Se: european patent has lapsed

Ref document number: 85905113.8

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 19971015

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 19971015