EP0913491B1 - Process for producing a workpiece from a chromium alloy and its use - Google Patents
Process for producing a workpiece from a chromium alloy and its use Download PDFInfo
- Publication number
- EP0913491B1 EP0913491B1 EP98811018A EP98811018A EP0913491B1 EP 0913491 B1 EP0913491 B1 EP 0913491B1 EP 98811018 A EP98811018 A EP 98811018A EP 98811018 A EP98811018 A EP 98811018A EP 0913491 B1 EP0913491 B1 EP 0913491B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- weight
- max
- workpiece
- produced according
- mpa
- 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 - Lifetime
Links
- 238000000034 method Methods 0.000 title claims description 7
- 229910000599 Cr alloy Inorganic materials 0.000 title claims description 4
- 239000000788 chromium alloy Substances 0.000 title claims description 4
- 238000005260 corrosion Methods 0.000 claims description 27
- 230000007797 corrosion Effects 0.000 claims description 27
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 14
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 claims description 12
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 12
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims description 12
- 229910052804 chromium Inorganic materials 0.000 claims description 12
- 239000011651 chromium Substances 0.000 claims description 12
- 229910052799 carbon Inorganic materials 0.000 claims description 10
- 238000005336 cracking Methods 0.000 claims description 10
- 229910052757 nitrogen Inorganic materials 0.000 claims description 10
- 238000004519 manufacturing process Methods 0.000 claims description 8
- 229910052750 molybdenum Inorganic materials 0.000 claims description 8
- 239000000126 substance Substances 0.000 claims description 8
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 claims description 7
- 239000011733 molybdenum Substances 0.000 claims description 7
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 7
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 6
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 6
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 claims description 6
- 229910052802 copper Inorganic materials 0.000 claims description 6
- 239000010949 copper Substances 0.000 claims description 6
- 239000012535 impurity Substances 0.000 claims description 6
- 229910052742 iron Inorganic materials 0.000 claims description 6
- 229910052759 nickel Inorganic materials 0.000 claims description 6
- 229910052698 phosphorus Inorganic materials 0.000 claims description 6
- 239000011574 phosphorus Substances 0.000 claims description 6
- 229910052710 silicon Inorganic materials 0.000 claims description 6
- 239000010703 silicon Substances 0.000 claims description 6
- 238000005482 strain hardening Methods 0.000 claims description 6
- 229910000831 Steel Inorganic materials 0.000 claims description 5
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 claims description 5
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 5
- 229910052782 aluminium Inorganic materials 0.000 claims description 5
- 238000010276 construction Methods 0.000 claims description 5
- 239000010959 steel Substances 0.000 claims description 5
- 238000011089 mechanical engineering Methods 0.000 claims description 3
- 238000005553 drilling Methods 0.000 claims description 2
- 239000003921 oil Substances 0.000 claims description 2
- 239000005864 Sulphur Substances 0.000 claims 2
- 239000004411 aluminium Substances 0.000 claims 2
- 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 2
- 230000004888 barrier function Effects 0.000 claims 1
- 230000009189 diving Effects 0.000 claims 1
- 230000002787 reinforcement Effects 0.000 claims 1
- 239000011435 rock Substances 0.000 claims 1
- 239000000725 suspension Substances 0.000 claims 1
- 230000009182 swimming Effects 0.000 claims 1
- 238000004642 transportation engineering Methods 0.000 claims 1
- 229910045601 alloy Inorganic materials 0.000 description 24
- 239000000956 alloy Substances 0.000 description 24
- 239000000463 material Substances 0.000 description 20
- 229910052748 manganese Inorganic materials 0.000 description 12
- 239000011572 manganese Substances 0.000 description 12
- 230000005307 ferromagnetism Effects 0.000 description 7
- 238000005516 engineering process Methods 0.000 description 6
- 239000000203 mixture Substances 0.000 description 6
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 description 4
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 4
- 150000004820 halides Chemical class 0.000 description 4
- 238000010438 heat treatment Methods 0.000 description 3
- 229910052717 sulfur Inorganic materials 0.000 description 3
- 239000011593 sulfur Substances 0.000 description 3
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 1
- 238000005097 cold rolling Methods 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 230000005294 ferromagnetic effect Effects 0.000 description 1
- 230000005291 magnetic effect Effects 0.000 description 1
- 229910000734 martensite Inorganic materials 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 230000000704 physical effect Effects 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
Images
Classifications
-
- 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
- C21D7/10—Modifying the physical properties of iron or steel by deformation by cold working of the whole cross-section, e.g. of concrete reinforcing bars
-
- 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
Definitions
- the invention is based on a method for producing a workpiece made of a chrome alloy according to the preamble of the first claim.
- the invention also relates to the use of that produced by the process Workpiece.
- An alloy is known from EP 0 657 556 A1 with the composition: 32-37 % By weight chrome 28-36 % By weight nickel Max. 2 % By weight manganese Max. 0.5 % By weight silicon Max. 0.1 % By weight aluminum Max. 0.03 % By weight carbon Max. 0.025 % By weight phosphorus Max. 0.01 % By weight sulfur Max. 2 % By weight molybdenum Max. 1 % By weight copper 0.3 - 0.7 % By weight nitrogen Remainder iron and manufacturing-related admixtures and impurities.
- the alloy described in EP 0 657 556 A1 is manufactured by Krupp VDM sold under the name Nicrofer® 3033 - alloy 33.
- Krupp VDM, Nicrofer® 3033 - alloy 33, material sheet No. 4142, June 1995 edition describes that workpieces after 15% cold working should be subjected to heat treatment at temperatures from 1080 to 1150 ° C, preferably at 1120 ° C. To achieve optimal Corrosion properties are accelerated with after heat treatment Cool water. After the heat treatment, the workpieces have the low strengths described above.
- the invention has for its object in a method for manufacturing a workpiece made of a chrome alloy of the type mentioned Material with high strength, toughness, freedom from ferromagnetism and Freedom from susceptibility to stress corrosion cracking, both in water and in to create aqueous halide solutions.
- the workpiece is cold worked and brought to a yield strength of at least 1000 MPa (R p0.2 ⁇ 1000 MPa) by the cold working.
- the advantages of the invention can be seen, inter alia, in the fact that degrees of cold deformation (decrease in cross section due to cold deformation) of 20 percent and more, up to over 90 percent, bring about very excellent combinations of mechanical, physical and chemical properties. Yield strengths of 1000 MPa to well over 2000 MPa can still be achieved with good toughness (elongation at break of five to over ten percent). The result is a material of the highest strength that can meet the requirements of modern technology. Another advantage is the special physical and chemical properties that cannot be found with conventional materials of the same strength and corrosion resistance. The special physical properties of the material according to the invention are evident in the absence of ferromagnetism, which is a prerequisite for use as a cap ring material in turbogenerator construction. Due to its high stability of the face-centered cubic crystal lattice, the material according to the invention shows no deformation martensite even after severe cold working and thus remains free of ferromagnetism.
- the present invention has provided a material which, owing to its excellent combination of mechanical strength and toughness, as well as corrosion resistance and its resistance to stress corrosion cracking and the absence of ferromagnetism, can be used specifically in the following fields of application: energy technology, offshore technology and oil drilling technology, air, and space, civil engineering, general mechanical engineering, chemical and petrochemical industry.
- the drawing shows the yield strength R p02 , the tensile strength R m and the elongation at break A 5 depending on the degree of cold deformation.
- the particularly preferred alloy ranges had the following composition: 32-37 % By weight chrome 28-36 % By weight nickel Max. 2 % By weight manganese Max. 0.5 % By weight silicon Max. 0.1 % By weight aluminum Max. 0.03 % By weight carbon Max. 0.025 % By weight phosphorus Max. 0.01 % By weight sulfur 0.5 - 2 % By weight molybdenum 0.3 - 1 % By weight copper 0.3 - 0.7 % By weight nitrogen Remainder iron and manufacturing-related admixtures and impurities.
- the properties of the invention cold worked alloys are summarized in Table 1. Two comparison alloys are included in the table. It is about the alloys most used today worldwide for the alloy according to the invention Use as material for highly stressed generator rotor cap rings.
- the cold-formed alloy according to the invention is obviously distinguished by an unusually good combination of strength, ductility and toughness.
- the decisive superiority of the cold-formed chrome-based alloy is evident in the corrosion properties and resistance to stress corrosion cracking. It is known that the corrosion resistance of austenitic steels increases in proportion to the chromium, molybdenum and nitrogen content, corresponding to the empirical active sum% Cr + 3.3% Mo + 20% N. An effective total value of approximately 45 is achieved with the alloy according to the invention.
- the corrosion resistance is therefore at a level which is significantly higher than that of the steels used today for generator rotor cap rings with 18% Cr, 18% Mn, 0.6N or 18% Mn, 5% Cr, 0.55% C.
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Crystallography & Structural Chemistry (AREA)
- Heat Treatment Of Steel (AREA)
- Heat Treatment Of Articles (AREA)
Description
Die Erfindung geht aus von einem Verfahren zur Herstellung eines Werkstückes aus einer Chromlegierung nach dem Oberbegriff des ersten Anspruches. Die Erfindung betrifft ebenfalls die Verwendung des nach dem Verfahren hergestellten Werkstückes.The invention is based on a method for producing a workpiece made of a chrome alloy according to the preamble of the first claim. The invention also relates to the use of that produced by the process Workpiece.
In der Energietechnik, insbesondere für Kappenringe (Englisch: "Retaining Rings") im Turbogeneratorenbau, der Offshore-Technik, in der Luft- und Raumfahrt, in der Architektur, im Allgemeinen Maschinenbau, in der chemischen Industrie und in der Verkehrstechnik werden Werkstoffe verlangt, die neben sehr hoher Festigkeit, Zähigkeit und Freiheit von Ferromagnetismus auch frei sind von Anfälligkeit auf Korrosion und Spannungsrisskorrosion, sowohl in Wasser als auch in wässerigen Halogenidlösungen. Werkstoffe die alle diese Bedingungen genügend erfüllen sind jedoch bis heute unbekannt. Deshalb wird jeweils versucht, Werkstoffe für den jeweiligen Anwendungsbereich so auszuwählen, dass die wichtigsten Eigenschaften zumindest abgedeckt werden um ein Versagen des Werkstoffes zu verhindern. Dabei wird in Kauf genommen, dass bei sich ändernden Betriebsbedingungen durch zu wenig beachtete Nebeneigenschaften der Werkstoff versagen kann.In energy technology, especially for cap rings (English: "Retaining Rings") in turbogenerator construction, offshore technology, in aerospace, in Architecture, in general mechanical engineering, in the chemical industry and in the Traffic engineering requires materials that, in addition to very high strength, toughness and freedom from ferromagnetism are also free from susceptibility to corrosion and stress corrosion cracking, both in water and in water Halide solutions. Materials that meet all of these conditions sufficiently are still unknown to this day. That is why we try to find materials for select the respective area of application so that the most important properties at least be covered to prevent material failure. It is accepted that with changing operating conditions fail due to insufficient attention to the secondary properties of the material can.
Bei Kappenringen im Turbogeneratorenbau werden beispielsweise Stähle mit der Zusammensetzung 18%Cr, 18%Mn, 0.6N bzw. 18%Mn, 5%Cr, 0.55%C verwendet. Diese Werkstoffe weisen zwar die gewünschte hohe Festigkeit, Zähigkeit und Freiheit von Ferromagnetismus auf, ihre Korrosions- und Spannungsrisskorrosionseigenschaften können jedoch bei besonders korrosionsfördernden Betriebs- und Umweltbedingungen zum Problem werden.In the case of cap rings in turbogenerator construction, steels are used with the Composition 18% Cr, 18% Mn, 0.6N or 18% Mn, 5% Cr, 0.55% C used. These materials have the desired high strength, toughness and Freedom from ferromagnetism, their corrosion and stress corrosion cracking properties However, in the case of particularly corrosive and environmental conditions become a problem.
Aus der EP 0 657 556 A1 ist eine Legierung bekannt mit der Zusammensetzung:
Diese in der EP 0 657 556 A1 beschriebenen Legierungen weisen zwar eine gewünschte
hohe Beständigkeit gegen allgemeine Korrosion auf, erreichen aber lediglich
Streckgrenzen ("Dehngrenzen") von maximal ungefähr 500 MPa und Zugfestigkeiten
von ungefähr 850 MPa. Dies genügt den oben gestellten Forderungen
an höchste Festigkeiten, die die vorgängig beschriebenen Legierungen erfüllen,
jedoch nicht.These alloys described in
Die in der EP 0 657 556 A1 beschriebenen Legierung wird von der Firma Krupp
VDM unter dem Namen Nicrofer® 3033 - alloy 33 vertrieben. Im zugehörigen
Werkstoffblatt, Krupp VDM, Nicrofer® 3033 - alloy 33, Werkstoffblatt Nr. 4142,
Ausgabe Juni 1995, wird beschrieben, dass Werkstücke nach 15% Kaltverformung
einer Wärmebehandlung unterworfen werden sollten, die bei Temperaturen
von 1080 bis 1150°C, vorzugsweise bei 1120°C erfolgen soll. Zur Erzielung optimaler
Korrosionseigenschaften ist nach der Wärmebehandlung beschleunigt mit
Wasser abzukühlen. Nach der Wärmebehandlung weisen die Werkstücke die
oben beschriebenen, geringen Festigkeiten auf.The alloy described in
Der Erfindung liegt die Aufgabe zugrunde, bei einem Verfahren zur Herstellung eines Werkstückes aus einer Chromlegierung der eingangs genannten Art einen Werkstoff mit hoher Festigkeit, Zähigkeit, Freiheit von Ferromagnetismus und Freiheit von Anfälligkeit auf Spannungsrisskorrosion, sowohl in Wasser als auch in wässerigen Halogenidlösungen zu schaffen.The invention has for its object in a method for manufacturing a workpiece made of a chrome alloy of the type mentioned Material with high strength, toughness, freedom from ferromagnetism and Freedom from susceptibility to stress corrosion cracking, both in water and in to create aqueous halide solutions.
Erfindungsgemäss wird dies durch die Merkmale des ersten Anspruches erreicht. Kern der Erfindung ist es also, dass das Werkstück kaltverformt und durch die Kaltverformung auf eine Streckgrenze von mindestens 1000 MPa (Rp0.2 ≥ 1000 MPa) gebracht wird.According to the invention, this is achieved by the features of the first claim. The essence of the invention is therefore that the workpiece is cold worked and brought to a yield strength of at least 1000 MPa (R p0.2 ≥ 1000 MPa) by the cold working.
Die Vorteile der Erfindung sind unter anderem darin zu sehen, dass Kaltverformungsgrade
(Querschnittsabnahme durch Kaltverformung) von 20 Prozent und
mehr, bis zu über 90 Prozent, ganz hervorragende Kombinationen von mechanischen,
physikalischen und chemischen Eigenschaften bewirken. Es können so
Streckgrenzen von 1000 MPa bis deutlich über 2000 MPa bei immer noch guter
Zähigkeit (Bruchdehnung von fünf bis über zehn Prozent) erzielt werden. Es entsteht
so ein Werkstoff höchster Festigkeit, der die Anforderungen der modernen
Techniken zu erfüllen vermag.
Ein weiterer Vorteil sind die besonderen physikalischen und chemischen Eigenschaften,
die bei herkömmlichen Werkstoffen gleicher Festigkeit und gleicher Korrosionsbeständigkeit
nicht zu finden sind. Die besonderen physikalischen Eigenschaften
des erfindungsgemässen Werkstoffs zeigen sich wesentlich in der Abwesenheit
von Ferromagnetismus, welche Voraussetzung für die Anwendung als
Kappenringwerkstoff im Turbogeneratorenbau ist. Der erfindungsgemässe Werkstoff
zeigt durch seine hohe Stabilität des kubisch-flächenzentrierten Kristallgitters
auch nach starker Kaltverformung keinen Verformungsmartensit und bleibt somit
frei von Ferromagnetismus.The advantages of the invention can be seen, inter alia, in the fact that degrees of cold deformation (decrease in cross section due to cold deformation) of 20 percent and more, up to over 90 percent, bring about very excellent combinations of mechanical, physical and chemical properties. Yield strengths of 1000 MPa to well over 2000 MPa can still be achieved with good toughness (elongation at break of five to over ten percent). The result is a material of the highest strength that can meet the requirements of modern technology.
Another advantage is the special physical and chemical properties that cannot be found with conventional materials of the same strength and corrosion resistance. The special physical properties of the material according to the invention are evident in the absence of ferromagnetism, which is a prerequisite for use as a cap ring material in turbogenerator construction. Due to its high stability of the face-centered cubic crystal lattice, the material according to the invention shows no deformation martensite even after severe cold working and thus remains free of ferromagnetism.
Die besonderen chemischen Eigenschaften des erfindungsgemäss stark kaltverformten
Werkstoffes zeigen sich im Widerstand gegen Spannungsrisskorrosion in
Wasser und wässrigen Halogenidlösungen. Andere kaltverformte, nicht ferromagnetische
korrosionsbeständige Werkstoffe, bis in die Klasse der "Superaustenite"
hinauf, insbesondere aber alle bisher in der Technik üblichen Stähle für Kappenringe
zeigen sich im hochfesten, kaltverformten Zustand stets anfällig auf Spannungsrisskorrosion,
zumindest in warmen, wässrigen Chloridlösungen. Mit dem
erfindungsgemässen hohen Kaltverformungsgrad von 20 Prozent und mehr, angewandt
auf die genannte Chromlegierung, ist hier nun erstmals ein Werkstoff geschaffen
worden, der selbst bei höchster Festigkeit, Korrosionsbeständigkeit sowie
zugleich Abwesenheit von Ferromagnetismus völlig beständig gegen Spannungsrisskorrosion
in wässrigen Halogenidlösungen ist.
Die vorliegende Erfindung hat mit dem genannten Verfahren einen Werkstoff bereitgestellt,
der aufgrund seiner hervorragenden Kombination von mechanischer
Festigkeit und Zähigkeit sowie Korrosionsbeständigkeit und seines Widerstandes
gegen Spannungsrisskorrosion sowie Abwesenheit von Ferromagnetismus spezifisch
in folgenden Anwendungsgebieten eingesetzt werden kann: Energietechnik,
Offshoretechnik und Ölbohrtechnik, Luft-, und Raumfahrt, Hoch- und Tiefbau, Allgemeiner
Maschinenbau, Chemische und Petrochemische Industrie.The special chemical properties of the material which is strongly cold-formed according to the invention are evident in the resistance to stress corrosion cracking in water and aqueous halide solutions. Other cold-formed, non-ferromagnetic, corrosion-resistant materials up to the class of "superaustenite", but especially all the hitherto conventional steel for cap rings are always susceptible to stress corrosion cracking in the high-strength, cold-formed state, at least in warm, aqueous chloride solutions. With the high degree of cold deformation according to the invention of 20 percent and more, applied to the above-mentioned chromium alloy, a material has now been created for the first time that is completely resistant to stress corrosion cracking in aqueous halide solutions, even with the highest strength, corrosion resistance and absence of ferromagnetism.
With the method mentioned, the present invention has provided a material which, owing to its excellent combination of mechanical strength and toughness, as well as corrosion resistance and its resistance to stress corrosion cracking and the absence of ferromagnetism, can be used specifically in the following fields of application: energy technology, offshore technology and oil drilling technology, air, and space, civil engineering, general mechanical engineering, chemical and petrochemical industry.
Weitere vorteilhafte Ausgestaltungen und Verwendungen der Erfindung ergeben sich aus den Unteransprüchen.Further advantageous configurations and uses of the invention result itself from the subclaims.
In der Zeichnung ist die Streckgrenze Rp02, die Zugfestigkeit Rm und die Bruchdehnung A5 abhängig vom Kaltverformungsgrad dargestellt. The drawing shows the yield strength R p02 , the tensile strength R m and the elongation at break A 5 depending on the degree of cold deformation.
Werkstücke aus Chrombasis-Legierungen der nachfolgenden Zusammensetzung
wurden kaltverformt.
Die besonders bevorzugten Legierungsbereiche wiesen folgende Zusammensetzung
auf:
Diese Werkstücke wurden dabei verschiedenen Kaltverformungsgraden unterworfen und die so erhaltenen Werkstücke untersucht. In der einzigen Figur ist die Streckgrenze Rp02, die Zugfestigkeit Rm und die Bruchdehnung A5 dem Kaltverformungsgrad gegenübergestellt. Wie aus der Figur ersichtlich ist, konnten bei Kaltverformungsgraden über 25% Streckgrenzen von über 1000 MPa erreicht werden. Die kaltverformten Werkstücke wurden verschiedenen Korrosions- und Spannungsrisskorrosionversuchen unterworfen, wobei mindestens die gleich guten Werte wie bei unverformten Werkstücken erzielt wurden.These workpieces were subjected to various degrees of cold deformation and the workpieces thus obtained were examined. In the single figure, the yield point R p02 , the tensile strength R m and the elongation at break A 5 are compared to the degree of cold deformation. As can be seen from the figure, it was possible to achieve yield strengths of over 1000 MPa at degrees of cold deformation above 25%. The cold-formed workpieces were subjected to various corrosion and stress corrosion tests, with at least the same good values being achieved as for undeformed workpieces.
Eine Chrombasis-Legierung der folgenden chemischen Zusammensetzung
Eine lösungsgeglühte Walzplatte der gleichen chemischen Zusammensetzung wie in Beispiel 1 wurde, ausgehend vom lösungsgeglühten Zustand, durch Kaltwalzen verformt. Der Umformgrad betrug 25% und 35%. Die Eigenschaften der erfindungsgemäss kaltverformten Legierung sind in der Tabelle 1 zusammengefasst. Zwei Vergleichslegierungen sind mit in die Tabelle aufgenommen. Es handelt sich dabei um die heute weltweit am meisten verwendeten Legierungen für den erfindungsgemässen Einsatz als Werkstoff für hochbeanspruchte Generatorrotor-Kappenringe.A solution annealed plate with the same chemical composition as in Example 1, starting from the solution-annealed condition, was carried out by cold rolling deformed. The degree of deformation was 25% and 35%. The properties of the invention cold worked alloys are summarized in Table 1. Two comparison alloys are included in the table. It is about the alloys most used today worldwide for the alloy according to the invention Use as material for highly stressed generator rotor cap rings.
Offensichtlich zeichnet sich die erfindungsgemäss kaltverformte Legierung aus
durch eine ungewöhnlich gute Kombination von Festigkeit, Duktilität und Zähigkeit.
Die entscheidende Überlegenheit der kaltverformten Chrombasis-Legierung
offenbart sich aber bei den Korrosionseigenschaften und dem Widerstand gegen
Spannungsrisskorrosion. Es ist bekannt, dass der Korrosionswiderstand austenitischer
Stähle proportional zum Chrom-, Molybdän- und Stickstoffgehalt steigt, entsprechend
der empirischen Wirksumme %Cr+3.3%Mo+20%N. Mit der erfindungsgemässen
Legierung wird ein Wirksummenwert von etwa 45 erzielt. Der Korrosionswiderstand
liegt damit auf einem Niveau, das deutlich höher liegt als das der
heute für Generatorrotor-Kappenringe eingesetzte Stähle mit 18%Cr, 18%Mn,
0.6N bzw. 18%Mn, 5%Cr, 0.55%C. Dies zeigt sich experimentell in der kritischen
Spaltkorrosionstemperatur, die für die erfindungsgemäss kaltverformte Legierung
bei 20°C liegt, während sie für die Legierungen mit 18%Cr, 18%Mn, 0.6%N bzw.
18%Mn, 5%Cr, 0.55%C unter -3°C liegt.
Besonders hervorzuheben ist jedoch der Widerstand gegen Spannungsrisskorrosion der erfindungsgemäss kaltverformten Legierung. Dazu wurden bruchmechanische Tests mit vorermüdeten DCB-Proben in Wasser und 22%iger NaCI-Lösung durchgeführt. Nach einer Prüfdauer von 2000 h hat sich kein Risswachstum gezeigt. Damit kann als mögliche Obergrenze für ein Risswachstum ein Wert von < 10-11 m/s angegeben werden. Die Vergleichswerkstoffe zweigen demgegenüber ein Risswachstum von ca. 10-9 m/s (18%Cr, 18%Mn, 0.6%N) bzw. 10-8 m/s (18%Mn, 5%Cr, 0.55%C).Of particular note, however, is the resistance to stress corrosion cracking of the cold-formed alloy according to the invention. For this purpose, mechanical fracture tests were carried out with pre-tired DCB samples in water and 22% NaCI solution. After a test period of 2000 h, no crack growth was shown. A value of <10 -11 m / s can thus be given as a possible upper limit for crack growth. The comparison materials, on the other hand, branch a crack growth of approx. 10 -9 m / s (18% Cr, 18% Mn, 0.6% N) or 10 -8 m / s (18% Mn, 5% Cr, 0.55% C).
Selbstverständlich ist die Erfindung nicht auf die gezeigten und beschriebenen Ausführungsbeispiele beschränkt.Of course, the invention is not limited to that shown and described Embodiments limited.
Claims (10)
- Process for producing a workpiece from a chromium alloy, consisting of:
32-37 % by weight chromium, 28-36 % by weight nickel, max. 2 % by weight manganese, max. 0.5 % by weight silicon, max. 0.1 % by weight aluminium, max. 0.03 % by weight carbon, max. 0.025 % by weight phosphorus, max. 0.01 % by weight sulphur, max. 2 % by weight molybdenum, max. 1 % by weight copper, 0.3-0.7 % by weight nitrogen, - Process for producing a workpiece from a chromium alloy, consisting of:
32-37 % by weight chromium, 28-36 % by weight nickel, max. 2 % by weight manganese, max. 0.5 % by weight silicon, max. 0.1 % by weight aluminium, max. 0.03 % by weight carbon, max. 0.025 % by weight phosphorus, max. 0.01 % by weight sulphur, 0.5-2 % by weight molybdenum, 0.3-1 % by weight copper, 0.3-0.7 % by weight nitrogen, - Process for producing a workpiece according to Claim 1 or 2, characterized in that the degree of cold deformation is at least 20%.
- Use of the workpiece produced according to one of Claims 1 to 3 for generator/rotor retaining rings.
- Use of the workpiece produced according to one of Claims 1 to 3 in offshore and oil drilling engineering for valves, pipelines, connecting elements and drill stems.
- Use of the workpiece produced according to one of Claims 1 to 3 in aeronautical and aerospatial engineering for load-bearing components and for connecting elements, in particular screws, bolts and rivets.
- Use of the workpiece produced according to one of Claims 1 to 3 in the building and construction industry for connecting elements, such as nails, rivets, screws, dowels, and for stay cables, rock bolts, attachment elements on facades, facade ties, tunnels, bridges, roofs, including roof suspensions for swimming pools, and for tensioning cables, turnbuckles, anchor plates, hinges, crash barrier anchorages, load-bearing structures, reinforcements and for supporting elements in steel construction.
- Use of the workpiece produced according to one of Claims 1 to 3 in general mechanical engineering and in the chemical and petrochemical industry where stress corrosion cracking media are applied to high-strength components which are under mechanical stresses.
- Use of the workpiece produced according to one of Claims 1 to 3 for components in transport engineering on water and on land, in amphibious vehicles, in load-bearing and guide systems which have to simultaneously withstand mechanical loads and aggressive environments.
- Use of the workpiece produced according to one of Claims 1 to 3 in sport and leisure equipment, including shipbuilding and diving equipment.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19748205A DE19748205A1 (en) | 1997-10-31 | 1997-10-31 | Process for producing a workpiece from a chrome alloy and its use |
| DE19748205 | 1997-10-31 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| EP0913491A1 EP0913491A1 (en) | 1999-05-06 |
| EP0913491B1 true EP0913491B1 (en) | 2001-11-28 |
Family
ID=7847257
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP98811018A Expired - Lifetime EP0913491B1 (en) | 1997-10-31 | 1998-10-13 | Process for producing a workpiece from a chromium alloy and its use |
Country Status (6)
| Country | Link |
|---|---|
| US (2) | US6406572B1 (en) |
| EP (1) | EP0913491B1 (en) |
| JP (1) | JPH11246922A (en) |
| CN (1) | CN1093885C (en) |
| DE (2) | DE19748205A1 (en) |
| PL (1) | PL329400A1 (en) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| AT408889B (en) | 2000-06-30 | 2002-03-25 | Schoeller Bleckmann Oilfield T | CORROSION-RESISTANT MATERIAL |
| RU2514899C1 (en) * | 2013-01-30 | 2014-05-10 | Анатолий Матвеевич Адаскин | Thermal treatment of heatproof and refractory alloy "х65нвфт" |
| RU2515145C1 (en) * | 2013-05-30 | 2014-05-10 | Анатолий Матвеевич Адаскин | Thermal treatment of heatproof and refractory alloy "х65нвфт" |
| EP3269924A1 (en) | 2016-07-14 | 2018-01-17 | Siemens Aktiengesellschaft | Rotating shaft and method for producing a rotating shaft |
| EP3844311A1 (en) * | 2018-08-29 | 2021-07-07 | Chemetics Inc. | Austenitic stainless alloy with superior corrosion resistance |
| US20220411906A1 (en) * | 2019-10-10 | 2022-12-29 | Nippon Steel Corporation | Alloy material and oil-well seamless pipe |
| CN115323234B (en) * | 2022-08-09 | 2023-08-01 | 东睦新材料集团股份有限公司 | Preparation method of nonmagnetic low-expansion chromium-based alloy material |
Family Cites Families (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4424083A (en) * | 1980-11-21 | 1984-01-03 | Exxon Research And Engineering Co. | Carburization resistance of austenitic stainless steel tubes |
| US4400209A (en) * | 1981-06-10 | 1983-08-23 | Sumitomo Metal Industries, Ltd. | Alloy for making high strength deep well casing and tubing having improved resistance to stress-corrosion cracking |
| US4400210A (en) * | 1981-06-10 | 1983-08-23 | Sumitomo Metal Industries, Ltd. | Alloy for making high strength deep well casing and tubing having improved resistance to stress-corrosion cracking |
| US4421571A (en) * | 1981-07-03 | 1983-12-20 | Sumitomo Metal Industries, Ltd. | Process for making high strength deep well casing and tubing having improved resistance to stress-corrosion cracking |
| JPS6141746A (en) * | 1984-08-01 | 1986-02-28 | Nippon Steel Corp | High strength and high corrosion resistance heat resisting steel superior in hot workability |
| US4761190A (en) * | 1985-12-11 | 1988-08-02 | Inco Alloys International, Inc. | Method of manufacture of a heat resistant alloy useful in heat recuperator applications and product |
| JPS62180037A (en) | 1986-02-03 | 1987-08-07 | Daido Steel Co Ltd | Austenitic alloy excellent in stress corrosion cracking resistance |
| US5378427A (en) * | 1991-03-13 | 1995-01-03 | Sumitomo Metal Industries, Ltd. | Corrosion-resistant alloy heat transfer tubes for heat-recovery boilers |
| DE4342188C2 (en) * | 1993-12-10 | 1998-06-04 | Bayer Ag | Austenitic alloys and their uses |
| JPH08120392A (en) * | 1994-10-21 | 1996-05-14 | Sumitomo Metal Ind Ltd | Austenitic corrosion resistant alloy for high efficiency rubbish power generating boiler superheater tube |
-
1997
- 1997-10-31 DE DE19748205A patent/DE19748205A1/en not_active Withdrawn
-
1998
- 1998-10-13 EP EP98811018A patent/EP0913491B1/en not_active Expired - Lifetime
- 1998-10-13 DE DE59802224T patent/DE59802224D1/en not_active Expired - Fee Related
- 1998-10-26 US US09/178,579 patent/US6406572B1/en not_active Expired - Fee Related
- 1998-10-28 PL PL98329400A patent/PL329400A1/en unknown
- 1998-10-29 JP JP10308559A patent/JPH11246922A/en active Pending
- 1998-10-30 CN CN98121428A patent/CN1093885C/en not_active Expired - Fee Related
-
2002
- 2002-03-21 US US10/101,703 patent/US6616779B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| CN1221802A (en) | 1999-07-07 |
| EP0913491A1 (en) | 1999-05-06 |
| PL329400A1 (en) | 1999-05-10 |
| US6616779B2 (en) | 2003-09-09 |
| US6406572B1 (en) | 2002-06-18 |
| US20020141897A1 (en) | 2002-10-03 |
| DE19748205A1 (en) | 1999-05-06 |
| JPH11246922A (en) | 1999-09-14 |
| DE59802224D1 (en) | 2002-01-10 |
| CN1093885C (en) | 2002-11-06 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| DE3221833C3 (en) | Alloy, in particular for the production of heavy-duty piping for deep holes or the like | |
| DE3221857C2 (en) | Iron alloy with increased resistance to stress corrosion cracking | |
| DE2423193C2 (en) | Use of an austenitic stainless steel | |
| DE3223457C2 (en) | ||
| DE68928336T3 (en) | Process for the production of structural steels with high fire resistance and low yield strength ratio and structural steel produced thereby | |
| DE102010026808B4 (en) | Corrosion-resistant austenitic phosphorous-alloyed steel casting with TRIP or TWIP properties and its use | |
| DE60124227T2 (en) | DUPLEX STAINLESS STEEL | |
| DE1558519A1 (en) | Steel with a maximum of 0.08 percent carbon | |
| EP2557185A1 (en) | Armature en acier profilée et laminée à chaud pour pièces en béton armé dotées d'une résistance au feu améliorée et son procédé de fabrication | |
| DE4233269A1 (en) | HIGH-STRENGTH SPRING STEEL | |
| DE1458470B2 (en) | Use of a heat-treated, ductile, high-strength steel alloy with a martensitic or bainitic structure for the production of components for aerospace engineering | |
| DE19607828C2 (en) | Process for producing an austenitic Cv-Mn steel | |
| EP0913491B1 (en) | Process for producing a workpiece from a chromium alloy and its use | |
| EP2414552B1 (en) | Ball pins made of bainitic steels for passenger car and light commercial vehicle | |
| DE3113844A1 (en) | "FERRITE-FREE, EXHAUST-RETARDABLE STAINLESS STEEL" | |
| EP2732060B1 (en) | Hardening steel for lifting, tensioning and / or load securing devices and fasteners, component and method for producing | |
| DE69838879T2 (en) | MARTENSITIC STAINLESS STEEL WITH HIGH CORROSION RESISTANCE | |
| DE2755537A1 (en) | AUSTENITIC STAINLESS STEEL | |
| DE3407305A1 (en) | USE OF A CORROSION-RESISTANT AUSTENITIC ALLOY FOR MECHANICALLY STRESSED, WELDABLE COMPONENTS | |
| DE3344775C1 (en) | Tendons for building structures | |
| EP1474538B1 (en) | Use of a steel alloy as a material for pipes for producing gas cylinders, or as a material for producing moulded elements in light-gauge steel construction | |
| DE102019103502A1 (en) | Method of manufacturing seamless steel pipe, seamless steel pipe, and pipe product | |
| WO2022049282A1 (en) | Hot-rolled flat steel product and method for producing a hot-rolled flat steel product | |
| DE3935965C1 (en) | ||
| DE19902665A1 (en) | Low carbon special steel for producing lightweight, high strength and corrosion resistant vehicle body and chassis components contains chromium and nickel |
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 |
Kind code of ref document: A1 Designated state(s): DE FR |
|
| AX | Request for extension of the european patent |
Free format text: AL;LT;LV;MK;RO;SI |
|
| 17P | Request for examination filed |
Effective date: 19991008 |
|
| AKX | Designation fees paid |
Free format text: DE FR |
|
| GRAG | Despatch of communication of intention to grant |
Free format text: ORIGINAL CODE: EPIDOS AGRA |
|
| 17Q | First examination report despatched |
Effective date: 20001122 |
|
| GRAG | Despatch of communication of intention to grant |
Free format text: ORIGINAL CODE: EPIDOS AGRA |
|
| GRAH | Despatch of communication of intention to grant a patent |
Free format text: ORIGINAL CODE: EPIDOS IGRA |
|
| GRAH | Despatch of communication of intention to grant a patent |
Free format text: ORIGINAL CODE: EPIDOS IGRA |
|
| GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
| AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): DE FR |
|
| RAP2 | Party data changed (patent owner data changed or rights of a patent transferred) |
Owner name: ALSTOM |
|
| REF | Corresponds to: |
Ref document number: 59802224 Country of ref document: DE Date of ref document: 20020110 |
|
| 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 |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: FR Payment date: 20021009 Year of fee payment: 5 |
|
| 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: 20031010 Year of fee payment: 6 |
|
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: FR Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20040630 |
|
| 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: DE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20050503 |