EP0317864A1 - Use of a chromium-containing alloy - Google Patents

Use of a chromium-containing alloy Download PDF

Info

Publication number
EP0317864A1
EP0317864A1 EP88118958A EP88118958A EP0317864A1 EP 0317864 A1 EP0317864 A1 EP 0317864A1 EP 88118958 A EP88118958 A EP 88118958A EP 88118958 A EP88118958 A EP 88118958A EP 0317864 A1 EP0317864 A1 EP 0317864A1
Authority
EP
European Patent Office
Prior art keywords
nitric acid
alloy according
weight
chromium
alloys
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
EP88118958A
Other languages
German (de)
French (fr)
Other versions
EP0317864B1 (en
Inventor
Elmar-Manfred Dr. Horn
Helmut Diekmann
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.)
Bayer AG
Original Assignee
Bayer AG
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 Bayer AG filed Critical Bayer AG
Publication of EP0317864A1 publication Critical patent/EP0317864A1/en
Application granted granted Critical
Publication of EP0317864B1 publication Critical patent/EP0317864B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

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
    • C22C38/40—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
    • C22C30/00—Alloys containing less than 50% by weight of each constituent
    • 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
    • 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

  • the present invention relates to the use of alloys with the mass fractions 35.5-69% iron, 21 -35% chrome, 10 -25% nickel and 0 - 4.5% molybdenum, as well as the usual accompanying elements, such as carbon, silicon, manganese, phosphorus, sulfur, copper, cobalt, aluminum, vanadium, titanium, tantalum and / or niobium, as a material for objects that protect against nitric acid up to a concentration of about 75% in the temperature range are stable up to 150 ° C from the melting point of nitric acid.
  • the said alloy is distinguished above all by its high chromium content, which is preferably 23-32%, particularly preferably 27-32%.
  • the nickel content is 10-25%, preferably 10-20%.
  • the Alloy can also have molybdenum contents of up to 4.5%, preferably up to 3%.
  • the alloys which can be used according to the invention can also be alloyed with manganese, for example up to 10%, preferably up to 6%, or nitrogen, for example up to 0.5%, preferably up to 0.2%.
  • the alloy element manganese which may be present does not have a negative effect on the resistance to nitric acid in the alloys to be used according to the invention.
  • the nitrogen solubility increases within the specified range with increasing chromium content.
  • the alloys have an austenitic-ferritic structure, the proportion of ferrite surface area is above 10%.
  • the alloys mentioned can be used as a material for objects which are resistant to nitric acid.
  • objects are devices of the most varied types, reactors, pipelines, pumps, pump parts, stirrers, fittings, flanges, filter baskets and welding filler material for welded connections of such devices or device parts.
  • the alloys mentioned can preferably be used as a filler metal and as cast steel for cast apparatus or apparatus parts, such as pumps.
  • the resistance of the alloys which can be used according to the invention ranges up to nitric acid concentrations of 75%. In the same way, there is a high resistance to mixed acid from sulfuric acid and nitric acid, as used, for example, for nitrating aromatic compounds.
  • the durability is also given for the temperature range from the melting point of nitric acid up to about 150 ° C, preferably up to 130 ° C. This means that resistance is given both for the nitric acid in the liquid phase and for nitric acid vapors, for example in the gas space above one corresponding temperatures of heated mixture containing nitric acid.
  • Austenitic chromium-nickel (molybdenum, copper) materials for example materials with the numbers 1.4306, 1.4335 or 2.4858, have mainly been used to handle up to about 75% nitric acids. To weld these materials together, either similarly composed or alloyed welding consumables were used. The filler materials generally lead to a fully austenitic weld metal, for example with the standard composition 25% chromium, 22% nickel, 2.2% molybdenum, 5% manganese and 0.15% nitrogen. If a delta ferrite-containing weld metal had to be used for reasons of safety against hot cracking, the formation of a coherent ferrite network had to be avoided. Such a network formation is to be expected from about 10% ferrite surface area.
  • welded weld metal of the composition (mass fractions in%) 0.022 C. 1.05 Si 1.01 Mn 0.019 P 0.012 S 29.25 Cr 12.05 Ni 0.135 N rest Fe Made with a delta ferrite content of 24 to 26% and claimed in the melted state and after additional solution treatment (1060 ° C / 15 min / water) in boiling azeotropic nitric acid, as described in Example 1. There were area-related mass loss rates of 0.10 g / (m2 .h) on average, which were practically constant over the test period. This finding applies to both the welded and solution annealed condition. In both cases, no intercrystalline attack was detectable metallographically; the material samples had only roughened according to the removal rate.
  • the weld metal was produced by melting a coated stick electrode, core wire diameter 3.25 mm.
  • connection welds were produced from 4 mm thick sheets of the stainless austenitic steels X 1 CrNi 25 21 and X 1 NiCr 31 27 with the aid of the coated stick electrode used in Example 2, core wire diameter 3.25 mm. These joint welds were stressed in boiling azeotropic nitric acid for 100 days without intermediate weighing. The removal rates are 0.07 mm / a (X 1 CrNi 25 21) and 0.05 mm / a (X 1 NiCr 31 27). The grain boundaries of the base material and weld metal were only etched.

Abstract

Alloys containing 35.5-69% by weight of iron, 21-35% by weight of chromium, 10-25% by weight of nickel and 0.4.5% by weight of molybdenum as well as the customary accompanying elements, such as carbon, silicon, manganese, phosphorus, sulphur, copper, cobalt, aluminium, vanadium, titanium, tantalum and/or niobum can be used as materials for articles which are resistant to nitric acid up to a concentration of about 75% in the temperature range from the melting point of the nitric acid to 150<o>C.

Description

Die vorliegende Erfindung betrifft die Verwendung von Legierungen mit den Massenanteilen
35,5-69 % Eisen,
21 -35 % Chrom,
10 -25 % Nickel und
0 - 4,5 % Molybdän,
sowie den üblichen Begleitelementen, wie Kohlenstoff, Silicium, Mangan, Phosphor, Schwefel, Kupfer, Kobalt, Aluminium, Vanadin, Titan, Tantal und/oder Niob, als Werkstoff für Gegenstände, die gegen Salpetersäure bis zu einer Konzentration von etwa 75 % im Temperaturbe­reich vom Schmelzpunkt der Salpetersäure bis zu 150°C beständig sind.The present invention relates to the use of alloys with the mass fractions
35.5-69% iron,
21 -35% chrome,
10 -25% nickel and
0 - 4.5% molybdenum,
as well as the usual accompanying elements, such as carbon, silicon, manganese, phosphorus, sulfur, copper, cobalt, aluminum, vanadium, titanium, tantalum and / or niobium, as a material for objects that protect against nitric acid up to a concentration of about 75% in the temperature range are stable up to 150 ° C from the melting point of nitric acid.

Die genannte Legierung ist vor allem durch ihren hohen Gehalt an Chrom ausgezeichnet, der in bevorzugter Weise 23-32 %, besonders bevorzugt 27-32 %, beträgt. Der Gehalt an Nickel beträgt 10-25 %, bevorzugt 10-20 %. Die Legierung kann weiterhin Molybdängehalte bis zu 4,5 %, bevorzugt bis zu 3 % aufweisen. Neben den oben bereits genannten Begleitelementen können die erfindungsgemäß einsetzbaren Legierungen auch mit Mangan, beispielsweise bis zu 10 %, bevorzugt bis zu 6 %, bzw. Stickstoff, bei­spielsweise bis zu 0,5 %, bevorzugt bis zu 0,2 %, le­giert sein. Das gegebenenfalls vorliegende Legierungs­element Mangan wirkt sich in den erfindungsgemäß ein­zusetzenden Legierungen nicht negativ auf die Salpeter­säurebeständigkeit aus. Die Stickstofflöslichkeit steigt im angegebenen Rahmen mit steigendem Chromgehalt.The said alloy is distinguished above all by its high chromium content, which is preferably 23-32%, particularly preferably 27-32%. The nickel content is 10-25%, preferably 10-20%. The Alloy can also have molybdenum contents of up to 4.5%, preferably up to 3%. In addition to the accompanying elements already mentioned above, the alloys which can be used according to the invention can also be alloyed with manganese, for example up to 10%, preferably up to 6%, or nitrogen, for example up to 0.5%, preferably up to 0.2%. The alloy element manganese which may be present does not have a negative effect on the resistance to nitric acid in the alloys to be used according to the invention. The nitrogen solubility increases within the specified range with increasing chromium content.

Die Legierungen besitzen ein austenitisch-ferritisches Gefüge, dessen Ferritflächenanteil oberhalb von 10 % liegt.The alloys have an austenitic-ferritic structure, the proportion of ferrite surface area is above 10%.

Die genannten Legierungen können erfindungsgemäß als Werkstoff für Gegenstände, die gegen Salpetersäure be­ständig sind, eingesetzt werden. Solche Gegenstände sind Apparate der verschiedensten Art, Reaktoren, Rohrlei­tungen, Pumpen, Pumpenteile, Rührer, Armaturen, Flan­sche, Filterkörbe sowie Schweißzusatzwerkstoff für Schweißverbindungen solcher Apparate oder Apparateteile. In bevorzugter Weise sind die genannten Legierungen einsetzbar als Schweißzusatzwerkstoff und als Stahlguß für gegossene Apparate oder Apparateteile, wie Pumpen.According to the invention, the alloys mentioned can be used as a material for objects which are resistant to nitric acid. Such objects are devices of the most varied types, reactors, pipelines, pumps, pump parts, stirrers, fittings, flanges, filter baskets and welding filler material for welded connections of such devices or device parts. The alloys mentioned can preferably be used as a filler metal and as cast steel for cast apparatus or apparatus parts, such as pumps.

Die Beständigkeit der erfindungsgemäß einsetzbaren Le­gierungen reicht bis zu Salpetersäurekonzentrationen von 75 %. In gleicher Weise ist eine hohe Beständigkeit gegen Mischsäure aus Schwefelsäure und Salpetersäure gegeben, wie sie beispielsweise zum Nitrieren aroma­tischer Verbindungen eingesetzt wird. Die Beständigkeit ist weiterhin gegeben für den Temperaturbereich vom Schmelzpunkt der Salpetersäure bis zu etwa 150° C, be­vorzugt bis zu 130° C. Das heißt, daß eine Beständigkeit gegeben ist sowohl für die Salpetersäure in flüssiger Phase als auch für Salpetersäuredämpfe, etwa im Gasraum oberhalb eines auf entsprechende Temperaturen erhitzten salpetersäurehaltigen Gemisches.The resistance of the alloys which can be used according to the invention ranges up to nitric acid concentrations of 75%. In the same way, there is a high resistance to mixed acid from sulfuric acid and nitric acid, as used, for example, for nitrating aromatic compounds. The durability is also given for the temperature range from the melting point of nitric acid up to about 150 ° C, preferably up to 130 ° C. This means that resistance is given both for the nitric acid in the liquid phase and for nitric acid vapors, for example in the gas space above one corresponding temperatures of heated mixture containing nitric acid.

Bei der erfindungsgemäßen Verwendung der oben genannten Legierungen als Schweißzusatzwerkstoff kann dieser für alle bekannten Verbindungs- und Auftragsschweißverfahren eingesetzt werden.When the above-mentioned alloys are used as welding filler material according to the invention, this can be used for all known joining and surfacing processes.

Zur Handhabung von bis zu etwa 75 %igen Salpetersäuren wurden bisher vorwiegend austenitische Chrom-Nickel-(Mo­lybdän, Kupfer)-Werkstoffe verwendet, beispielsweise Werkstoffe mit den Nummern 1.4306, 1.4335 oder 2.4858. Zum Verbindungsschweißen dieser Werkstoffe verwendete man entweder ähnlich zusammengesetzte oder überlegierte Schweißzusatzwerkstoffe. Die Zusatzwerkstoffe führen im allgemeinen zu einem vollaustenitischen Schweißgut, bei­spielsweise mit der Richtzusammensetzung 25 % Chrom, 22 % Nickel, 2,2 % Molybdän, 5 % Mangan und 0,15 % Stickstoff. Mußte aus Gründen der Heißrißsicherheit auf ein deltaferrithaltiges Schweißgut zurückgegriffen wer­den, war die Ausbildung eines zusammenhängenden Ferrit­netzwerkes zu vermeiden. Mit einer solchen Netzbildung ist ab etwa 10 % Ferritflächenanteil zu rechnen.Austenitic chromium-nickel (molybdenum, copper) materials, for example materials with the numbers 1.4306, 1.4335 or 2.4858, have mainly been used to handle up to about 75% nitric acids. To weld these materials together, either similarly composed or alloyed welding consumables were used. The filler materials generally lead to a fully austenitic weld metal, for example with the standard composition 25% chromium, 22% nickel, 2.2% molybdenum, 5% manganese and 0.15% nitrogen. If a delta ferrite-containing weld metal had to be used for reasons of safety against hot cracking, the formation of a coherent ferrite network had to be avoided. Such a network formation is to be expected from about 10% ferrite surface area.

Überraschend wurde nun gefunden, daß auch bei größeren Ferritflächenanteilen eine hohe Salpetersäurebeständig­keit dann erzielt werden kann, wenn Legierungen der hier beschriebenen Art verwendet werden.Surprisingly, it has now been found that a high nitric acid resistance can also be achieved with larger ferrite surface fractions if alloys of the type described here are used.

Beispiel 1example 1

Abgeschmolzenes Schweißgut der Zusammensetzung (Massen­anteile in %) 0,033 C 0,14 Si 1,0 Mn 0,017 P 0,010 S 24,8 Cr 12,1 Ni 0,09 N Rest Fe mit einem Deltaferritgehalt um 13,5 % wurde in siedender azeotroper Salpetersäure beansprucht. Die Prüfdauer be­trug 50 Prüfabschnitte zu je 48 h. Es stellen sich flä­chenbezogene Massenverluste von im Mittel 0,19 g/(m².h) bei einer Tiefe des interkristallinen Angriffs von max. 40 µm ein. Durch Lösungsglühen (1050°C/20 min/Wasser) ließen sich die Massenverlustraten auf 0,08 bis 0,10 g/(m².h) reduzieren; die Tiefe des Korngrenzen­angriffs lag nun bei lediglich max. 5 µm. Durch das Lösungsglühen wurde der Deltaferritanteil nicht meßbar verändert.

Figure imgb0001
Figure imgb0002
 Melted weld metal of the composition (mass fractions in%) 0.033 C. 0.14 Si 1.0 Mn 0.017 P 0.010 S 24.8 Cr 12.1 Ni 0.09 N rest Fe with a delta ferrite content of around 13.5% was used in boiling azeotropic nitric acid. The test duration was 50 test sections of 48 hours each. There are area-related mass losses of on average 0.19 g / (m².h) with a depth of the intergranular attack of max. 40 µm. Solution annealing (1050 ° C / 20 min / water) reduced the mass loss rates to 0.08 to 0.10 g / (m².h); the depth of the grain boundary attack was now only max. 5 µm. The delta ferrite content was not measurably changed by the solution annealing.
Figure imgb0001
Figure imgb0002

Beispiel 2Example 2

Analog Beispiel 1 wurde abgeschmolzenes Schweißgut der Zusammensetzung (Massenanteile in %) 0,022 C 1,05 Si 1,01 Mn 0,019 P 0,012 S 29,25 Cr 12,05 Ni 0,135 N Rest Fe mit einem Deltaferritanteil von 24 bis 26 % hergestellt und im abgeschmolzenen Zustand sowie nach zusätzlichem Lösungsglühen (1060° C/15 min/Wasser) in siedender azeo­troper Salpetersäure, wie in Beispiel 1 beschrieben, beansprucht. Es ergaben sich flächenbezogene Massen­verlustraten von im Mittel 0,10 g/(m² .h), die über die Prüfdauer hinweg praktisch konstant waren. Dieser Befund gilt sowohl für den geschweißten als auch für den lö­sungsgeglühten Zustand. In beiden Fällen war metallo­graphisch kein interkristalliner Angriff zu erkennen; die Werkstoffproben hatten sich lediglich, der Ab­tragungsrate entsprechend, angerauht. Das Schweißgut wurde durch Abschmelzen einer umhüllten Stabelektrode, Kerndrahtdurchmesser 3,25 mm, hergestellt.

Figure imgb0003
Analogous to example 1, welded weld metal of the composition (mass fractions in%) 0.022 C. 1.05 Si 1.01 Mn 0.019 P 0.012 S 29.25 Cr 12.05 Ni 0.135 N rest Fe Made with a delta ferrite content of 24 to 26% and claimed in the melted state and after additional solution treatment (1060 ° C / 15 min / water) in boiling azeotropic nitric acid, as described in Example 1. There were area-related mass loss rates of 0.10 g / (m² .h) on average, which were practically constant over the test period. This finding applies to both the welded and solution annealed condition. In both cases, no intercrystalline attack was detectable metallographically; the material samples had only roughened according to the removal rate. The weld metal was produced by melting a coated stick electrode, core wire diameter 3.25 mm.
Figure imgb0003

Beispiel 3Example 3

Aus 4 mm dicken Blechen aus den nichtrostenden austeni­schen Stählen X 1 CrNi 25 21 und X 1 NiCr 31 27 wurden mit Hilfe der im Beispiel 2 verwendeten umhüllten Stabelektrode, Kerndrahtdurchmesser 3,25 mm, Verbin­dungsschweißungen hergestellt. Diese Verbindungs­schweißungen wurden 100 Tage lang ohne Zwischenwägungen in siedender azeotroper Salpetersäure beansprucht. Die Abtragungsraten belaufen sich auf 0,07 mm/a (X 1 CrNi 25 21) bzw. 0,05 mm/a (X 1 NiCr 31 27). Die Korngrenzen von Grundwerkstoff und Schweißgut waren lediglich angeätzt.Connection welds were produced from 4 mm thick sheets of the stainless austenitic steels X 1 CrNi 25 21 and X 1 NiCr 31 27 with the aid of the coated stick electrode used in Example 2, core wire diameter 3.25 mm. These joint welds were stressed in boiling azeotropic nitric acid for 100 days without intermediate weighing. The removal rates are 0.07 mm / a (X 1 CrNi 25 21) and 0.05 mm / a (X 1 NiCr 31 27). The grain boundaries of the base material and weld metal were only etched.

Claims (6)

1. Verwendung von Legierungen mit den Massenanteilen
35,5-69 % Eisen,
21 -35 % Chrom,
10 -25 % Nickel und
0 - 4,5 % Molybdän,
sowie den üblichen Begleitelementen, wie Kohlen­stoff, Mangan, Silicium, Phosphor, Schwefel, Kup­fer, Kobalt, Aluminium, Vanadin, Titan, Tantal und/ober Niob, als Werkstoff für Gegenstände, die gegen Salpetersäure bis zu einer Konzentration von etwa 75 % im Temperaturbereich vom Schmelzpunkt der Salpetersäure bis zu 150° C beständig sind.1. Use of alloys with the mass fractions
35.5-69% iron,
21 -35% chrome,
10 -25% nickel and
0 - 4.5% molybdenum,
as well as the usual accompanying elements, such as carbon, manganese, silicon, phosphorus, sulfur, copper, cobalt, aluminum, vanadium, titanium, tantalum and / or niobium, as a material for objects that protect against nitric acid up to a concentration of about 75% in the temperature range are stable up to 150 ° C from the melting point of nitric acid. 2. Verwendung einer Legierung gemäß Anspruch 1, da­durch gekennzeichnet, daß der Chromgehalt 23-32 % beträgt.2. Use of an alloy according to claim 1, characterized in that the chromium content is 23-32%. 3. Verwendung einer Legierung gemäß Anspruch 2, da­durch gekennzeichnet, daß der Chromgehalt 27-32 % beträgt.3. Use of an alloy according to claim 2, characterized in that the chromium content is 27-32%. 4. Verwendung einer Legierung gemäß Anspruch 1 als Schweißzusatzwerkstoff und als Stahlguß für Bau­teile.4. Use of an alloy according to claim 1 as a filler metal and as a cast steel for components. 5. Verwendung einer Legierung gemäß Anspruch 1, da­durch gekennzeichnet, daß sie ein austenitisch-­ferritisches Gefüge aufweist.5. Use of an alloy according to claim 1, characterized in that it has an austenitic-ferritic structure. 6. Verwendung einer Legierung gemäß Anspruch 5, da­durch gekennzeichnet, daß der Ferritflächenanteil eines austenitisch-ferritischen Gefüges oberhalb von 10 % liegt.6. Use of an alloy according to claim 5, characterized in that the ferrite surface portion of an austenitic-ferritic structure is above 10%.
EP88118958A 1987-11-25 1988-11-14 Use of a chromium-containing alloy Expired - Lifetime EP0317864B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3739903 1987-11-25
DE19873739903 DE3739903A1 (en) 1987-11-25 1987-11-25 USE OF A CHROMIUM ALLOY

Publications (2)

Publication Number Publication Date
EP0317864A1 true EP0317864A1 (en) 1989-05-31
EP0317864B1 EP0317864B1 (en) 1992-03-04

Family

ID=6341215

Family Applications (1)

Application Number Title Priority Date Filing Date
EP88118958A Expired - Lifetime EP0317864B1 (en) 1987-11-25 1988-11-14 Use of a chromium-containing alloy

Country Status (2)

Country Link
EP (1) EP0317864B1 (en)
DE (2) DE3739903A1 (en)

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US28772A (en) * 1860-06-19 Frederic plant
US3129120A (en) * 1962-02-05 1964-04-14 United States Steel Corp Stainless steel resistant to nitric acid corrosion
US3171738A (en) * 1960-06-29 1965-03-02 Allegheny Ludlum Steel Austenitic stainless steel
GB1135906A (en) * 1966-10-21 1968-12-11 Sandvikens Jernverks Ab Improvements in or relating to alloy steel
US3486885A (en) * 1967-04-03 1969-12-30 Atomic Energy Commission Stainless steel alloy with low phosphorus content
US3645725A (en) * 1969-05-02 1972-02-29 Armco Steel Corp Austenitic steel combining strength and resistance to intergranular corrosion
US4405389A (en) * 1982-10-21 1983-09-20 Ingersoll-Rand Company Austenitic stainless steel casting alloy for corrosive applications

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA1214667A (en) * 1983-01-05 1986-12-02 Terry A. Debold Duplex alloy
JPS59150692A (en) * 1983-02-17 1984-08-28 Nippon Stainless Steel Co Ltd Welding material of ferrite-austenite two-phase stainless steel
JPS6033345A (en) * 1983-08-05 1985-02-20 Sumitomo Metal Ind Ltd Nitric acid resistant austenite stainless steel
JPS6033342A (en) * 1983-08-05 1985-02-20 Sumitomo Metal Ind Ltd Nitric acid resistant two-phase stainless steel
DE3508532A1 (en) * 1985-03-09 1986-09-18 Bayer Ag, 5090 Leverkusen USE OF A CHROME ALLOY

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US28772A (en) * 1860-06-19 Frederic plant
US3171738A (en) * 1960-06-29 1965-03-02 Allegheny Ludlum Steel Austenitic stainless steel
US3129120A (en) * 1962-02-05 1964-04-14 United States Steel Corp Stainless steel resistant to nitric acid corrosion
GB1135906A (en) * 1966-10-21 1968-12-11 Sandvikens Jernverks Ab Improvements in or relating to alloy steel
US3486885A (en) * 1967-04-03 1969-12-30 Atomic Energy Commission Stainless steel alloy with low phosphorus content
US3645725A (en) * 1969-05-02 1972-02-29 Armco Steel Corp Austenitic steel combining strength and resistance to intergranular corrosion
US4405389A (en) * 1982-10-21 1983-09-20 Ingersoll-Rand Company Austenitic stainless steel casting alloy for corrosive applications

Also Published As

Publication number Publication date
DE3739903A1 (en) 1989-06-08
EP0317864B1 (en) 1992-03-04
DE3868869D1 (en) 1992-04-09

Similar Documents

Publication Publication Date Title
DE2752083C2 (en) Austenitic, stainless steel
DE2721998C2 (en) Stainless ferritic-austenitic steel alloy
DE2718767C2 (en) Process for the production of ferritic stainless steels with improved properties in the welded state
DE3300392C2 (en)
DE3004758C2 (en) Pressure vessel with a base layer made of carbon or low-alloy steel
DE19723491C1 (en) Use of a nickel-chromium-molybdenum alloy
DE3624669C2 (en) Use of 9% chrome steel as a material for steam generators in fast breeders
EP0558915B1 (en) Austenitic nickel alloy
DE3720055A1 (en) CORROSION-RESISTANT AND WEAR-RESISTANT STEEL
DE1608180B1 (en) USING A NICKEL-CHROME STEEL ALLOY
DE3405588A1 (en) WELDING MATERIAL FROM TWO-PHASE, STAINLESS STEEL FERRITE-AUSTENITE STEEL
EP0317864B1 (en) Use of a chromium-containing alloy
EP0516955B1 (en) Corrosion resistant austenitic steel with high silicon content
AT405297B (en) DUPLEX ALLOY FOR COMPLEXLY STRESSED COMPONENTS
DE3737314C2 (en) Jacket pipe for a tubular heater made of austenitic, stainless steel
DE2634403C2 (en) Stainless alloy steel casting
DE19628350B4 (en) Use of a stainless ferritic-austenitic steel alloy
EP0256429A1 (en) Constructional steel resistant to stress corrosion cracking
DE1608180C (en) Use of a nickel-chromium steel alloy
DE3736965C2 (en)
DE19631712C2 (en) Use of an austenitic chromium-nickel-molybdenum steel alloy
DE3012957A1 (en) FERRITIC STAINLESS STEEL
EP0255106A2 (en) Process for the production of corrosion-resistant steels and castings
DE2255673A1 (en) Chrome-nickel-molybdenum nitrogen steel - for non-heat treated welded joints
DE2655696C3 (en) stole

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: 19881114

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): BE CH DE FR GB LI NL

17Q First examination report despatched

Effective date: 19900205

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): BE CH DE FR GB LI NL

GBT Gb: translation of ep patent filed (gb section 77(6)(a)/1977)
REF Corresponds to:

Ref document number: 3868869

Country of ref document: DE

Date of ref document: 19920409

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

Ref country code: DE

Payment date: 19941013

Year of fee payment: 7

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

Ref country code: FR

Payment date: 19941027

Year of fee payment: 7

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

Ref country code: GB

Payment date: 19941104

Year of fee payment: 7

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

Ref country code: CH

Payment date: 19941109

Year of fee payment: 7

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

Ref country code: BE

Payment date: 19941123

Year of fee payment: 7

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

Ref country code: NL

Payment date: 19941130

Year of fee payment: 7

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

Ref country code: GB

Effective date: 19951114

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

Ref country code: LI

Effective date: 19951130

Ref country code: CH

Effective date: 19951130

Ref country code: BE

Effective date: 19951130

BERE Be: lapsed

Owner name: BAYER A.G.

Effective date: 19951130

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

Ref country code: NL

Effective date: 19960601

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

Effective date: 19951114

REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

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

Ref country code: FR

Effective date: 19960731

NLV4 Nl: lapsed or anulled due to non-payment of the annual fee

Effective date: 19960601

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

Ref country code: DE

Effective date: 19960801

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST