EP0057316B1 - Low interstitial, corrosion resistant, weldable ferritic stainless steel and process for the manufacture thereof - Google Patents
Low interstitial, corrosion resistant, weldable ferritic stainless steel and process for the manufacture thereof Download PDFInfo
- Publication number
- EP0057316B1 EP0057316B1 EP81305667A EP81305667A EP0057316B1 EP 0057316 B1 EP0057316 B1 EP 0057316B1 EP 81305667 A EP81305667 A EP 81305667A EP 81305667 A EP81305667 A EP 81305667A EP 0057316 B1 EP0057316 B1 EP 0057316B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- less
- stainless steel
- ferritic stainless
- corrosion resistant
- steel
- 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.)
- Expired
Links
- 229910001220 stainless steel Inorganic materials 0.000 title claims abstract description 26
- 238000005260 corrosion Methods 0.000 title claims abstract description 25
- 230000007797 corrosion Effects 0.000 title claims abstract description 25
- 238000000034 method Methods 0.000 title claims abstract description 15
- 230000008569 process Effects 0.000 title claims abstract description 14
- 238000004519 manufacturing process Methods 0.000 title claims description 5
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims abstract description 30
- 229910000831 Steel Inorganic materials 0.000 claims abstract description 25
- 239000010959 steel Substances 0.000 claims abstract description 25
- 239000010955 niobium Substances 0.000 claims abstract description 21
- GUCVJGMIXFAOAE-UHFFFAOYSA-N niobium atom Chemical compound [Nb] GUCVJGMIXFAOAE-UHFFFAOYSA-N 0.000 claims abstract description 21
- 238000001816 cooling Methods 0.000 claims abstract description 18
- 239000010936 titanium Substances 0.000 claims abstract description 17
- 229910052719 titanium Inorganic materials 0.000 claims abstract description 17
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 claims abstract description 16
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims abstract description 16
- 229910052750 molybdenum Inorganic materials 0.000 claims abstract description 16
- 239000011733 molybdenum Substances 0.000 claims abstract description 16
- 229910052757 nitrogen Inorganic materials 0.000 claims abstract description 16
- 229910052799 carbon Inorganic materials 0.000 claims abstract description 15
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 14
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims abstract description 14
- 239000011651 chromium Substances 0.000 claims abstract description 11
- 229910052804 chromium Inorganic materials 0.000 claims abstract description 11
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 claims abstract description 10
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims abstract description 10
- 229910052759 nickel Inorganic materials 0.000 claims abstract description 7
- 229910052710 silicon Inorganic materials 0.000 claims abstract description 7
- 239000010703 silicon Substances 0.000 claims abstract description 7
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims abstract description 6
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 claims abstract description 6
- 229910052782 aluminium Inorganic materials 0.000 claims abstract description 6
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims abstract description 6
- 229910052802 copper Inorganic materials 0.000 claims abstract description 6
- 239000010949 copper Substances 0.000 claims abstract description 6
- 229910052717 sulfur Inorganic materials 0.000 claims abstract description 6
- 239000011593 sulfur Substances 0.000 claims abstract description 6
- 238000005097 cold rolling Methods 0.000 claims abstract description 5
- 229910052742 iron Inorganic materials 0.000 claims abstract description 5
- WPBNNNQJVZRUHP-UHFFFAOYSA-L manganese(2+);methyl n-[[2-(methoxycarbonylcarbamothioylamino)phenyl]carbamothioyl]carbamate;n-[2-(sulfidocarbothioylamino)ethyl]carbamodithioate Chemical compound [Mn+2].[S-]C(=S)NCCNC([S-])=S.COC(=O)NC(=S)NC1=CC=CC=C1NC(=S)NC(=O)OC WPBNNNQJVZRUHP-UHFFFAOYSA-L 0.000 claims abstract description 5
- 238000000137 annealing Methods 0.000 claims abstract description 4
- BHEPBYXIRTUNPN-UHFFFAOYSA-N hydridophosphorus(.) (triplet) Chemical compound [PH] BHEPBYXIRTUNPN-UHFFFAOYSA-N 0.000 claims abstract description 4
- 230000007704 transition Effects 0.000 claims description 10
- 238000003466 welding Methods 0.000 claims description 7
- 239000000203 mixture Substances 0.000 abstract description 9
- 239000004411 aluminium Substances 0.000 abstract 1
- 238000010791 quenching Methods 0.000 description 9
- 230000007423 decrease Effects 0.000 description 6
- 238000012360 testing method Methods 0.000 description 5
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 4
- LJAOOBNHPFKCDR-UHFFFAOYSA-K chromium(3+) trichloride hexahydrate Chemical compound O.O.O.O.O.O.[Cl-].[Cl-].[Cl-].[Cr+3] LJAOOBNHPFKCDR-UHFFFAOYSA-K 0.000 description 3
- 229910001182 Mo alloy Inorganic materials 0.000 description 2
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- 229910045601 alloy Inorganic materials 0.000 description 2
- 239000000956 alloy Substances 0.000 description 2
- 238000005336 cracking Methods 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 229910052698 phosphorus Inorganic materials 0.000 description 2
- 239000011574 phosphorus Substances 0.000 description 2
- 239000000047 product Substances 0.000 description 2
- 229910000599 Cr alloy Inorganic materials 0.000 description 1
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 239000010953 base metal Substances 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- 239000000788 chromium alloy Substances 0.000 description 1
- 238000003776 cleavage reaction Methods 0.000 description 1
- 230000001143 conditioned effect Effects 0.000 description 1
- 230000001627 detrimental effect Effects 0.000 description 1
- 239000012467 final product Substances 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 230000006698 induction Effects 0.000 description 1
- 230000002452 interceptive effect Effects 0.000 description 1
- 229910052748 manganese Inorganic materials 0.000 description 1
- 239000011572 manganese Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 230000000171 quenching effect Effects 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 230000007017 scission Effects 0.000 description 1
- 239000013535 sea water Substances 0.000 description 1
- 238000010583 slow cooling Methods 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
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
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/26—Ferrous alloys, e.g. steel alloys containing chromium with niobium or tantalum
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/22—Ferrous alloys, e.g. steel alloys containing chromium with molybdenum or tungsten
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/28—Ferrous alloys, e.g. steel alloys containing chromium with titanium or zirconium
Definitions
- the present invention relates to a low interstitial, corrosion resistant, weldable ferritic stainless steel with improved toughness and to a process for the manufacture thereof. More specifically, the present invention is directed to a low interstitial/corrosion resistant, Weldable ferritic stainless steel with a small addition of either columbium or titanium to improve the toughness when the maximum achievable cooling rate is limited.
- a ferritic stainless steel must have superior pitting and crevice corrosion resistance in order to be used in certain chemical environments as for example in power plants exposed to sea water, and pulp and paper process equipment.
- Stainless steel containing 29% chromium and 4% molybdenum are highly resistant to crevice corrosion. These steels require a low level of interstitials, for example a total carbon plus nitrogen content of less than 0.025% by weight, to have good post-welding ductility and intergranular corrosion resistance.
- Toughness is the ability of a metal to absorb energy by deforming plastically before fracturing.
- the transition temperature is the temperature at which the fracture which occurs from the impact is 50 percent shear (ductile) and 50 percent cleavage (brittle).
- the toughness of the 29% chromium - 4% molybdenum alloy is low compared to substantially lower chromium alloys of an equivalent carbon and nitrogen content because of the high alloy content.
- the toughness of the 29% chromium - 4% molybdenum alloy is improved by water-quenching to speed up the cooling process instead of the slower air-cooling.
- the water-quenching process is not possible or practical to use, so a method is needed to improve the toughness of the steel in those situations where the maximum cooling rate is limited.
- United States Patent No. 3,807,991 teaches the addition of between 13 and 29 times the amount of nitrogen or between 0.065% and 0.363% columbium to a steel of 1 % molybdenum for improved toughness and intergranular corrosion resistance in the air-cooled condition.
- An object of the present invention is to provide a low interstitial, corrosion resistant, weldable ferritic stainless steel with a high molybdenum content which exhibits improves toughness in heavier section thickness when the maximum achievable cooling rate is limited.
- a further object of the present invention is to provide a low interstitial, corrosion resistant, weldable ferritic stainless steel with a high molybdenum content which exhibits improved toughness due to a small addition of either columbium or titanium.
- this invention provides a low interstitial ferritic stainless steel which is corrosion resistant and weldable at room temperature.
- the improvement of the present invention being an addition of a small critical amount of columbium and/or titanium to improve the toughness of the steel in situations where water quenching is impossible or impractical.
- the present invention provides a low interstitial, corrosion resistant, weldable ferritic stainless steel with improved toughness characterized in that it consists of, by weight percent: 25.0%-35.G% chromium, 3.6%-5.6% molybdenum, less than 3% nickel, less than 2% manganese, less than 2.0% silicon, less than 0.5% aluminum, less than 0.50% copper, less than 0.050% phosphorus, less than 0.05% sulfur, less than 0.01 % carbon, less than 0.02% nitrogen, the sum of the carbon and nitrogen being less than 0.025%, 0.05-0.50% of columbium and/or titanium, and the balance of iron.
- the present invention further provides a process for the manufacture of ferritic stainless steel of improved toughness wherein said steel is hot rolled, annealed and cold-rolled to strip thickness, characterized in that the process comprises air-cooling from the annealing temperature before cold rolling a ferritic stainless steel consisting essentially of, by weight per cent: 25.0%-35.0% chromium, 3.6%-5.6% molybdenum, less than 3.0% nickel, less than 2.0% manganese, less than 2.0% silicon, less than 0.5% aluminum, less than 0.5% copper, less than 0.5% phosphorus, less than 0.05% sulfur, less than 0.01% carbon, less than 0.02% nitrogen, the sum of the carbon and nitrogen being less than 0.025%, 0.05%-0.50% of columbium and/or titanium, and the balance iron, so as to produce a steel with a Charpy impact transition temperature of below -17.8°C (0°F) as cold-rolled to a thickness of 1.575 mm (0.062 inches).
- Chromium and molybdenum are preferably present in respective amounts of 28.5% to -30.5% and 3.75% to 4.75%.
- Columbium and/or titanium is present preferably in the amount of 0.05% to 0.20%.
- Manganese and silicon are each usually present in amounts of less than 1%.
- Aluminum, copper, phosphorous, and sulfur are present usually in amounts of less than 0.1 %.
- Carbon and nitrogen are present preferably in amounts of less than 0.008% and 0.016% respectively.
- This invention relates to a low interstitial ferritic stainless steel having a chromium content of between 25.0% and 35.0% and a molybdenum content of between 3.6% and 5.6%.
- a small amount of columbium or titanium of between 0.05% and 0.20% is added to the steel composition to improve its toughness when the maximum achievable cooling rate is limited.
- the ingots were conditioned, heated to a temperature of 1121°C (2050°F) and hot rolled to a strip about 3.556 mm (0.140 in.) thick.
- the hot rolled band was annealed at a temperature of 1010°C (1850°F), and water-quenched and cold rolled to a thickness of 1.575 mm (0.062 in.).
- the strip was then annealed at a temperature of 1010°C (1850°F), water-quenched and TIG welded.
- the impact transition temperatures of the air-cooled specimens are higher than those of the water-quenched specimens it can be seen from Table II that the difference in impact transition temperatures of an air-cooled and a water-quenched 1.575 mm (0.062 in.) thick steel strip is less than 55°C (100°F). Whereas the difference in impact transition temperature for prior art compositions is 133°C (240°F).
- the impact transition temperature of the 1.575 mm (0.062 in.) steel strip of a composition according to the present invention is below -17.8°C (0°F) whereas that of prior art composition A is 54°C (130°F). It is essential that the impact transition temperature of such a steel strip be below room temperature so that the steel strip will not crack upon welding. Steels of prior art compositions had to be water-quenched before cold rolling in order to achieve the necessary toughness characteristics.
- the composition of this invention enables us to achieve good toughness characteristics by air-cooling the steel before cold-rolling instead.
- Corrosion tests were also performed on the 1.575 mm (0.062 in.) thick strip in the as welded condition and on the base metal specimens which were heat treated at 1232°C (2250°F) and air-cooled to simulate the heat affected zone upon welding a heavier thickness.
- the specimens 25.4 mmx50.8 mm (1 in.x2 in.) were exposed to a boiling solution of ferritic sulfate-50% sulfuric acid for 120 hours according to ASTM A262 Practice B for intergranular corrosion testing. The corrosion rates are given in Table Ill.
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Heat Treatment Of Steel (AREA)
- Heat Treatment Of Sheet Steel (AREA)
- Treatment Of Steel In Its Molten State (AREA)
- Pressure Welding/Diffusion-Bonding (AREA)
- Laminated Bodies (AREA)
- Soft Magnetic Materials (AREA)
- Heat Treatment Of Articles (AREA)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| AT81305667T ATE12527T1 (de) | 1981-01-16 | 1981-12-02 | Ferritischer, rostfreier, korrosionsbestaendiger, schweissbarer stahl mit geringem gehalt an zwischengittersubstanzen und verfahren zu seiner herstellung. |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US22556681A | 1981-01-16 | 1981-01-16 | |
| US225566 | 1981-01-16 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| EP0057316A1 EP0057316A1 (en) | 1982-08-11 |
| EP0057316B1 true EP0057316B1 (en) | 1985-04-03 |
Family
ID=22845370
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP81305667A Expired EP0057316B1 (en) | 1981-01-16 | 1981-12-02 | Low interstitial, corrosion resistant, weldable ferritic stainless steel and process for the manufacture thereof |
Country Status (10)
| Country | Link |
|---|---|
| EP (1) | EP0057316B1 (ko) |
| JP (1) | JPS57137455A (ko) |
| KR (1) | KR880001356B1 (ko) |
| AT (1) | ATE12527T1 (ko) |
| AU (1) | AU7829481A (ko) |
| BR (1) | BR8200150A (ko) |
| CA (1) | CA1184403A (ko) |
| DE (1) | DE3169748D1 (ko) |
| ES (1) | ES8305049A1 (ko) |
| MX (1) | MX156238A (ko) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6331535A (ja) * | 1986-07-23 | 1988-02-10 | Jgc Corp | 炭素析出抑止性含炭素化合物処理装置 |
| US4942922A (en) * | 1988-10-18 | 1990-07-24 | Crucible Materials Corporation | Welded corrosion-resistant ferritic stainless steel tubing having high resistance to hydrogen embrittlement and a cathodically protected heat exchanger containing the same |
| FR2644478B1 (ko) * | 1989-03-16 | 1993-10-15 | Ugine Aciers Chatillon Gueugnon | |
| JP2739531B2 (ja) * | 1991-09-17 | 1998-04-15 | 日新製鋼株式会社 | 溶接部耐食性に優れるフェライト系ステンレス鋼 |
| US5830408A (en) * | 1993-10-20 | 1998-11-03 | Sumitomo Metal Industries, Ltd. | Stainless steel for high-purity gases |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2183715A (en) * | 1938-05-21 | 1939-12-19 | Electro Metallurg Co | Corrosion resistant steel alloy |
| GB1359629A (en) * | 1971-10-26 | 1974-07-10 | Deutsche Edelstahlwerke Gmbh | Corrosion-resistant ferritic chrome steel |
| AT341561B (de) * | 1972-04-14 | 1978-02-10 | Nyby Bruk Ab | Verwendung eines stahles fur die herstellung von langzeitig mit heisswasser in beruhrung stehenden gegenstanden |
| SU515825A1 (ru) * | 1974-05-13 | 1976-05-30 | Предприятие П/Я В-2120 | Ферритна сталь |
| DE2701329C2 (de) * | 1977-01-14 | 1983-03-24 | Thyssen Edelstahlwerke AG, 4000 Düsseldorf | Korrosionsbeständiger ferritischer Chrom-Molybdän-Nickelstahl |
| US4331474A (en) * | 1980-09-24 | 1982-05-25 | Armco Inc. | Ferritic stainless steel having toughness and weldability |
-
1981
- 1981-12-02 AT AT81305667T patent/ATE12527T1/de not_active IP Right Cessation
- 1981-12-02 DE DE8181305667T patent/DE3169748D1/de not_active Expired
- 1981-12-02 EP EP81305667A patent/EP0057316B1/en not_active Expired
- 1981-12-04 AU AU78294/81A patent/AU7829481A/en not_active Abandoned
- 1981-12-08 CA CA000391706A patent/CA1184403A/en not_active Expired
- 1981-12-09 KR KR1019810004803A patent/KR880001356B1/ko active Pre-grant Review Request
- 1981-12-28 ES ES508364A patent/ES8305049A1/es not_active Expired
-
1982
- 1982-01-13 BR BR8200150A patent/BR8200150A/pt unknown
- 1982-01-14 MX MX190981A patent/MX156238A/es unknown
- 1982-01-16 JP JP57005324A patent/JPS57137455A/ja active Pending
Also Published As
| Publication number | Publication date |
|---|---|
| AU7829481A (en) | 1982-07-22 |
| DE3169748D1 (en) | 1985-05-09 |
| KR880001356B1 (ko) | 1988-07-28 |
| CA1184403A (en) | 1985-03-26 |
| ATE12527T1 (de) | 1985-04-15 |
| KR830007871A (ko) | 1983-11-07 |
| JPS57137455A (en) | 1982-08-25 |
| EP0057316A1 (en) | 1982-08-11 |
| BR8200150A (pt) | 1982-11-03 |
| ES508364A0 (es) | 1983-03-16 |
| MX156238A (es) | 1988-07-27 |
| ES8305049A1 (es) | 1983-03-16 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP3288497B2 (ja) | オーステナイトステンレス鋼 | |
| EP0220141B1 (en) | High nitrogen containing duplex stainless steel having high corrosion resistance and good structure stability | |
| JP3227468B2 (ja) | 高強度、切欠延性、析出硬化ステンレス鋼合金 | |
| JP6117372B2 (ja) | 高強度析出硬化型ステンレス鋼 | |
| GB2084187A (en) | Ferritic stainless steel | |
| CA1068132A (en) | High strength ferritic alloy | |
| CA1214667A (en) | Duplex alloy | |
| US6623569B2 (en) | Duplex stainless steels | |
| JP2023515568A (ja) | 高破壊靭性かつ高強度の析出硬化型ステンレス鋼 | |
| US4545826A (en) | Method for producing a weldable austenitic stainless steel in heavy sections | |
| EP0438992B1 (en) | Austenitic stainless steel | |
| US3278298A (en) | Chromium-nickel-aluminum steel and method | |
| US7572407B2 (en) | Martensitic stainless steel sheet and method for making the same | |
| EP0057316B1 (en) | Low interstitial, corrosion resistant, weldable ferritic stainless steel and process for the manufacture thereof | |
| US3342590A (en) | Precipitation hardenable stainless steel | |
| JPS582265B2 (ja) | フエライトゴウキン | |
| US4832765A (en) | Duplex alloy | |
| US4255497A (en) | Ferritic stainless steel | |
| EP0738784B1 (en) | High chromium martensitic steel pipe having excellent pitting resistance and method of manufacturing | |
| Machmeier et al. | Development of a strong (1650MNm− 2 tensile strength) martensitic steel having good fracture toughness | |
| US3672876A (en) | Ductile corrosion-resistant ferrous alloys containing chromium | |
| US4050928A (en) | Corrosion-resistant matrix-strengthened alloy | |
| JPS59211553A (ja) | 靭性及び高温強度の優れた高Ｃｒ鋼 | |
| US4664725A (en) | Nitrogen-containing dual phase stainless steel with improved hot workability | |
| JPS59211552A (ja) | 靭性の良好なマルテンサイト系高Ｃｒ鋼 |
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 |
|
| AK | Designated contracting states |
Designated state(s): AT BE CH DE FR GB IT LU NL SE |
|
| 17P | Request for examination filed |
Effective date: 19821223 |
|
| ITF | It: translation for a ep patent filed | ||
| GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
| AK | Designated contracting states |
Designated state(s): AT BE CH DE FR GB IT LI LU NL SE |
|
| REF | Corresponds to: |
Ref document number: 12527 Country of ref document: AT Date of ref document: 19850415 Kind code of ref document: T |
|
| REF | Corresponds to: |
Ref document number: 3169748 Country of ref document: DE Date of ref document: 19850509 |
|
| ET | Fr: translation filed | ||
| REG | Reference to a national code |
Ref country code: CH Ref legal event code: PL |
|
| PLBI | Opposition filed |
Free format text: ORIGINAL CODE: 0009260 |
|
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: LU Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 19851231 |
|
| PLBI | Opposition filed |
Free format text: ORIGINAL CODE: 0009260 |
|
| 26 | Opposition filed |
Opponent name: KRUPP STAHL AKTIENGESELLSCHAFT Effective date: 19851116 |
|
| NLR1 | Nl: opposition has been filed with the epo |
Opponent name: KRUPP STAHL AKTIENGESELLSCHAFT |
|
| 26 | Opposition filed |
Opponent name: UGINE ACIERS Effective date: 19851219 Opponent name: THYSSEN EDELSTAHLWERKE AG Effective date: 19851221 |
|
| NLR1 | Nl: opposition has been filed with the epo |
Opponent name: UGINE ACIERS Opponent name: THYSSEN EDELSTAHLWERKE AG |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: AT Payment date: 19861120 Year of fee payment: 6 |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: NL Payment date: 19871231 Year of fee payment: 7 |
|
| RDAG | Patent revoked |
Free format text: ORIGINAL CODE: 0009271 |
|
| STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: PATENT REVOKED |
|
| GBPR | Gb: patent revoked under art. 102 of the ep convention designating the uk as contracting state | ||
| 27W | Patent revoked |
Effective date: 19880512 |
|
| REG | Reference to a national code |
Ref country code: CH Ref legal event code: PL |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: FR Payment date: 19881213 Year of fee payment: 8 |
|
| NLR2 | Nl: decision of opposition | ||
| ITTA | It: last paid annual fee | ||
| BERE | Be: lapsed |
Owner name: ALLEGHENY LUDLUM STEEL CORP. Effective date: 19891231 |
|
| EUG | Se: european patent has lapsed |
Ref document number: 81305667.8 |