EP2728028B1 - Edelstahllegierung ohne Nickel - Google Patents

Edelstahllegierung ohne Nickel Download PDF

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EP2728028B1
EP2728028B1 EP12191101.0A EP12191101A EP2728028B1 EP 2728028 B1 EP2728028 B1 EP 2728028B1 EP 12191101 A EP12191101 A EP 12191101A EP 2728028 B1 EP2728028 B1 EP 2728028B1
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Prior art keywords
maximum value
valeur
minimum value
value
nickel
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German (de)
French (fr)
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EP2728028A1 (en
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Jean-François DIONNE
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Swatch Group Research and Development SA
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Swatch Group Research and Development SA
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Priority to EP12191101.0A priority Critical patent/EP2728028B1/en
Application filed by Swatch Group Research and Development SA filed Critical Swatch Group Research and Development SA
Priority to EP13785379.2A priority patent/EP2914759B1/en
Priority to US14/425,455 priority patent/US20150225820A1/en
Priority to PCT/EP2013/071770 priority patent/WO2014067795A1/en
Priority to RU2015120760A priority patent/RU2625363C2/en
Priority to JP2015533640A priority patent/JP5976945B2/en
Priority to CN201380057112.4A priority patent/CN104769145B/en
Priority to TW102138458A priority patent/TWI586816B/en
Publication of EP2728028A1 publication Critical patent/EP2728028A1/en
Priority to HK15112788.4A priority patent/HK1211992A1/en
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    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/002Ferrous alloys, e.g. steel alloys containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/18Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/38Ferrous alloys, e.g. steel alloys containing chromium with more than 1.5% by weight of manganese
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C30/00Alloys containing less than 50% by weight of each constituent
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C30/00Alloys containing less than 50% by weight of each constituent
    • C22C30/02Alloys containing less than 50% by weight of each constituent containing copper
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/001Ferrous alloys, e.g. steel alloys containing N
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/004Very low carbon steels, i.e. having a carbon content of less than 0,01%
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/005Ferrous alloys, e.g. steel alloys containing rare earths, i.e. Sc, Y, Lanthanides
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/02Ferrous alloys, e.g. steel alloys containing silicon
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/04Ferrous alloys, e.g. steel alloys containing manganese
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/18Ferrous alloys, e.g. steel alloys containing chromium
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/18Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/20Ferrous alloys, e.g. steel alloys containing chromium with copper
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/18Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/22Ferrous alloys, e.g. steel alloys containing chromium with molybdenum or tungsten
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/18Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/24Ferrous alloys, e.g. steel alloys containing chromium with vanadium
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/18Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/26Ferrous alloys, e.g. steel alloys containing chromium with niobium or tantalum
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/18Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/28Ferrous alloys, e.g. steel alloys containing chromium with titanium or zirconium
    • GPHYSICS
    • G04HOROLOGY
    • G04BMECHANICALLY-DRIVEN CLOCKS OR WATCHES; MECHANICAL PARTS OF CLOCKS OR WATCHES IN GENERAL; TIME PIECES USING THE POSITION OF THE SUN, MOON OR STARS
    • G04B37/00Cases
    • G04B37/22Materials or processes of manufacturing pocket watch or wrist watch cases
    • GPHYSICS
    • G04HOROLOGY
    • G04GELECTRONIC TIME-PIECES
    • G04G17/00Structural details; Housings
    • G04G17/02Component assemblies
    • GPHYSICS
    • G04HOROLOGY
    • G04GELECTRONIC TIME-PIECES
    • G04G17/00Structural details; Housings
    • G04G17/08Housings

Definitions

  • the invention relates to a stainless steel alloy having a base of iron and chromium.
  • the invention also relates to a watch component made of such an alloy.
  • the invention relates to the fields of watchmaking, jewelery, and jewelery, in particular for structures: watch cases, squares, turntables, bracelets, rings, earrings and others.
  • Stainless steels are commonly used in the fields of watchmaking, jewelery, and jewelery, especially for structures: watch cases, casebacks, turntables, bracelets, and others.
  • Nickel is, however, a basic component of most common stainless steels because it improves mechanical properties and ductility, malleability and resilience. By cons nickel is harmful in the field of friction surfaces. Nickel improves the properties of the passive layer, and integrates with the surface layer of oxide.
  • alloy X2CrNiMo17-12 EN (or 316L AISI) comprises between 10.5 and 13% of nickel. Nickel is a metal whose cost is growing continuously, and which, in 2012, is close to 20'000 USD per ton, which increases the cost of alloys containing it.
  • Nickel-free stainless steel alloys are known which are ferritic steels with a cubic centered structure. However, these ferritic steels are not hardenable by heat treatment, but only by hardening. Their structure is not very fine, and this family of alloys is not very suitable for polishing.
  • Austenitic steels of face-centered cubic structure, generally have very good forming properties, which is particularly advantageous for watchmaker or jeweler-type components. They have a very high chemical resistance. They are also non-magnetic because of their face-centered cubic structure. They are also the most suitable for welding. But conventional austenitic stainless steels still contain from 3.5 to 32% of nickel, and more commonly from 8.0 to 15.0% of nickel. Indeed, nickel is a gammagene element which makes it possible to obtain the austenitic structure, and in particular to obtain sheets capable of forming deformations. Some documents, such as FR 2,534,931 on behalf of CABOT CORPORATION go so far as to say that nickel must be present to favor an austenitic structure in the alloy.
  • the gamma loop of the iron-chromium system specific to stainless steels defines an austenitic domain, even with a low or zero nickel content, but the loop is of very limited magnitude compared to that of alloys containing nickel. in higher proportion. In addition, this austenitic domain exists at temperatures much higher than ambient. The effect of the gammagenic alloy elements is twofold since it also makes it possible to widen the austenitic loop in chemical composition (relative to chromium) and to widen the temperature range on which this structure is stable.
  • Austeno-ferritic steels also called duplex, are weak magnetic, and generally comprise between 3.5% and 8% nickel.
  • the nickel-free stainless steels are mainly ferritic steels
  • the advantages of the austenitic steels, which are generally cataloged as nickel steels, should be available.
  • gammagens such as nickel, manganese or nitrogen are generally used (these are called super-austenitic steels for the last two mentioned), which increase the range of stability of austenite. Theoretically it would therefore be possible to use a super-austenitic steel with manganese or nitrogen in place of nickel.
  • the patent EP 1 025 273 B1 on behalf of SIMA describes such a nickel-free austenitic stainless steel, comprising 15 to 24% manganese, 15 to 20% chromium, 2.5 to 4% molybdenum, 0.6 to 0.85% d nitrogen, 0.1 to 0.5% vanadium, less than 0.5% copper, less than 0.5% cobalt, less than 0.5% for total niobium and tantalum, less than 0.06% of carbon, other elements each limited to 0.020% by weight, the balance being iron, and the compositions of certain metals being limited to each other by means of a system of equations and inequalities, which regulate the contents of chromium, molybdenum, nitrogen, vanadium, niobium, and manganese.
  • the invention also relates to a watch or jewelery component made of such an alloy.
  • the invention proposes to produce stainless steels without nickel, which have properties similar to those of austenitic stainless steels with nickel.
  • nickel-free alloy will be referred to below as an alloy comprising less than 0.5% by weight of nickel.
  • the alloy comprises, in addition to a base consisting of iron and chromium, at least one filler metal selected from a first group consisting of copper, ruthenium, rhodium, palladium and rhenium. , osmium, iridium, platinum, and gold.
  • the alloy comprises, in addition to a base consisting of iron, carbon and chromium, at least one filler metal chosen from a subset of the first set consisting of ruthenium, rhodium, palladium, rhenium, osmium, iridium, and platinum.
  • these metals are part of PGM (platinum group metals) or platinoids, that is to say that they are characterized by common and unusual properties for metals.
  • PGM platinum group metals
  • platinoids that is to say that they are characterized by common and unusual properties for metals.
  • These PGM group metals are also more soluble in iron than copper and gold.
  • a suitable (mass) composition is 18% chromium, 35% palladium, and 46 to 47% iron. Like all stainless steel, this alloy can contain up to 0.03% carbon.
  • its mass composition is 18% chromium, 35% palladium, 0% to 0.03% carbon, and the iron supplement. More particularly, its mass composition is 18% chromium, 35% palladium, and 46.97 to 47% iron, and 0 to 0.03% carbon.
  • the figure 2 is a Schaeffler diagram, which has on the abscissa an equivalent chromium, and on the ordinate a nickel equivalent, both in percentage by mass.
  • This Schaeffler diagram delimits the ferritic, martensitic and austenitic domains, the latter limited by the curve corresponding to the zero ferrite content.
  • So-called stainless steels are, according to current standards, those containing more than 10.5% of chromium.
  • the curves C1 and C2 delimit the possible presence of austenite A: above C1 and C2 we have austenite A, underneath there is none.
  • the curve C3 delimits the possible presence of ferrite F: below C3 there is ferrite F, above there is none.
  • the curve C4 delimits the possible presence of martensite M: below C4 there is martensite M, above there is none.
  • the composition must be such that one is both above the C3 and C4 curves, so as to have only austenite A.
  • a first variant of the invention consists in incorporating into the alloy, in the limit of 0.5% by weight of the total, at least one carburigenic element taken from a second group consisting of tungsten, vanadium, niobium and zirconium. , and titanium, replacing an equivalent mass of iron in the alloy.
  • This incorporation of one or more carburigenic elements has the effect of forcing the precipitation of specific carbides less harmful to the corrosion resistance than chromium carbides.
  • the invention also relates to a watch or jewelery component made of such an alloy.

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  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
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Description

Domaine de l'inventionField of the invention

L'invention concerne un alliage d'acier inoxydable comportant une base constituée de fer et de chrome.The invention relates to a stainless steel alloy having a base of iron and chromium.

L'invention concerne encore un composant d'horlogerie réalisé en un tel alliage.The invention also relates to a watch component made of such an alloy.

L'invention concerne les domaines de l'horlogerie, de la bijouterie, et de la joaillerie, en particulier pour les structures : boîtes de montres, carrures, platines, bracelets, bagues, boucles d'oreilles et autres.The invention relates to the fields of watchmaking, jewelery, and jewelery, in particular for structures: watch cases, squares, turntables, bracelets, rings, earrings and others.

Arrière-plan de l'inventionBackground of the invention

Les aciers inoxydables sont couramment utilisés dans les domaines de l'horlogerie, de la bijouterie, et de la joaillerie, en particulier pour les structures : boîtes de montres, carrures, platines, bracelets, et autres.Stainless steels are commonly used in the fields of watchmaking, jewelery, and jewelery, especially for structures: watch cases, casebacks, turntables, bracelets, and others.

Les composants à usage externe, destinés à être en contact avec la peau de l'utilisateur, doivent obéir à certaines contraintes, en particulier en raison des effets allergènes de certains métaux, notamment le nickel. Malgré les qualités de protection et d'éclat du nickel une fois poli, on s'attache de plus en plus à mettre sur le marché des alliages comportant peu voire pas de nickel.The components for external use, intended to be in contact with the skin of the user, must obey certain constraints, in particular because of the allergenic effects of certain metals, especially nickel. Despite the protective and polished qualities of nickel once polished, there is an increasing focus on placing on the market alloys with little or no nickel.

Le nickel est toutefois un composant de base de la plupart des aciers inoxydables usuels, car il améliore les propriétés mécaniques et la ductilité, la malléabilité et la résilience. Par contre le nickel est néfaste dans le domaine des surfaces de frottement. Le nickel améliore les propriétés de la couche passive, et s'intègre à la couche superficielle d'oxyde. En particulier l'alliage X2CrNiMo17-12 EN (ou 316L AISI) comporte entre 10,5 et 13% de nickel. Le nickel est un métal dont le coût est en croissance continue, et qui, en 2012, est voisin de 20'000 USD par tonne, ce qui renchérit le coût des alliages qui en contiennent.Nickel is, however, a basic component of most common stainless steels because it improves mechanical properties and ductility, malleability and resilience. By cons nickel is harmful in the field of friction surfaces. Nickel improves the properties of the passive layer, and integrates with the surface layer of oxide. In particular alloy X2CrNiMo17-12 EN (or 316L AISI) comprises between 10.5 and 13% of nickel. Nickel is a metal whose cost is growing continuously, and which, in 2012, is close to 20'000 USD per ton, which increases the cost of alloys containing it.

On connaît des alliages d'acier inoxydable sans nickel qui sont des aciers ferritiques, de structure cubique centrée. Toutefois ces aciers ferritiques ne sont pas durcissables par traitement thermique, mais seulement par écrouissage. Leur structure est peu fine, et cette famille d'alliages est peu apte au polissage.Nickel-free stainless steel alloys are known which are ferritic steels with a cubic centered structure. However, these ferritic steels are not hardenable by heat treatment, but only by hardening. Their structure is not very fine, and this family of alloys is not very suitable for polishing.

Le document EP 0 964 071 A1 au nom de ASULAB SA décrit l'application d'un tel acier inoxydable ferritique sans nickel à une pièce extérieure d'habillage pour montre, cet alliage comportant au moins 0,4% en poids d'azote, et au plus 0,5% en poids de nickel, entre 10 et 35 % en masse pour le total de chrome et de molybdène, et entre 5 et 20% en masse de manganèse.The document EP 0 964 071 A1 in the name of ASULAB SA describes the application of such a nickel-free ferritic stainless steel to an outer piece of watch covering, this alloy comprising at least 0.4% by weight of nitrogen, and at most 0.5% by weight of nickel, between 10 and 35% by weight for the total chromium and molybdenum, and between 5 and 20% by weight of manganese.

On connaît encore d'autres alliages d'acier inoxydable sans nickel qui sont des aciers martensitiques, qui sont durcissables par traitement thermique, ils sont en revanche difficiles à usiner, particulièrement les nuances de type « maraging » qui comportent des précipités de composants durcissant, et ne peuvent être envisagés pour les applications horlogères.Other nickel-free stainless steel alloys are known that are martensitic steels, which are hardenable by heat treatment, but are difficult on the other hand. to be machined, particularly the "maraging" grades which comprise precipitates of hardening components, and can not be envisaged for horological applications.

Le brevet EP 0 629 714 B1 au nom de UGINE-SAVOIE IMPHY décrit un acier inoxydable martensitique à usinabilité améliorée, avec un taux de nickel non nul, mais compris entre 2 et 6%, un taux de chrome assez bas compris entre 11% et 19%, et une composition prévoyant de nombreux additifs, et favorable à la formation de certaines inclusions dans la matrice, améliorant ainsi l'usinabilité par fragilisation localisée des copeaux. Mais on voit que le taux de nickel, quoique bas, reste trop élevé pour l'application.The patent EP 0 629 714 B1 in the name of UGINE-SAVOIE IMPHY describes a martensitic stainless steel with improved machinability, with a non-zero nickel content, but between 2 and 6%, a fairly low chromium content of between 11% and 19%, and a predictive composition many additives, and favorable to the formation of certain inclusions in the matrix, thus improving machinability by localized weakening of the chips. But we see that the nickel rate, although low, remains too high for the application.

Les aciers austénitiques, de structure cubique faces centrées, ont généralement de très bonnes propriétés de formage, ce qui est particulièrement intéressant pour des composants de type horloger ou bijoutier. Ils ont une résistance chimique très élevée. Ils sont aussi amagnétiques en raison de leur structure cubique faces centrées. Ce sont aussi les plus aptes au soudage. Mais les aciers inoxydables austénitiques usuels comportent toujours de 3,5 à 32% de nickel, et plus couramment de 8,0 à 15,0 % de nickel. En effet, le nickel est un élément gammagène qui permet l'obtention de la structure austénitique, et d'obtenir notamment des tôles aptes aux déformations de mise en forme. Certains documents, comme FR 2 534 931 au nom de CABOT CORPORATION vont jusqu'à affirmer que le nickel doit être présent pour favoriser une structure austénitique dans l'alliage.Austenitic steels, of face-centered cubic structure, generally have very good forming properties, which is particularly advantageous for watchmaker or jeweler-type components. They have a very high chemical resistance. They are also non-magnetic because of their face-centered cubic structure. They are also the most suitable for welding. But conventional austenitic stainless steels still contain from 3.5 to 32% of nickel, and more commonly from 8.0 to 15.0% of nickel. Indeed, nickel is a gammagene element which makes it possible to obtain the austenitic structure, and in particular to obtain sheets capable of forming deformations. Some documents, such as FR 2,534,931 on behalf of CABOT CORPORATION go so far as to say that nickel must be present to favor an austenitic structure in the alloy.

Dans la théorie, la boucle gamma du système fer-chrome propre aux aciers inoxydables, définit un domaine austénitique, même avec un taux de nickel bas ou nul, mais la boucle est d'ampleur très restreinte par rapport à celle des alliages comportant du nickel en proportion supérieure. De plus, ce domaine austénitique existe à des températures beaucoup plus élevées que l'ambiante. L'effet des éléments d'alliages gammagènes est double puisqu'il permet également d'élargir la boucle austénitique en composition chimique (par rapport au chrome) et d'élargir la gamme de température sur laquelle cette structure est stable.In theory, the gamma loop of the iron-chromium system specific to stainless steels defines an austenitic domain, even with a low or zero nickel content, but the loop is of very limited magnitude compared to that of alloys containing nickel. in higher proportion. In addition, this austenitic domain exists at temperatures much higher than ambient. The effect of the gammagenic alloy elements is twofold since it also makes it possible to widen the austenitic loop in chemical composition (relative to chromium) and to widen the temperature range on which this structure is stable.

Les aciers austéno-ferritiques, encore dits duplex, sont quant à eux faiblement magnétiques, et comportent généralement entre 3,5% et 8% de nickel.Austeno-ferritic steels, also called duplex, are weak magnetic, and generally comprise between 3.5% and 8% nickel.

En somme, si, dans l'acception générale, les aciers inoxydables sans nickel sont principalement des aciers ferritiques, il faudrait pouvoir disposer des avantages des aciers austénitiques, qui sont généralement catalogués comme aciers au nickel.In sum, if, in the general sense, the nickel-free stainless steels are mainly ferritic steels, the advantages of the austenitic steels, which are generally cataloged as nickel steels, should be available.

Pour l'obtention d'un acier inoxydable austénitique, on utilise généralement des éléments gammagènes tels que le nickel, le manganèse ou l'azote (on parle alors d'aciers super-austénitiques pour les deux derniers mentionnés), qui augmentent la plage de stabilité de l'austénite. Théoriquement il serait donc possible d'utiliser un acier super-austénitique avec manganèse ou azote en lieu et place du nickel.In order to obtain austenitic stainless steel, gammagens such as nickel, manganese or nitrogen are generally used (these are called super-austenitic steels for the last two mentioned), which increase the range of stability of austenite. Theoretically it would therefore be possible to use a super-austenitic steel with manganese or nitrogen in place of nickel.

Le brevet EP 1 025 273 B1 au nom de SIMA décrit un tel acier inoxydable austénitique sans nickel, comportant de 15 à 24% de manganèse, de 15 à 20% de chrome, de 2,5 à 4% de molybdène, de 0,6 à 0,85% d'azote, de 0,1 à 0,5% de vanadium, moins de 0,5% de cuivre, moins de 0,5% de cobalt, moins de 0,5% pour le total de niobium et de tantale, moins de 0,06% de carbone, d'autres éléments chacun limité à 0,020% en masse, le reste étant constitué de fer, et les compositions de certains métaux étant limitées les unes par rapport aux autres par le biais d'un système d'équations et d'inégalités, qui encadrent les teneurs de chrome, de molybdène, d'azote, de vanadium, de niobium, et de manganèse.The patent EP 1 025 273 B1 on behalf of SIMA describes such a nickel-free austenitic stainless steel, comprising 15 to 24% manganese, 15 to 20% chromium, 2.5 to 4% molybdenum, 0.6 to 0.85% d nitrogen, 0.1 to 0.5% vanadium, less than 0.5% copper, less than 0.5% cobalt, less than 0.5% for total niobium and tantalum, less than 0.06% of carbon, other elements each limited to 0.020% by weight, the balance being iron, and the compositions of certain metals being limited to each other by means of a system of equations and inequalities, which regulate the contents of chromium, molybdenum, nitrogen, vanadium, niobium, and manganese.

Mais, si ces alliages super-austénitiques ont des propriétés mécaniques élevées, leur mise en forme est très difficile, notamment l'usinage est difficile, le matriçage n'est pas possible, et leur utilisation est de ce fait malcommode.But, if these super-austenitic alloys have high mechanical properties, their shaping is very difficult, especially the machining is difficult, the stamping is not possible, and their use is therefore inconvenient.

Des alliages inoxydables austénitiques sont connus des documents :

  • EP 1 783 240 A1 DAIDO STEEL CO LTD notamment utilisable en bijouterie ou joaillerie et à teneur élevée en azote ;
  • EP 1 025 273 B1 METALLURGIE AVANCEE SIMA sans nickel pour applications biomédicales;
  • EP 1 626 101 A1 DAIDO STEEL CO LTD à teneur élevée en azote ;
  • EP 0 896 072 A1 USINOR UGINE à très faible teneur en nickel;
  • US 2009/060 775 A1 LIU ADVANCED INT MULTITECH à teneur moyenne d'azote;
  • DE 197 16 795 A1 KRUPP à haute résistance et résistant à la corrosion ;
  • US 3 904 401 A MERTZ CARPENTER TECHNOLOGY CO résistant à la corrosion.
Austenitic stainless alloys are known from the documents:
  • EP 1 783 240 A1 DAIDO STEEL CO LTD particularly usable in jewelery and high nitrogen content;
  • EP 1 025 273 B1 METALLURGY ADVANCED SIMA nickel free for biomedical applications;
  • EP 1 626 101 A1 DAIDO STEEL CO LTD with a high nitrogen content;
  • EP 0 896 072 A1 USINOR UGINE with very low nickel content;
  • US 2009/060775 A1 LIU ADVANCED INT MULTITECH with medium nitrogen content;
  • DE 197 16 795 A1 KRUPP high strength and corrosion resistant;
  • US 3,904,401A MERTZ CARPENTER TECHNOLOGY CO resistant to corrosion.

Résumé de l'inventionSummary of the invention

A cet effet, l'invention concerne un alliage d'acier inoxydable sur une base constituée de fer et de chrome, caractérisé en ce qu'il comporte moins de 0,5% en masse de nickel, et est arrangé selon une structure austénitique cubique à faces centrées, et qu'il consiste, en valeurs en masse, en :

  • chrome : valeur mini 16%, valeur maxi 20 % ;
  • au moins un métal d'apport, la valeur du total dudit au moins un métal d'apport ou desdits métaux d'apport étant comprise entre : valeur mini 30%, valeur maxi 40%, ledit au moins un métal d'apport étant choisi parmi un premier ensemble constitué du cuivre, du ruthénium, du rhodium, du palladium, du rhénium, de l'osmium, de l'iridium, du platine, et de l'or :
    • la valeur du cuivre étant comprise entre : valeur mini 0%, valeur maxi 2 % ;
    • la valeur de l'or étant comprise entre : valeur mini 0%, valeur maxi 2 % ;
  • carbone : valeur mini 0%, valeur maxi 0,03 % ;
  • molybdène : valeur mini 0%, valeur maxi 2 % ;
  • manganèse : valeur mini 0%, valeur maxi 2 % ;
  • silicium : valeur mini 0%, valeur maxi 1 % ;
  • azote: valeur mini 0%, valeur maxi 0,1% ;
  • dans la limite de 0,5% en masse du total, au moins un élément carburigène pris parmi un deuxième ensemble constitué du tungstène, du vanadium, du niobium, du zirconium, et du titane, en remplacement d'une masse équivalent de fer dans l'alliage ;
  • fer et impuretés inévitables: le complément à 100 %.
For this purpose, the invention relates to a stainless steel alloy on a base consisting of iron and chromium, characterized in that it comprises less than 0.5% by weight of nickel, and is arranged in a cubic austenitic structure. with centered faces, and that it consists, in mass values, in:
  • chrome: min. value 16%, max. value 20%;
  • at least one filler metal, the value of the total of said at least one filler metal or said filler metals being between: minimum value 30%, maximum value 40%, said at least one filler metal being chosen among a first set consisting of copper, ruthenium, rhodium, palladium, rhenium, osmium, iridium, platinum, and gold:
    • the copper value being between: minimum value 0%, maximum value 2%;
    • the value of the gold being between: minimum value 0%, maximum value 2%;
  • carbon: minimum value 0%, maximum value 0.03%;
  • molybdenum: minimum value 0%, maximum value 2%;
  • manganese: minimum value 0%, maximum value 2%;
  • silicon: minimum value 0%, maximum value 1%;
  • nitrogen: minimum value 0%, maximum value 0.1%;
  • in the limit of 0.5% by mass of the total, at least one carburigenic element taken from a second group consisting of tungsten, vanadium, niobium, zirconium and titanium, replacing an equivalent mass of iron in the alloy;
  • iron and unavoidable impurities: the complement to 100%.

L'invention concerne encore un composant d'horlogerie ou de joaillerie réalisé en un tel alliage.The invention also relates to a watch or jewelery component made of such an alloy.

Description sommaire des dessinsBrief description of the drawings

D'autres caractéristiques et avantages de l'invention apparaîtront à la lecture de la description détaillée qui va suivre, en référence aux dessins annexés, où :

  • la figure 1 représente, de façon schématisée, la boucle gamma d'un système fer-chrome, en fonction du taux de nickel dans l'alliage ;
  • la figure 2 représente, de façon schématisée, un diagramme de Schaeffler, avec en abscisse un chrome équivalent, et en ordonnée un nickel équivalent. Ce diagramme délimite les domaines ferritique, martensitique et austénitique, ce dernier limité par la courbe correspondant au taux nul de ferrite.
Other features and advantages of the invention will appear on reading the detailed description which follows, with reference to the appended drawings, in which:
  • the figure 1 represents schematically the gamma loop of an iron-chromium system, as a function of the nickel content in the alloy;
  • the figure 2 schematically represents a Schaeffler diagram, with an equivalent chromium on the abscissa and an equivalent nickel on the ordinate. This diagram delimits the ferritic, martensitic and austenitic domains, the latter limited by the curve corresponding to the zero ferrite content.

Description détaillée des modes de réalisation préférésDetailed Description of the Preferred Embodiments

L'invention se propose de produire des aciers inoxydables sans nickel, qui possèdent des propriétés analogues à celles des aciers inoxydables austénitiques avec nickel.The invention proposes to produce stainless steels without nickel, which have properties similar to those of austenitic stainless steels with nickel.

On appellera ci-après « alliage sans nickel » un alliage comportant moins de 0,5% en masse de nickel.The term "nickel-free alloy" will be referred to below as an alloy comprising less than 0.5% by weight of nickel.

Il s'agit donc de rechercher la fabrication d'alliages, qui, comme les super-austénitiques, comportent des éléments de substitution au nickel, mais qui durcissent moins l'acier que le couple manganèse-azote.It is therefore a question of looking for the production of alloys, which, like the super-austenitics, contain elements of substitution for nickel, but which harden the steel less than the manganese-nitrogen pair.

Ces éléments de substitution doivent être solubles dans le fer, de façon à permettre la construction d'une structure austénitique cubique à faces centrées. Selon l'invention, l'alliage comporte, en complément d'une base constituée de fer et de chrome, au moins un métal d'apport choisi parmi un premier ensemble constitué du cuivre, du ruthénium, du rhodium, du palladium, du rhénium, de l'osmium, de l'iridium, du platine, et de l'or.These substitution elements must be soluble in iron, so as to allow the construction of a cubic austenitic structure with centered faces. According to the invention, the alloy comprises, in addition to a base consisting of iron and chromium, at least one filler metal selected from a first group consisting of copper, ruthenium, rhodium, palladium and rhenium. , osmium, iridium, platinum, and gold.

Dans une application préférée, l'alliage comporte, en complément d'une base constituée de fer, de carbone et de chrome, au moins un métal d'apport choisi parmi un sous-ensemble du premier ensemble constitué du ruthénium, du rhodium, du palladium, du rhénium, de l'osmium, de l'iridium, et du platine. En effet, ces métaux font partie du groupe dit PGM (platinum group metals) ou platinoïdes, c'est-à-dire qu'ils sont caractérisés par des propriétés communes et inhabituelles pour les métaux. Ces métaux du groupe PGM sont également plus solubles dans le fer que le cuivre et l'or.In a preferred application, the alloy comprises, in addition to a base consisting of iron, carbon and chromium, at least one filler metal chosen from a subset of the first set consisting of ruthenium, rhodium, palladium, rhenium, osmium, iridium, and platinum. Indeed, these metals are part of PGM (platinum group metals) or platinoids, that is to say that they are characterized by common and unusual properties for metals. These PGM group metals are also more soluble in iron than copper and gold.

Le choix du palladium comme métal d'apport permet, plus particulièrement, d'atteindre les propriétés recherchées.The choice of palladium as filler metal allows, more particularly, to achieve the desired properties.

Une composition (en masse) convenable est de 18 % de chrome, de 35 % de palladium, et de 46 à 47 % de fer. Comme tout acier inoxydable, cet alliage peut contenir jusqu'à 0,03% de carbone.A suitable (mass) composition is 18% chromium, 35% palladium, and 46 to 47% iron. Like all stainless steel, this alloy can contain up to 0.03% carbon.

De façon préférée, sa composition en masse est de 18 % de chrome, de 35 % de palladium, de 0% à 0,03% de carbone, et le complément en fer. Plus particulièrement, sa composition en masse est de 18 % de chrome, de 35 % de palladium, et de 46,97 à 47 % de fer, et de 0 à 0,03% de carbone.Preferably, its mass composition is 18% chromium, 35% palladium, 0% to 0.03% carbon, and the iron supplement. More particularly, its mass composition is 18% chromium, 35% palladium, and 46.97 to 47% iron, and 0 to 0.03% carbon.

La figure 2 est un diagramme de Schaeffler, qui comporte en abscisse un chrome équivalent, et en ordonnée un nickel équivalent, tous deux en pourcentage en masse.The figure 2 is a Schaeffler diagram, which has on the abscissa an equivalent chromium, and on the ordinate a nickel equivalent, both in percentage by mass.

Le chrome équivalent Créq répond ici à la définition suivante : Créq = Cr + Mo + 1,5 Si .

Figure imgb0001
The equivalent chromium Créq corresponds here to the following definition: CREQ = Cr + MB + 1.5 Yes .
Figure imgb0001

Ce modèle est voisin du modèle de Schaeffler ou celui de Delong : Créq = Cr + Mo + 1,5 Si + 0,5 Nb ,

Figure imgb0002
ici simplifié pour le cas d'un alliage sans niobium.This model is similar to the Schaeffler or Delong model: CREQ = Cr + MB + 1.5 Yes + 0.5 Nb ,
Figure imgb0002
here simplified for the case of an alloy without niobium.

Le point important est la détermination du taux de métal d'apport, en remplacement du nickel qui est proscrit. La notion de nickel équivalent qualifie la proportion en masse du métal d'apport, ou des métaux d'apport s'il y en a plusieurs.The important point is the determination of the filler metal content, replacing the nickel that is outlawed. The notion of equivalent nickel qualifies the proportion by weight of the filler metal, or filler metals if there are several.

Dans le cas particulier de l'emploi du palladium pour remplacer le nickel, le nickel équivalent Niéq répond à la définition suivante : Niéq = Ni + 30 C + N + 0,5 Co + Mn + Cu + 0,3 Pd .

Figure imgb0003
In the particular case of the use of palladium to replace nickel, nickel equivalent Niéq meets the following definition: Nieq = Or + 30 VS + NOT + 0.5 Co + mn + Cu + 0.3 Pd .
Figure imgb0003

Ce modèle est adapté à la présence de palladium, et dérive des modèles connus de Schaeffler (pour un alliage base manganèse): Niéq = Ni + 30 C + 0,5 Mn ,

Figure imgb0004
et plus précisément de Delong (pour un alliage base manganèse et azote): Niéq = Ni + 30 C + N + 0,5 Mn .
Figure imgb0005
This model is adapted to the presence of palladium, and derives from known Schaeffler models (for a manganese base alloy): Nieq = Or + 30 VS + 0.5 mn ,
Figure imgb0004
and more precisely Delong (for a manganese base alloy and nitrogen): Nieq = Or + 30 VS + NOT + 0.5 mn .
Figure imgb0005

Dans une généralisation à l'ensemble capable de métaux d'apport, la formule de nickel équivalent peut encore s'écrire : Niéq = Ni + 30 C + N + 0,5 Co + Mn + Cu + 0,3 Pd + Ru + Rh + Re + Os + Ir + Pt + Au ,

Figure imgb0006
ou, de préférence dans le cas où le métal d'apport est choisi parmi le premier ensemble : Niéq = Ni + 30 C + N + 0,5 Co + Mn + Cu + 0,3 Pd + Ru + Rh + Re + Os + Ir + Pt .
Figure imgb0007
In a generalization to the set capable of filler metals, the equivalent nickel formula can still be written: Nieq = Or + 30 VS + NOT + 0.5 Co + mn + Cu + 0.3 Pd + Ru + Rh + Re + Bone + Ir + Pt + At ,
Figure imgb0006
or, preferably in the case where the filler metal is selected from the first set: Nieq = Or + 30 VS + NOT + 0.5 Co + mn + Cu + 0.3 Pd + Ru + Rh + Re + Bone + Ir + Pt .
Figure imgb0007

Ce diagramme de Schaeffler délimite les domaines ferritique, martensitique et austénitique, ce dernier limité par la courbe correspondant au taux nul de ferrite.This Schaeffler diagram delimits the ferritic, martensitic and austenitic domains, the latter limited by the curve corresponding to the zero ferrite content.

Les aciers dits inoxydables sont, selon les normes en vigueur, ceux qui contiennent plus de 10,5% de chrome.So-called stainless steels are, according to current standards, those containing more than 10.5% of chromium.

Les courbes C1 et C2 délimitent la présence possible d'austénite A : au-dessus de C1 et de C2 on a de l'austénite A, en-dessous il n'y en a pas.The curves C1 and C2 delimit the possible presence of austenite A: above C1 and C2 we have austenite A, underneath there is none.

La courbe C3 délimite la présence possible de ferrite F : en-dessous de C3 il y a de la ferrite F, au-dessus il n'y en a pas.The curve C3 delimits the possible presence of ferrite F: below C3 there is ferrite F, above there is none.

La courbe C4 délimite la présence possible de martensite M : en-dessous de C4 il y a de la martensite M, au-dessus il n'y en a pas.The curve C4 delimits the possible presence of martensite M: below C4 there is martensite M, above there is none.

Pour bénéficier au mieux des propriétés de l'austénite, la composition doit être telle que l'on soit à la fois au-dessus des courbes C3 et C4, de façon à n'avoir que de l'austénite A.To best benefit from the properties of austenite, the composition must be such that one is both above the C3 and C4 curves, so as to have only austenite A.

Pour bénéficier des propriétés propres aux aciers inoxydables, il faut respecter le taux minimal de chrome figuré par la courbe C5, et le domaine est alors celui situé à droite de la courbe C5. Le domaine D1 hachuré sur la figure 2 obéit à ces deux conditions, et assure les propriétés attendues. Le point P correspondant à l'exemple cité plus haut est situé dans ce domaine D1.In order to benefit from the properties specific to stainless steels, it is necessary to respect the minimum chromium content represented by the curve C5, and the domain is then that located to the right of the curve C5. The field D1 hatched on the figure 2 obeys these two conditions, and ensures the expected properties. The point P corresponding to the example mentioned above is located in this domain D1.

Selon une approximation, les courbes sont des droites, d'équations :

  • C1 : Niéq = 5 / 6 Créq 8 + 21
    Figure imgb0008
  • C2 : Niéq = 13 / 16 Créq 8 + 13
    Figure imgb0009
  • C3 : Niéq = 13 / 9 Créq 8 2
    Figure imgb0010
  • C4 : Niéq = 7 / 16 Créq 8 3
    Figure imgb0011
According to an approximation, curves are straight lines of equations:
  • C1: Nieq = - 5 / 6 CREQ - 8 + 21
    Figure imgb0008
  • C2: Nieq = - 13 / 16 CREQ - 8 + 13
    Figure imgb0009
  • C3: Nieq = 13 / 9 CREQ - 8 - 2
    Figure imgb0010
  • C4: Nieq = 7 / 16 CREQ - 8 - 3
    Figure imgb0011

Le domaine D1 obéit aux trois conditions suivantes : Niéq 13 / 9 Créq 8 2

Figure imgb0012
Niéq 7 / 16 Créq 8 3
Figure imgb0013
Créq 10,5
Figure imgb0014
Domain D1 obeys the following three conditions: Nieq 13 / 9 CREQ - 8 - 2
Figure imgb0012
Nieq 7 / 16 CREQ - 8 - 3
Figure imgb0013
CREQ 10.5
Figure imgb0014

Bien sûr, on peut tolérer la présence d'un peu de ferrite ou de martensite avec l'austénite, et le domaine réel d'application peut être un peu plus large que le domaine D1, et en particulier pour abaisser le plus possible le niveau du nickel équivalent, en raison du coût souvent très élevé des métaux choisis en substitution au nickel ; rappelons par exemple que, en 2012 le coût du palladium est d'environ la moitié de celui de l'or, et compris entre le quart et la moitié de celui du platine.Of course, we can tolerate the presence of a little ferrite or martensite with austenite, and the real area of application can be a little wider than the D1 domain, and in particular to lower the level as much as possible. equivalent nickel, because of the often very high cost of metals chosen as substitutes for nickel; remember that in 2012 the cost of palladium is about half that of gold, and between one quarter and one half that of platinum.

Le domaine rectangulaire D2, défini par les deux inégalités suivantes : 16 Créq 23,5

Figure imgb0015
12 Niéq 22,
Figure imgb0016
donne un bon exemple de valeurs admissibles (en masse) dans le cas d'utilisation du palladium comme métal d'apport principal, selon la revendication 1:

  • palladium : valeur mini 30%, valeur maxi 40 %
  • chrome : valeur mini 16%, valeur maxi 20 %
  • molybdène : valeur mini 0%, valeur maxi 2 %
    • manganèse : valeur mini 0%, valeur maxi 2 %
  • cuivre : valeur mini 0%, valeur maxi 2 %
  • or : valeur mini 0%, valeur maxi 2 %
  • silicium : valeur mini 0%, valeur maxi 1 %
  • azote: valeur mini 0%, valeur maxi 0,1%
  • carbone : valeur mini 0%, valeur maxi 0,03 %
  • fer: le complément à 100 %.
The rectangular domain D2, defined by the following two inequalities: 16 CREQ 23.5
Figure imgb0015
12 Nieq 22
Figure imgb0016
gives a good example of permissible values (in mass) in the case of using palladium as the main filler, according to claim 1:
  • palladium: minimum value 30%, maximum value 40%
  • chrome: minimum value 16%, maximum value 20%
  • molybdenum: minimum value 0%, maximum value 2%
    • manganese: minimum value 0%, maximum value 2%
  • copper: minimum value 0%, maximum value 2%
  • gold: minimum value 0%, maximum value 2%
  • silicon: minimum value 0%, maximum value 1%
  • nitrogen: minimum value 0%, maximum value 0.1%
  • carbon: minimum value 0%, maximum value 0.03%
  • iron: the 100% supplement.

Dans la généralisation à au moins un métal d'apport pris parmi le premier ensemble ou son sous-ensemble limité aux PGM, la composition en masse selon la revendication 1 devient :

  • total du ou des métaux d'apport du premier ensemble ou de son sous-ensemble des PGM : valeur mini 30%, valeur maxi 40 %
  • chrome : valeur mini 16%, valeur maxi 20 %
  • molybdène : valeur mini 0%, valeur maxi 2 %
  • manganèse : valeur mini 0%, valeur maxi 2 %
  • cuivre : valeur mini 0%, valeur maxi 2 %
  • or : valeur mini 0%, valeur maxi 2 %
  • silicium : valeur mini 0%, valeur maxi 1 %
  • azote: valeur mini 0%, valeur maxi 0,1%
  • carbone : valeur mini 0%, valeur maxi 0,03 %
  • fer: le complément à 100 %.
In the generalization to at least one filler metal taken from the first set or its subset limited to PGM, the mass composition according to claim 1 becomes:
  • total filler metal (s) of the first set or its subset of PGMs: minimum value 30%, maximum value 40%
  • chrome: minimum value 16%, maximum value 20%
  • molybdenum: minimum value 0%, maximum value 2%
  • manganese: minimum value 0%, maximum value 2%
  • copper: minimum value 0%, maximum value 2%
  • gold: minimum value 0%, maximum value 2%
  • silicon: minimum value 0%, maximum value 1%
  • nitrogen: minimum value 0%, maximum value 0.1%
  • carbon: minimum value 0%, maximum value 0.03%
  • iron: the 100% supplement.

Une première variante de l'invention consiste à incorporer dans l'alliage, dans la limite de 0,5% en masse du total, au moins un élément carburigène pris parmi un deuxième ensemble constitué du tungstène, du vanadium, du niobium, du zirconium, et du titane, en remplacement d'une masse équivalent de fer dans l'alliage.A first variant of the invention consists in incorporating into the alloy, in the limit of 0.5% by weight of the total, at least one carburigenic element taken from a second group consisting of tungsten, vanadium, niobium and zirconium. , and titanium, replacing an equivalent mass of iron in the alloy.

Cette incorporation d'un ou plusieurs éléments carburigènes a pour effet de forcer la précipitation de carbures spécifiques moins néfastes pour la résistance à la corrosion que les carbures de chrome.This incorporation of one or more carburigenic elements has the effect of forcing the precipitation of specific carbides less harmful to the corrosion resistance than chromium carbides.

Une deuxième variante de l'invention consiste à incorporer dans l'alliage, à la fois d'une part au moins un tel métal d'apport, et d'autre part du manganèse et de l'azote, pour ajuster les propriétés mécaniques de l'alliage. De préférence, dans cette deuxième variante, la composition en masse selon la revendication 1devient :

  • total de, d'une part le ou les métaux d'apport du premier ensemble ou de son sous-ensemble des PGM, et d'autre part le manganèse et l'azote : valeur mini 30%, valeur maxi 40 %
  • chrome : valeur mini 16%, valeur maxi 20 %
  • molybdène : valeur mini 0%, valeur maxi 2 %
  • cuivre : valeur mini 0%, valeur maxi 2 %
  • or : valeur mini 0%, valeur maxi 2 %
  • silicium : valeur mini 0%, valeur maxi 1 %
  • carbone : valeur mini 0%, valeur maxi 0,03 %
  • fer : le complément à 100 %.
A second variant of the invention consists in incorporating into the alloy, at the same time on the one hand at least one such filler metal, and on the other hand manganese and nitrogen, to adjust the mechanical properties of the alloy. Preferably, in this second variant, the mass composition according to claim 1follow:
  • total of, on the one hand, the filler metal (s) of the first set or its subset of GMPs, and on the other hand manganese and nitrogen: minimum value 30%, maximum value 40%
  • chrome: minimum value 16%, maximum value 20%
  • molybdenum: minimum value 0%, maximum value 2%
  • copper: minimum value 0%, maximum value 2%
  • gold: minimum value 0%, maximum value 2%
  • silicon: minimum value 0%, maximum value 1%
  • carbon: minimum value 0%, maximum value 0.03%
  • iron: the 100% supplement.

L'invention concerne encore un composant d'horlogerie ou de joaillerie réalisé en un tel alliage.The invention also relates to a watch or jewelery component made of such an alloy.

Claims (5)

  1. Stainless steel alloy with a base formed of iron and chromium, characterized in that the alloy includes less than 0.5% by mass of nickel and is arranged in an austenitic face-centred cubic structure and consists, in values by mass, of:
    - chromium: minimum value 16%, maximum value 20%;
    - at least one additional metal, the value of the total of said at least one additional metal or said additional metals being comprised between: minimum value 30% and maximum value 40%, said at least one additional metal being selected from among a first group comprising copper, ruthenium, rhodium, palladium, rhenium, osmium, iridium, platinum and gold:
    - the copper value being comprised between: minimum value 0% and maximum value 2%;
    - the gold value being comprised between: minimum value 0% and maximum value 2%;
    - carbon: minimum value 0%, maximum value 0.03%;
    - molybdenum: minimum value 0%, maximum value 2%;
    - manganese: minimum value 0%, maximum value 2%;
    - silicon: minimum value 0%, maximum value 1 %;
    - nitrogen: minimum value 0%, maximum value 0.1%;
    - within the limit of 0.5% in mass of the total, at least one carburigen element taken from among a second group including tungsten, vanadium, niobium, zirconium and titanium, to replace an equivalent mass of iron in the alloy;
    - iron and inevitable impurities: the complement to 100%.
  2. Alloy according to claim 1, characterized in that at least one said additional metal is selected from among a sub-group, called the platinoid group, of said first group, said platinoid sub-group including ruthenium, rhodium, palladium, rhenium, osmium, iridium and platinum.
  3. Alloy according to claim 2, characterized in that said at least one additional metal is exclusively selected from among said platinoid sub-group.
  4. Alloy according to any of claims 1 to 3, characterized in that the alloy consists, in values by mass, of:
    - chromium: 18%;
    - palladium: 35%;
    - carbon: 0% to 0.03%;
    - iron and inevitable impurities: the complement to 100%.
  5. Timepiece or jewellery component including made of an alloy according to any of the preceding claims.
EP12191101.0A 2012-11-02 2012-11-02 Edelstahllegierung ohne Nickel Active EP2728028B1 (en)

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EP12191101.0A EP2728028B1 (en) 2012-11-02 2012-11-02 Edelstahllegierung ohne Nickel
US14/425,455 US20150225820A1 (en) 2012-11-02 2013-10-17 Nickel free stainless steel alloy
PCT/EP2013/071770 WO2014067795A1 (en) 2012-11-02 2013-10-17 Nickel-free stainless steel alloy
RU2015120760A RU2625363C2 (en) 2012-11-02 2013-10-17 Stainless steel free of nickel
EP13785379.2A EP2914759B1 (en) 2012-11-02 2013-10-17 Edelstahllegierung ohne nickel
JP2015533640A JP5976945B2 (en) 2012-11-02 2013-10-17 Nickel free stainless steel alloy
CN201380057112.4A CN104769145B (en) 2012-11-02 2013-10-17 Stainless steel alloy without nickel
TW102138458A TWI586816B (en) 2012-11-02 2013-10-24 Nickel free stainless steel alloy
HK15112788.4A HK1211992A1 (en) 2012-11-02 2015-12-29 Nickel-free stainless steel alloy

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WO2014067795A1 (en) 2014-05-08
CN104769145B (en) 2016-10-19
HK1211992A1 (en) 2016-06-03
JP5976945B2 (en) 2016-08-24
US20150225820A1 (en) 2015-08-13
TW201432064A (en) 2014-08-16
TWI586816B (en) 2017-06-11
EP2914759A1 (en) 2015-09-09
CN104769145A (en) 2015-07-08
JP2015535888A (en) 2015-12-17
EP2728028A1 (en) 2014-05-07
RU2015120760A (en) 2016-12-27
EP2914759B1 (en) 2016-10-05
RU2625363C2 (en) 2017-07-13

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