EP0629714A1 - Martensitic stainless steel with improved machinability - Google Patents

Martensitic stainless steel with improved machinability Download PDF

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Publication number
EP0629714A1
EP0629714A1 EP94401246A EP94401246A EP0629714A1 EP 0629714 A1 EP0629714 A1 EP 0629714A1 EP 94401246 A EP94401246 A EP 94401246A EP 94401246 A EP94401246 A EP 94401246A EP 0629714 A1 EP0629714 A1 EP 0629714A1
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steel
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martensitic
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EP0629714B1 (en
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Olivier Bletton
Jacques Bayol
Pascal Terrien
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Ugitech SA
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Ugine Savoie SA
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    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/60—Ferrous alloys, e.g. steel alloys containing lead, selenium, tellurium, or antimony, or more than 0.04% by weight of sulfur
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon

Definitions

  • the present invention relates to a martensitic type stainless steel with improved machinability.
  • stainless steels iron alloys containing at least 10.5% chromium.
  • Martensite steels generally include 12 to 18% chromium and carbon contents of up to approximately 1%.
  • Many alloying elements, such as Ni, Mo, Si, Ti, V, Nb ... allow a wide range of properties and lead to applications as varied as: mechanical engineering, tools, cutlery, hot oxides ...
  • the structure of the final product and its mechanical characteristics largely depend on the heat treatments.
  • the three common treatments are quenching, tempering, and softening annealing.
  • the purpose of hardening is to give the steel a martensitic structure and a very high hardness.
  • the tempering increases the ductility which is very low after quenching and the softening annealing makes it possible to obtain a metal which can undergo sophisticated processing operations, such as certain modes of machining or forming.
  • Martensitic stainless steels are difficult to machine. There are several reasons for this.
  • Tool wear therefore has different origins for martensitic steels (high hardness, high friction) than for austenitic steels (work hardening, poor thermal conductivity, poor chip fractionation).
  • selenium serves as a complement to the sulfur, it tends to globulate the sulphides and thereby improves the mechanical characteristics in the cross direction. In addition to the cost, this element is highly toxic.
  • tellurium also makes it possible to globulate the sulphides, and therefore tends to reduce the anisotropy of the steel, in particular the anisotropy of its mechanical properties. It also improves, in itself, the machinability but has the drawback of reducing the ability to be processed hot. For this reason, its use is limited.
  • FR-A-2 648 477 discloses a resulfurized austenitic steel with improved machinability containing in its weight composition a proportion of calcium and oxygen which improves the machinability.
  • austenitic stainless steels are difficult to machine, largely because of their low thermal conductivity, resulting in poor flow of the heat produced at the tip of a cutting tool and rapid deterioration. of the tool and their high hardenability locally inducing zones of high hardness.
  • austenitic steels do not require any significant heat treatment capable of modifying the physico-chemical state of the steel and of the inclusions.
  • Martensitic steels are hardenable and have the characteristics of being of high hardness. As a result, the problem of the difficulty of the machining is not entirely resolved.
  • the object of the invention is to reduce the difficulties encountered in the machining of martensitic steels, while retaining their hot and cold deformability or forgeability properties, their mechanical characteristics and their particularities in heat treatments.
  • Martensitic steels have completely different compositions and above all a structure, compared to steels, for example austenitic.
  • the behavior of martensitic steels during machining is linked to specific problems.
  • a change in the composition of martensitic steels does not surely make it possible to preserve their properties or even more to improve them.
  • Martensitic steels are hardenable and have the characteristics of being of high hardness.
  • These steels are metallurgically very different from austenitic steels. On the one hand, they can be quenched and the crystalline structure obtained when cold on these steels is not comparable to the austenitic structure.
  • Tempering rapid cooling from a high temperature below a temperature at the start of martensitic transformation which depends on the composition of the steel
  • income maintenance at an intermediate temperature depending on the steel
  • martensitic steels undergo softening treatments. The latter is used when the metal has to undergo sophisticated processing operations, such as certain machining or forming modes.
  • the metal structure is no longer a martensitic structure, but a ferritic structure with chromium carbides at the grain boundaries.
  • martensitic steels are very different from that of austenitic steels, which is partly explained by the need to have the martensitic transformation start temperature Ms high enough. They contain little nickel (minus 6%), low chromium contents for stainless steels (11 to 19% chromium).
  • the chosen oxides that is to say lime silicoaluminates of the anorthide and / or pseudowollastonite and / orabilityite type represented on the diagram ternary of FIG. 1, retain the main properties of martensitic steel after the heat treatments that said steel undergoes, without degradation of the mechanical properties and by significantly improving the machinability properties,
  • the gain in machinability is in no case made at the expense of characteristics such as forgeability or hot or cold deformability.
  • the introduction of the malleable oxides is done without taking into account the level of carbon added with nitrogen, the reduction of which, as it is proven, tends to reduce the mechanical characteristics.
  • the invention also relates to a martensitic steel in which it has been added, in its composition by weight from 2 to 6% of nickel and from 1 to 5% of copper or even less than 3% of molybdenum.
  • Nickel is necessary in steels containing more than 16% chromium to obtain, after quenching, a martensitic structure.
  • nickel in addition to its role previously mentioned (reduction in the quantity of delta ferrite), will form with copper the "NI3Cu” phase which will harden the metal. Curing is not obtained here only by carbon, which, moreover, is relatively low.
  • Copper allows in combination with metal to obtain a structural hardening and therefore to increase the mechanical characteristics.
  • Molybdenum improves resistance to corrosion and has a beneficial effect on hardness after tempering and it also improves resilience.
  • steel A contains, on a residual basis, less than 0.5% of nickel and less than 0.2% of copper.
  • This steel was compared to two reference steels, the compositions of which are as follows: VS Yes Mn Or Ref. 1 0.184 0.359 0.530 0.180 Ref. 2 0.194 0.364 0.731 0.313 Cr Mo Cu S P NOT 12.63 0.135 0.084 0.022 0.018 0.056 12.77 0.093 0.088 0.002 0.017 0.049
  • the turning is carried out with solid carbide inserts, test designated by Vb 30 / 0.3, which consists in determining the speed for which the wear in clearance is 0.3mm after 30mn of machining and also, with inserts in coated carbide, test designated by Vb 15 / 0.15 which consists in determining the speed at which the wear in clearance is 0.15 mm after 15 minutes of machining.
  • a martensitic steel according to the invention and the only weight composition of which is as follows: VS Yes Mn Cr Mo STEEL B 0.196 0.444 0.555 12.10 0.073 9 P NOT It O Ca / O SteelB 0.0263 0.019 0.053 41.10 ⁇ 4 99.10 ⁇ 4 0.41
  • steel B contains, on a residual basis, less than 0.5% of nickel and less than 0.2% of copper.
  • This steel was compared to a standard reference steel which does not contain malleable oxides in its composition and whose composition is as follows: VS Yes Mn Or Cr Mo REF 3 0.214 0.344 0.564 0.354 12.32 0.097 Cu S P NOT It O Ca / O REF 3 0.106 0.261 0.017 0.054 45.10 ⁇ 4
  • Table 3 below presents characteristic values of the machining tests and shows that the steels treated according to the invention give a machinability gain of 25 to 30%.
  • METALLURGICAL CONDITION TREATY SOFTENED test Vb 30 / 0.3 (m / min) Vb 15 / 0.15 (m / min) Vb 30 / 0.3 (m / min) Vb 15 / 0.15 (m / min) Steel ref 1 195 250 - - Steel ref 2 150 205 - - Steel ref 3 230 250 200 220 Steel A 250 - - - Steel B 250 290 - - TABLE 3
  • These reference steels contain copper and nickel in their composition and are among the grades with structural hardening.
  • the steel D according to the invention was treated by machining in the quenched state. This means that it has been quenched at 1050 ° C in oil. It appeared, as shown on the curves of FIG. 2, that the presence of malleable oxides did indeed increase the machinability which is observed on the curves by the reduction in the wear of the tools. This wear actually goes from 0.15 mm after 15 minutes of machining at a speed of 190 m / min, an advance of 0.15 mm / revolution, a depth of cut of 1.5 mm for steel reference 4 , at a wear of 0.125 mm for steel D.
  • Steel D according to the invention made it possible to obtain in the softened state a cutting speed of 240 m / min while reference steel 5 allowed a cutting speed of 210 m / min.
  • the gain recorded is 20%.
  • martensitic steels containing in their composition malleable oxides have improved machinability, the oxides not deteriorating the other characteristics of said steels.

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Abstract

Martensitic stainless steel with improved machinability, characterised in that its composition by weight is the following: - carbon lower than 1.2 % - silicon lower than or equal to 2 % - manganese lower than or equal to 2 % - chromium: 10.5 < Cr < 19 % - sulphur lower than or equal to 0.55 % - calcium higher than 32 x 10<-4> % - oxygen higher than 70 x 10<-4> %, - the ratio of the calcium and oxygen contents Ca/O being 0.2 < Ca/O < 0.6, the said steel being subjected to at least one quenching heat treatment in order to give it a martensitic structure.

Description

La présente invention concerne un acier inoxydable du type martensitique à usinabilité améliorée.The present invention relates to a martensitic type stainless steel with improved machinability.

On désigne par aciers inoxydables les alliages de fer contenant au moins 10,5% de chrome.By stainless steels is meant iron alloys containing at least 10.5% chromium.

D'autres éléments entrent dans la composition de l'acier afin de modifier la structure et les propriétés de l'alliage. Les quatre principales structures sont:

  • les aciers martensitiques,
  • les aciers ferritiques,
  • les aciers austénitiques,
  • les aciers austéno-ferritiques.
Other elements enter into the composition of the steel in order to modify the structure and the properties of the alloy. The main four are:
  • martensitic steels,
  • ferritic steels,
  • austenitic steels,
  • austenitic-ferritic steels.

Les aciers martensites comprennent en général 12 à 18% de chrome et des teneurs en carbone pouvant aller jusqu'à 1% environ. De nombreux éléments d'alliage, tels Ni,Mo, Si, Ti, V, Nb... permettent un large éventail de propriétés et conduisent à des applications aussi variées que : construction mécanique, outillage, coutellerie, oxydes à chaud...Martensite steels generally include 12 to 18% chromium and carbon contents of up to approximately 1%. Many alloying elements, such as Ni, Mo, Si, Ti, V, Nb ... allow a wide range of properties and lead to applications as varied as: mechanical engineering, tools, cutlery, hot oxides ...

Leur originalité est d'allier à une bonne résistance à la corrosion due essentiellement au chrome, des caractéristiques mécaniques élevées qui s'expliquent par la structure martensitique.Their originality is to combine good resistance to corrosion mainly due to chromium, high mechanical characteristics which are explained by the martensitic structure.

Il existe une vaste étendue d'aciers inoxydables martensitiques, aux compositions et propriétés d'emploi très variées. Parmi les nuances les plus courantes, on peut citer :

  • les nuances au chrome-carbone sans nickel. Les caractéristiques recherchées sont la dureté, la résistance à la corrosion, la polissabilité.
  • les nuances à 16% de chrome plus nickel. La présence de chrome leur confère une bonne résistance à la corrosion, le nickel (2 à 4%) permet d'obtenir une structure martensitique après trempe.
  • les nuances à durcissement structural. Elles ont une excellente résistance à la corrosion avec de hautes caractéristiques mécaniques.
  • les 12% de chrome améliorées (addition d'éléments comme le vanadium, le molybdène, le tungstène, le silicium, le niobium, le titane...). Le but est d'optimiser une ou plusieurs propriétés d'emploi du matériau, comme résistance à chaud, le fluage, le résilience, la résistance à la corrosion...
There is a wide range of martensitic stainless steels, with very varied compositions and properties of use. Among the most common nuances, we can cite:
  • nickel-free chrome-carbon grades. The characteristics sought are hardness, corrosion resistance, polishability.
  • shades with 16% chromium plus nickel. The presence of chromium gives them good resistance to corrosion, nickel (2 to 4%) makes it possible to obtain a martensitic structure after quenching.
  • structural hardening grades. They have excellent resistance to corrosion with high mechanical characteristics.
  • 12% improved chromium (addition of elements such as vanadium, molybdenum, tungsten, silicon, niobium, titanium ...). The aim is to optimize one or more properties of use of the material, such as hot resistance, creep, resilience, corrosion resistance ...

Pour toutes ces nuances, la structure du produit final et ses caractéristiques mécaniques dépendent largement des traitements thermiques. Les trois traitements courants sont la trempe, le revenu et le recuit d'adoucissement.For all these nuances, the structure of the final product and its mechanical characteristics largely depend on the heat treatments. The three common treatments are quenching, tempering, and softening annealing.

La trempe a pour but de donner à l'acier une structure martensitique et une dureté très élevée.The purpose of hardening is to give the steel a martensitic structure and a very high hardness.

Le revenu permet d'augmenter la ductilité qui est très faible après la trempe et le recuit d'adoucissement permet d'obtenir un métal pouvant subir des opérations de mise en oeuvre sophistiquées, telles que certains modes d'usinage ou de formage.The tempering increases the ductility which is very low after quenching and the softening annealing makes it possible to obtain a metal which can undergo sophisticated processing operations, such as certain modes of machining or forming.

Tous les traitements sont définis en fonction de la composition de la nuance (ajustement de la température de revenu, de sa durée, du type de refroidissement...).All the treatments are defined according to the composition of the shade (adjustment of the tempering temperature, its duration, the type of cooling, etc.).

Les aciers inoxydables martensitiques sont difficiles à usiner. Plusieurs raisons expliquent cet état de fait.Martensitic stainless steels are difficult to machine. There are several reasons for this.

En effet, leur grande dureté provoque une fatigue mécanique des outils qui subissent des efforts de coupe très importants et peuvent voir leur limite de rupture dépassée.Indeed, their great hardness causes mechanical fatigue of the tools which undergo very significant cutting forces and can see their breaking limit exceeded.

Par ailleurs, les forces de frottements élevées, ajoutées à une conductivité thermique médiocre vont induire des températures élevées à l'interface outil/matière, d'où une fatigue thermique et une dégradation par diffusion.Furthermore, the high friction forces, added to a poor thermal conductivity, will induce high temperatures at the interface. tool / material, resulting in thermal fatigue and degradation by diffusion.

D'autre part, les domaines de fractionnement des copeaux sont bien souvent réduits.On the other hand, the areas of fractionation of the chips are very often reduced.

Enfin, la présence d'oxydes durs tels que l'alumine ou la chromite est un facteur aggravant l'usure des outils de coupe.Finally, the presence of hard oxides such as alumina or chromite is an aggravating factor for the wear of cutting tools.

Les usures des outils ont donc des origines différentes pour les aciers martensitiques (dureté élevée, frottements importants) que pour les aciers austénitiques (écrouissabilité, mauvaise conductivité thermique mauvais fractionnement des copeaux).Tool wear therefore has different origins for martensitic steels (high hardness, high friction) than for austenitic steels (work hardening, poor thermal conductivity, poor chip fractionation).

De nombreuses voies sont utilisées pour améliorer l'usinabilité, mais toutes ont des inconvénients.Many routes are used to improve machinability, but all have drawbacks.

L'addition du soufre, qui va former avec le manganèse des sulfures, parfois substitués au chrome, détériore la résistance à la corrosion, la déformabilité à chaud et à froid, la soudabilité, ainsi que les caractéristiques mécaniques en sens travers.The addition of sulfur, which will form with manganese sulfides, sometimes substituted for chromium, deteriorates corrosion resistance, hot and cold deformability, weldability, as well as the mechanical characteristics in the cross direction.

L'addition de sélénium sert de complément au soufre, il tend à globuliser les sulfures et améliore de ce fait les caractéristiques mécaniques en sens travers. En plus du coût, cet élément est hautement toxique.The addition of selenium serves as a complement to the sulfur, it tends to globulate the sulphides and thereby improves the mechanical characteristics in the cross direction. In addition to the cost, this element is highly toxic.

L'addition de tellure permet, elle aussi, de globuliser les sulfures, et tend donc à diminuer l'anisotropie de l'acier en particulier l'anisotropie de ses propriétés mécaniques. Il améliore également, en soi, l'usinabilité mais a l'inconvénient de réduire l'aptitude à la transformation à chaud. Pour cette raison, son emploi est limité.The addition of tellurium also makes it possible to globulate the sulphides, and therefore tends to reduce the anisotropy of the steel, in particular the anisotropy of its mechanical properties. It also improves, in itself, the machinability but has the drawback of reducing the ability to be processed hot. For this reason, its use is limited.

L'addition de plomb qui est insoluble dans l'acier apparait sous forme de nodules sphériques, mais cet élément à l'inconvénient d'être toxique et de dégrader la forgeabilité.The addition of lead which is insoluble in steel appears in the form of spherical nodules, but this element has the disadvantage of being toxic and of degrading forgeability.

On connaît par le FR-A-2 648 477, un acier austénitique résulfuré à usinabilité améliorée contenant dans sa composition pondérale une proportion de calcium et d'oxygène qui améliore l'usinabilité.FR-A-2 648 477 discloses a resulfurized austenitic steel with improved machinability containing in its weight composition a proportion of calcium and oxygen which improves the machinability.

Or, il est bien connu que les aciers inoxydables austénitiques sont difficiles à usiner, en grande partie à cause de leur faible conductibilité thermique, d'où un mauvais écoulement de la chaleur produite à la pointe d'un outil de coupe et une détérioration rapide de l'outil et de leur forte écrouissabilité induisant localement des zones de dureté élevée.However, it is well known that austenitic stainless steels are difficult to machine, largely because of their low thermal conductivity, resulting in poor flow of the heat produced at the tip of a cutting tool and rapid deterioration. of the tool and their high hardenability locally inducing zones of high hardness.

Pendant l'usinage de l'acier, du fait des températures de coupe élevées, ces inclusions jouent un rôle lubrifiant à l'interface-acier à usiner-outil de coupe, conduisant ainsi à une usure réduite des outils de coupe et à un meilleur aspect de surface des pièces usinées.During the machining of steel, due to the high cutting temperatures, these inclusions play a lubricating role at the interface-steel to be machined-cutting tool, thus leading to reduced wear of the cutting tools and to better surface appearance of the machined parts.

De plus, dans le domaine de l'usinage, les aciers austénitiques ne nécessitent pas de traitement thermique important susceptible de modifier l'état physico-chimique de l'acier et des inclusions.In addition, in the field of machining, austenitic steels do not require any significant heat treatment capable of modifying the physico-chemical state of the steel and of the inclusions.

Les aciers martensitiques sont eux trempables et ont pour caractéristiques d'être de haute dureté. De ce fait, le problème de la difficulté de l'usinage n'est pas résolu entièrement.Martensitic steels are hardenable and have the characteristics of being of high hardness. As a result, the problem of the difficulty of the machining is not entirely resolved.

L'invention a pour but de réduire les difficultés rencontrées dans l'usinage des aciers martensitiques, tout en conservant leurs propriétés de déformabilité ou forgeabilité à chaud et à froid, leurs caractéristiques mécaniques et leurs particularités aux traitements thermiques.The object of the invention is to reduce the difficulties encountered in the machining of martensitic steels, while retaining their hot and cold deformability or forgeability properties, their mechanical characteristics and their particularities in heat treatments.

L'invention a pour objet un acier martensitique à haute usinabilité, qui se caractérise par la composition pondérale suivante :

  • carbone inférieur à 1,2%
  • silicium inférieur ou égal à 2%
  • manganèse inférieur ou égal à 2%
  • chrome : 10,5<Cr<19%
  • soufre inférieur ou égal à 0,55%
  • calcium supérieur à 32.10⁻⁴%
  • oxygène supérieur à 70.10⁻⁴%
  • le rapport de la teneur en calcium et en oxygène Ca/O étant 0,2<Ca/O<0,6, ledit acier étant soumis à au moins un traitement thermique de trempe pour lui conférer une structure martensitique.
The subject of the invention is a martensitic steel with high machinability, which is characterized by the following weight composition:
  • carbon less than 1.2%
  • silicon less than or equal to 2%
  • manganese less than or equal to 2%
  • chromium: 10.5 <Cr <19%
  • sulfur less than or equal to 0.55%
  • calcium greater than 32.10⁻⁴%
  • oxygen greater than 70.10⁻⁴%
  • the ratio of the calcium and oxygen content Ca / O being 0.2 <Ca / O <0.6, said steel being subjected to at least one quenching heat treatment to give it a martensitic structure.

Selon d'autres caractéristiques de l'invention :

  • l'acier comprend du soufre dans une proportion inférieure ou égale à 0,035%,
  • l'acier comprend du soufre dans une proportion 0,15%<S<0,45%, ledit acier étant resulfuré,
  • l'acier comprend, en outre, du nickel dans une proportion inférieure ou égale à 6%,
  • l'acier comprend, en outre, du molybdène dans une proportion inférieure ou égale à 3%,
  • l'acier comprend, en outre, dans sa composition pondérale des éléments choisis parmi le tungstène, le cobalt, le niobium, le titane, le tantale, le zirconium, le vanadium, le molybdène dans les proportions pondérales suivantes :
    • tungstène inférieur ou égal à 4%
    • cobalt inférieur ou égal à 4,5%
    • niobium inférieur ou égal à 1%
    • titane inférieur ou égal à 1%
    • tantale inférieur ou égal à 1%
    • zirconium inférieur ou égal à 1%
    • vanadium inférieur ou égal à 1%
    • molybdène inférieur ou égale à 3%,
  • l'acier comprend du nickel dans une proportion 2%<Ni<6% et du cuivre dans une proportion de 1%<Cu<5%
  • l'acier contient des inclusions de silicoaluminate de chaux du type anorthide et/ou pseudo-wollastonite et/ou géhlénite.
According to other characteristics of the invention:
  • the steel comprises sulfur in a proportion less than or equal to 0.035%,
  • the steel comprises sulfur in a proportion 0.15% <S <0.45%, said steel being resulfurized,
  • the steel also comprises nickel in a proportion less than or equal to 6%,
  • the steel also comprises molybdenum in a proportion less than or equal to 3%,
  • the steel furthermore comprises, in its weight composition, elements chosen from tungsten, cobalt, niobium, titanium, tantalum, zirconium, vanadium, molybdenum in the following weight proportions:
    • tungsten less than or equal to 4%
    • cobalt less than or equal to 4.5%
    • niobium less than or equal to 1%
    • titanium less than or equal to 1%
    • tantalum less than or equal to 1%
    • zirconium less than or equal to 1%
    • vanadium less than or equal to 1%
    • molybdenum less than or equal to 3%,
  • the steel includes nickel in a proportion 2% <Ni <6% and copper in a proportion of 1% <Cu <5%
  • the steel contains inclusions of lime silicoaluminate of the anorthide and / or pseudo-wollastonite and / or gehenite type.

Les essais décrits ci-dessous et les figures annexées feront mieux comprendre l'invention.

  • la figure 1 représente sur diagramme ternaire SiO₂ - CaO - Al₂O₃ donnant les compositions des oxydes introduit dans l'acier selon l'invention,
  • la figure 2 montre des courbes représentant l'évolution de l'usure d'un outil pour différents exemples donnés.
The tests described below and the appended figures will make the invention better understood.
  • FIG. 1 represents on a ternary diagram SiO₂ - CaO - Al₂O₃ giving the compositions of the oxides introduced into the steel according to the invention,
  • FIG. 2 shows curves representing the evolution of the wear of a tool for various examples given.

Les aciers martensitiques ont des compositions et surtout une structure totalement différentes, par rapport aux aciers, par exemple austénitiques. Les comportements des aciers martensitiques lors de l'usinage sont liés à des problèmes spécifiques.Martensitic steels have completely different compositions and above all a structure, compared to steels, for example austenitic. The behavior of martensitic steels during machining is linked to specific problems.

Une modification de la composition des aciers martensitiques ne permet pas de façon sûre de conserver leurs propriétés ou plus encore de les améliorer.A change in the composition of martensitic steels does not surely make it possible to preserve their properties or even more to improve them.

Les aciers martensitiques sont trempables et ont pour caractéristiques d'être de haute dureté.Martensitic steels are hardenable and have the characteristics of being of high hardness.

Ces aciers sont métallurgiquement très différents des aciers austénitiques. D'une part, ils peuvent subir la trempe et la structure cristalline obtenue à froid sur ces aciers n'est pas comparable à la structure austénitique.These steels are metallurgically very different from austenitic steels. On the one hand, they can be quenched and the crystalline structure obtained when cold on these steels is not comparable to the austenitic structure.

D'autre part, l'élaboration des aciers martensitiques diffère en de nombreux points de celle des aciers austénitiques.On the other hand, the development of martensitic steels differs in many points from that of austenitic steels.

En particulier, les traitements thermiques sont nombreux sur les premiers et confèrent au métal ses caractéristiques d'emploi. La trempe (refroidissement rapide depuis une haute température en dessous d'une température Ms de début de transformation martensitique qui dépend de la composition de l'acier) permet d'obtenir, à partir d'une structure austénitique à chaud, une structure martensitique. Elle est généralement suivie d'un revenu (maintien à une température intermédiaire dépendant de l'acier) qui permet d'augmenter la ductilité qui est très faible après trempe.In particular, there are many heat treatments on the former and give the metal its characteristics of use. Tempering (rapid cooling from a high temperature below a temperature at the start of martensitic transformation which depends on the composition of the steel) makes it possible to obtain, from a hot austenitic structure, a martensitic structure. It is generally followed an income (maintenance at an intermediate temperature depending on the steel) which makes it possible to increase the ductility which is very low after quenching.

Certaines nuances d'aciers martensitiques subissent des traitements d'adoucissement. Ce dernier est utilisé lorsque le métal doit subir des opérations de mise en oeuvre sophistiquées, telles que certains modes d'usinage ou de formage. La structure du métal n'est alors plus une structure martensitique, mais une structure ferritique avec des carbures de chrome au niveau des joints de grains.Certain grades of martensitic steels undergo softening treatments. The latter is used when the metal has to undergo sophisticated processing operations, such as certain machining or forming modes. The metal structure is no longer a martensitic structure, but a ferritic structure with chromium carbides at the grain boundaries.

Cependant, il retrouve sa structure martensitique et ses caractéristiques mécaniques après des traitements thermiques appropriés.However, it regains its martensitic structure and its mechanical characteristics after appropriate heat treatments.

Enfin, la composition chimique des aciers martensitiques est très différente de celle des aciers austénitiques ce qui s'explique d'ailleurs en partie par la nécessité d'avoir la température de début de transformation martensitique Ms suffisamment haute. Ils ne contiennent que peu de nickel (moins 6%), des teneurs en chrome basses pour des aciers inoxydables (de 11 à 19% de chrome).Finally, the chemical composition of martensitic steels is very different from that of austenitic steels, which is partly explained by the need to have the martensitic transformation start temperature Ms high enough. They contain little nickel (minus 6%), low chromium contents for stainless steels (11 to 19% chromium).

Selon l'invention, l'acier martensitique se caractérise par sa composition pondérale suivante :

  • carbone inférieur à 1,2%
  • silicium inférieur ou égal à 2%
  • manganèse inférieur ou égal à 2%
  • chrome : 10,5<Cr<19%
  • soufre inférieur ou égal à 0,4%
  • calcium supérieur à 32.10⁻⁴%
  • oxygène supérieur à 70.10⁻⁴%,

   le rapport de la teneur en calcium et en oxygène Ca/O étant 0,2<Ca/O<0,6,ledit acier étant soumis à au moins une trempe pour lui conférer une structure martensitique.According to the invention, martensitic steel is characterized by its following weight composition:
  • carbon less than 1.2%
  • silicon less than or equal to 2%
  • manganese less than or equal to 2%
  • chromium: 10.5 <Cr <19%
  • sulfur less than or equal to 0.4%
  • calcium greater than 32.10⁻⁴%
  • oxygen higher than 70.10⁻⁴%,

the ratio of the calcium and oxygen content Ca / O being 0.2 <Ca / O <0.6, said steel being subjected to at least one quenching to give it a martensitic structure.

D'une façon inattendue, en introduisant des oxydes malléables dans une composition martensitique, il s'est avéré que les oxydes choisis, c'est à dire des silicoaluminates de chaux du type anorthide et/ou pseudowollastonite et/ou géhlénite representés sur le diagramme ternaire de la figure 1, conservent les propriétés principales à l'acier martensitique après les traitements thermiques que ledit acier subit, sans dégradation des propriétés mécaniques et en améliorant de façon notable les propriétés d'usinabilité,Unexpectedly, by introducing malleable oxides into a martensitic composition, it turned out that the chosen oxides, that is to say lime silicoaluminates of the anorthide and / or pseudowollastonite and / or gehenite type represented on the diagram ternary of FIG. 1, retain the main properties of martensitic steel after the heat treatments that said steel undergoes, without degradation of the mechanical properties and by significantly improving the machinability properties,

Or, les inclusions d'oxydes malléables n'ont une action favorable pour l'usinabilité uniquement parce que la matrice s'y prête.However, the inclusions of malleable oxides have a favorable action for machinability only because the matrix lends itself to it.

La Demanderesse a été surprise de constater que dans une matrice de structure aussi différente que la structure des aciers martensitiques, ces oxydes ont aussi un effet bénéfique sur l'usinabilité.The Applicant was surprised to find that in a matrix with a structure as different as the structure of martensitic steels, these oxides also have a beneficial effect on the machinability.

De plus, il n'était pas évident que, du fait des différences d'élaboration, la Demanderesse arrive à obtenir le même type d'inclusions dans l'acier.In addition, it was not obvious that, due to the differences in preparation, the Applicant managed to obtain the same type of inclusions in the steel.

La Demanderesse a en particulier eu la surprise de constater que les traitements thermiques ne changaient rien à la nature des inclusions.The Applicant was in particular surprised to find that the heat treatments did not change the nature of the inclusions.

Il ne se produit pas, ou du moins pas de manière significative de modification de la composition analytique des inclusions, entre autre par diffusion à l'état solide et cela au cours des traitements thermiques que subissent les aciers martensitiques.There is no, or at least no significant change in the analytical composition of the inclusions, inter alia by diffusion in the solid state, and this during the heat treatments undergone by martensitic steels.

Les problèmes de l'usinage des aciers martensitiques sont en outre très différents des problèmes posés par les aciers austénitiques.The problems of machining martensitic steels are also very different from the problems posed by austenitic steels.

Contrairement à ces derniers, ils ne sont pas écrouissables et leur conductivité thermique n'est pas aussi mauvaise.Unlike these, they are not hardenable and their thermal conductivity is not as bad.

Par contre, le principal problème des aciers martensitiques pour l'usinage est la dureté.On the other hand, the main problem of steels Martensitics for machining is hardness.

Rien ne permettait de penser que des inclusions identiques puissent avoir un effet bénéfique alors que les problèmes d'usinage avaient des causes si différentes.There was nothing to suggest that identical inclusions could have a beneficial effect when the machining problems had such different causes.

Il s'est avéré que lors de l'usinage des aciers martensitiques, les oxydes malléables, aux températures d'usinage de ces aciers, sont suffisamment chauffés pour former un film lubrifiant en permanence régénéré par les inclusions d'oxydes présents dans le métal. Ce film lubrifiant permet de diminuer les frottements de la matière sur l'outil. Ainsi, l'effet de la charge importante due à la grande dureté du matériau se trouve réduit.It has been found that during the machining of martensitic steels, the malleable oxides, at the machining temperatures of these steels, are sufficiently heated to form a lubricating film permanently regenerated by the oxide inclusions present in the metal. This lubricating film makes it possible to reduce the friction of the material on the tool. Thus, the effect of the high load due to the high hardness of the material is reduced.

Deux familles d'aciers martensitiques ont été testés, l'une comprenant dans sa composition pondérale du soufre dans une proportion comprise entre 0,15 et 0,45%, l'autre comprenant dans sa composition pondérale du soufre dans une proportion inférieure à 0,035%.Two families of martensitic steels were tested, one comprising in its weight composition of sulfur in a proportion of between 0.15 and 0.45%, the other comprising in its weight composition of sulfur in a proportion of less than 0.035 %.

Il a été remarqué, que la présence des oxydes malléables dans l'acier ne modifie pas la résistance à la corrosion, soit par piqûre, soit caverneuse, aussi bien pour la composition à bas soufre que dans la composition resulfurée.It has been observed that the presence of malleable oxides in the steel does not modify the resistance to corrosion, either by pitting or cavity, both for the low sulfur composition and in the resulfurized composition.

D'une manière générale, le gain apporté en usinabilité n'est fait, en aucun cas, au détriment de caractéristiques telles que la forgeabilité ou la déformabilité à chaud ou à froid.In general, the gain in machinability is in no case made at the expense of characteristics such as forgeability or hot or cold deformability.

Il a été également remarqué, que les oxydes introduits gardent leurs propriétés quelque soit le traitement thermique effectué.It has also been noted that the introduced oxides retain their properties whatever the heat treatment carried out.

Selon l'invention, l'introduction des oxydes malléables se fait sans tenir compte du taux de carbone additionné d'azote dont la diminution, tend comme il est prouvé, à diminuer les caractéristiques mécaniques.According to the invention, the introduction of the malleable oxides is done without taking into account the level of carbon added with nitrogen, the reduction of which, as it is proven, tends to reduce the mechanical characteristics.

L'invention concerne également un acier martensitique dans lequel il a été ajouté, dans sa composition pondérale de 2 à 6% de nickel et de 1 à 5% de cuivre ou encore moins de 3% de molybdène.The invention also relates to a martensitic steel in which it has been added, in its composition by weight from 2 to 6% of nickel and from 1 to 5% of copper or even less than 3% of molybdenum.

Le nickel est nécessaire dans des aciers contenant plus de 16% de chrome pour obtenir, après la trempe, une structure martensitique.Nickel is necessary in steels containing more than 16% chromium to obtain, after quenching, a martensitic structure.

Dans la nuance dites à durcissement structural, le nickel, outre son rôle précédemment évoqué (diminution de la quantité de ferrite delta), va former avec le cuivre la phase "NI₃Cu" qui va durcir le métal. Le durcissement n'est pas ici obtenu seulement par le carbone, qui du reste est relativement bas.In the grade known as structural hardening, nickel, in addition to its role previously mentioned (reduction in the quantity of delta ferrite), will form with copper the "NI₃Cu" phase which will harden the metal. Curing is not obtained here only by carbon, which, moreover, is relatively low.

Le cuivre permet en combinaison avec le métal d'obtenir un durcissement structural et donc d'augmenter les caractéristiques mécaniques.Copper allows in combination with metal to obtain a structural hardening and therefore to increase the mechanical characteristics.

Le molybdène améliore la résistance à la corrosion et a un effet bénéfique sur la dureté après un revenu et il améliore également la résilience.Molybdenum improves resistance to corrosion and has a beneficial effect on hardness after tempering and it also improves resilience.

L'acier martensitique selon l'invention peut contenir également des éléments stabilisant choisis parmi le tungstène, le cobalt, le niobium, le titane, le tantale, le zirconium dans les proportions pondérales suivantes :

  • tungstène inférieur ou égal à 4%
  • cobalt inférieur ou égal à 4,5%
  • niobium inférieur ou égal à 1%
  • titane inférieur ou égal à 1%
  • tantale inférieur ou égal à 1%
  • zirconium inférieur ou égal à 1%.
The martensitic steel according to the invention may also contain stabilizing elements chosen from tungsten, cobalt, niobium, titanium, tantalum, zirconium in the following weight proportions:
  • tungsten less than or equal to 4%
  • cobalt less than or equal to 4.5%
  • niobium less than or equal to 1%
  • titanium less than or equal to 1%
  • tantalum less than or equal to 1%
  • zirconium less than or equal to 1%.

Dans un exemple d'application un acier martensitique A selon l'invention dont la composition est la suivante :

Figure imgb0001
Figure imgb0002
dans laquelle il est introduit :
   Ca = 30.10⁻⁴%
   O = 129.10⁻⁴ %
   le rapport de la teneur en calcium et un oxygène Ca/O étant égal à 0,22.In an example of application, a martensitic steel A according to the invention, the composition of which is as follows:
Figure imgb0001
Figure imgb0002
in which it is introduced:
Ca = 30.10⁻⁴%
O = 129.10⁻⁴%
the ratio of calcium content and Ca / O oxygen being 0.22.

Dans cet exemple, l'acier A contient, à titre résiduel, moins de 0,5% de nickel et moins de 0,2% de cuivre.In this example, steel A contains, on a residual basis, less than 0.5% of nickel and less than 0.2% of copper.

Cet acier a été comparé à deux aciers de référence dont les compositions sont les suivantes : C Si Mn Ni Ref. 1 0,184 0,359 0,530 0,180 Ref. 2 0,194 0,364 0,731 0,313 Cr Mo Cu S P N 12,63 0,135 0,084 0,022 0,018 0,056 12,77 0,093 0,088 0,002 0,017 0,049 This steel was compared to two reference steels, the compositions of which are as follows: VS Yes Mn Or Ref. 1 0.184 0.359 0.530 0.180 Ref. 2 0.194 0.364 0.731 0.313 Cr Mo Cu S P NOT 12.63 0.135 0.084 0.022 0.018 0.056 12.77 0.093 0.088 0.002 0.017 0.049

Les trois aciers ont subit des tests d'usinabilité de tournage.All three steels have undergone turning machinability tests.

Le tournage est effectué avec des plaquettes en carbure massif, test désigné par Vb 30/0,3, qui consiste à déterminer la vitesse pour laquelle l'usure en dépouille est de 0,3mm après 30mn d'usinage et également, avec des plaquettes en carbure revêtu, test désigné par Vb 15/0,15 qui consiste à déterminer la vitesse pour laquelle l'usure en dépouille est de 0,15 mm après 15mn d'usinage.The turning is carried out with solid carbide inserts, test designated by Vb 30 / 0.3, which consists in determining the speed for which the wear in clearance is 0.3mm after 30mn of machining and also, with inserts in coated carbide, test designated by Vb 15 / 0.15 which consists in determining the speed at which the wear in clearance is 0.15 mm after 15 minutes of machining.

On constate sur le tableau 1 ci-dessous que les propriétés mécaniques ne sont nullement altérées par l'introduction d'inclusions d'oxydes malléables pour deux traitements thermiques d'adoucissement, c'est à dire comportant une trempe à l'huile à 950°C, un maintien pendant quatre heures à 820°C, un refroidissement lent jusqu'à 650°C, puis un refroidissement à l'air et "traité" c'est à dire ayant subit une trempe à 950°C, un revenu à 640°C et un refroidissement à l'air. NUANCE TRAITEMENT THERMIQUE Rm MPa INV A ADOUCI 535 REF 2 ADOUCI 544 REF 1 ADOUCI 544 INV A TRAITE 858 REF 2 TRAITE 967 REF 1 TRAITE 899 Rp0,2 MPa A% Z% DURETE HRB/HRC 282 29 82 296 29,2 64,1 82,3 HRB 280 28,6 60,6 80,6 HRB 737 14 51 837 12 52,6 29,1 HRC 754 15,5 55,8 27,3 HRC TABLEAU 1 It can be seen in table 1 below that the mechanical properties are in no way altered by the introduction of inclusions of malleable oxides for two thermal softening treatments, that is to say comprising oil quenching at 950 ° C, holding for four hours at 820 ° C, slow cooling down to 650 ° C, then air cooling and "treated" ie having undergone quenching at 950 ° C, tempering at 640 ° C and air cooling. SHADE HEAT TREATMENT Rm MPa INV AT SOFTENED 535 REF 2 SOFTENED 544 REF 1 SOFTENED 544 INV AT TREATY 858 REF 2 TREATY 967 REF 1 TREATY 899 Rp0.2 MPa AT% Z% HARDNESS HRB / HRC 282 29 82 296 29.2 64.1 82.3 HRB 280 28.6 60.6 80.6 HRB 737 14 51 837 12 52.6 29.1 HRC 754 15.5 55.8 27.3 HRC TABLE 1

Les tests ont montré que les aciers dits "traités" s'usinent mieux que les aciers adoucis.Tests have shown that so-called "treated" steels work better than softened steels.

Dans un autre exemple d'application, un acier martensitique selon l'invention et dont la composition pondérale est la seule suivante : C Si Mn Cr Mo ACIER B 0,196 0,444 0,555 12,10 0,073 9 P N Ca O Ca/O AcierB 0,0263 0,019 0,053 41.10⁻⁴ 99.10⁻⁴ 0,41 In another example of application, a martensitic steel according to the invention and the only weight composition of which is as follows: VS Yes Mn Cr Mo STEEL B 0.196 0.444 0.555 12.10 0.073 9 P NOT It O Ca / O SteelB 0.0263 0.019 0.053 41.10⁻⁴ 99.10⁻⁴ 0.41

Dans cet exemple, l'acier B contient, à titre résiduel, moins de 0,5% de nickel et moins de 0,2% de cuivre.In this example, steel B contains, on a residual basis, less than 0.5% of nickel and less than 0.2% of copper.

Cet acier a été comparé à un acier standard de référence ne contenant pas dans sa composition d'oxydes malléables et dont la composition est la suivante : C Si Mn Ni Cr Mo REF 3 0,214 0,344 0,564 0,354 12,32 0,097 Cu S P N Ca O Ca/O REF 3 0,106 0,261 0,017 0,054 45.10⁻⁴ This steel was compared to a standard reference steel which does not contain malleable oxides in its composition and whose composition is as follows: VS Yes Mn Or Cr Mo REF 3 0.214 0.344 0.564 0.354 12.32 0.097 Cu S P NOT It O Ca / O REF 3 0.106 0.261 0.017 0.054 45.10⁻⁴

On remarque sur le tableau 2 ci-dessous que les caractéristiques mécaniques comparées entre l'acier de référence 3 et l'acier B selon l'invention ne présentent pas de différences significatives tant dans le cas d'un état adouci que traité. REF. 3 ACIER B ADOUCI TRAITE ADOUCI TRAITE Rm(MPa) 559 803 566 787 Rp0,2(MPa) 418 636 408 600 A% 29 18,7 29 19 Z% 67,5 60,5 67 63 TABLEAU 2 It is noted in table 2 below that the mechanical characteristics compared between the reference steel 3 and the steel B according to the invention do not have no significant differences both in the case of a milder state than a treated one. REF. 3 STEEL B SOFTENED TREATY SOFTENED TREATY Rm (MPa) 559 803 566 787 Rp0.2 (MPa) 418 636 408 600 AT% 29 18.7 29 19 Z% 67.5 60.5 67 63 TABLE 2

Le tableau 3 ci-dessous présente des valeurs caractéristiques des tests d'usinage et montre que les aciers traités selon l'invention donnent un gain d'usinabilité de 25 à 30%. ETAT METALLURGIQUE TRAITE ADOUCI test : Vb 30/0,3 (m/mn) Vb 15/0,15 (m/mn) Vb 30/0,3 (m/mn) Vb 15/0,15 (m/mn) Acier réf 1 195 250 - - Acier réf 2 150 205 - - Acier réf 3 230 250 200 220 Acier A 250 - - - Acier B 250 290 - - TABLEAU 3 Table 3 below presents characteristic values of the machining tests and shows that the steels treated according to the invention give a machinability gain of 25 to 30%. METALLURGICAL CONDITION TREATY SOFTENED test: Vb 30 / 0.3 (m / min) Vb 15 / 0.15 (m / min) Vb 30 / 0.3 (m / min) Vb 15 / 0.15 (m / min) Steel ref 1 195 250 - - Steel ref 2 150 205 - - Steel ref 3 230 250 200 220 Steel A 250 - - - Steel B 250 290 - - TABLE 3

Dans un troisième exemple d'application deux aciers martensitiques C et D selon l'invention dont les compositions sont les suivantes : C Si Mn Ni Cr Mo Acier C 0,018 0,443 0,825 4,517 15,2 0,005 Acier D 0,012 0,448 0,818 3,739 15,37 0,005 Cu P N Nb S.10⁻⁴ Ca.10⁻⁴ 0.10⁻⁴ 3,189 0,01 0,018 0,202 110 65 132 3,236 0,01 0,021 0,192 233 70 157 In a third example of application, two martensitic steels C and D according to the invention, the compositions of which are as follows: VS Yes Mn Or Cr Mo Steel C 0.018 0.443 0.825 4.517 15.2 0.005 Steel D 0.012 0.448 0.818 3,739 15.37 0.005 Cu P NOT Nb S.10⁻⁴ Ca.10⁻⁴ 0.10⁻⁴ 3.189 0.01 0.018 0.202 110 65 132 3,236 0.01 0.021 0.192 233 70 157

Les aciers C et D ont été comparés à des aciers de référence, ne contenant pas d'oxydes malléables et dont les compositions pondérales sont les suivantes: C Si Mn Ni Cr Mo Ref. 4 0,011 0,45 0,815 4,548 15,26 0,006 Ref. 5 0,013 0,405 0,878 4,509 15,26 0,006 Cu P N Nb S.10⁻⁴ Ca.10⁻⁴ 0.10⁻⁴ 3,245 0,011 0,017 0,182 270 <5 138 3,228 0,011 0,016 0,202 110 <5 48 Steels C and D were compared with reference steels, not containing malleable oxides and whose weight compositions are as follows: VS Yes Mn Or Cr Mo Ref. 4 0.011 0.45 0.815 4.548 15.26 0.006 Ref. 5 0.013 0.405 0.878 4.509 15.26 0.006 Cu P NOT Nb S.10⁻⁴ Ca.10⁻⁴ 0.10⁻⁴ 3.245 0.011 0.017 0.182 270 <5 138 3,228 0.011 0.016 0.202 110 <5 48

Ces aciers de référence contiennent en leur composition du cuivre et du nickel et font partie des nuances à durcissement structural.These reference steels contain copper and nickel in their composition and are among the grades with structural hardening.

Trois états métallurgiques correspondants à des traitements thermiques différents, sont couramment rencontrés :

  • l'état trempé : trempe huile à 1050°C, puis revenu à 250°C. Rm 1000 MPa,
  • l'état vieilli, dans lequel le métal a sa dureté maximale : trempe 1050°C, puis revenu vers 450°C. Rm 1400 MPa
  • l'état adouci : trempe 1050°C, revenu à 760°C pendant 4 heures, deuxième revenu vers 620°C. Rm 900 MPa
Three metallurgical states corresponding to different heat treatments are commonly encountered:
  • quenched state: quenched oil at 1050 ° C, then returned to 250 ° C. Rm 1000 MPa,
  • the aged state, in which the metal has its maximum hardness: quenching 1050 ° C, then returned to 450 ° C. Rm 1400 MPa
  • the softened state: quenching 1050 ° C, tempering at 760 ° C for 4 hours, second tempering around 620 ° C. Rm 900 MPa

La particularité de ce type de nuances est qu'elle ne subit pas de variations dimensionnelles suite aux traitements thermiques. Elle peut donc être usinée, puis vieillie.The peculiarity of this type of shade is that it does not undergo dimensional variations following heat treatments. It can therefore be machined, then aged.

L'acier D selon l'invention a été traité par usinage à l'état trempé. C'est à dire qu'il a subit une trempe à 1050°C dans de l'huile. Il est apparu, comme représenté sur les courbes de la figure 2, que la présence d'oxydes malléables augmentait bien l'usinabilité ce qui se constate sur les courbes par la diminution de l'usure des outils. Cette usure passe en effet de 0,15 mm après 15 mn d'usinage à une vitesse de 190 m/mn, une avance de 0,15 mm/tour, une profondeur de passe de 1,5 mm pour l'acier référence 4, à une usure de 0,125 mm pour l'acier D.The steel D according to the invention was treated by machining in the quenched state. This means that it has been quenched at 1050 ° C in oil. It appeared, as shown on the curves of FIG. 2, that the presence of malleable oxides did indeed increase the machinability which is observed on the curves by the reduction in the wear of the tools. This wear actually goes from 0.15 mm after 15 minutes of machining at a speed of 190 m / min, an advance of 0.15 mm / revolution, a depth of cut of 1.5 mm for steel reference 4 , at a wear of 0.125 mm for steel D.

L'acier D selon l'invention a permis d'obtenir à l'état adouci une vitesse de coupe de 240 m/mn alors que l'acier de référence 5 a permis une vitesse de coupe de 210 m/mn. Le gain enregistré est de 20%.Steel D according to the invention made it possible to obtain in the softened state a cutting speed of 240 m / min while reference steel 5 allowed a cutting speed of 210 m / min. The gain recorded is 20%.

Il est bien mis en évidence avec ces différents exemples d'application, que les aciers martensitiques contenant dans leur composition des oxydes malléables ont une usinabilité améliorée, les oxydes ne détériorant pas les autres caractéristiques desdits aciers.It is well highlighted with these different application examples, that martensitic steels containing in their composition malleable oxides have improved machinability, the oxides not deteriorating the other characteristics of said steels.

Claims (8)

Acier inoxydable martensitique à usinabilité améliorée, caractérisé en ce que sa composition pondérale est la suivante : - carbone inférieur à 1,2% - silicium inférieur ou égal à 2% - manganèse inférieur ou égal à 2% - chrome : 10,5<Cr<19% - soufre inférieur ou égal à 0,55% - calcium supérieur à 32.10⁻⁴% - Oxygène supérieur à 70.10⁻⁴%    le rapport de la teneur en calcium et en oxygène Ca/O étant 0,2<Ca/O<0,6, ledit acier étant soumis à au moins un traitement thermique de trempe pour lui conférer une structure martensitique.Martensitic stainless steel with improved machinability, characterized in that its weight composition is as follows: - carbon less than 1.2% - silicon less than or equal to 2% - manganese less than or equal to 2% - chromium: 10.5 <Cr <19% - sulfur less than or equal to 0.55% - calcium greater than 32.10⁻⁴% - Oxygen higher than 70.10⁻⁴% the ratio of the calcium and oxygen content Ca / O being 0.2 <Ca / O <0.6, said steel being subjected to at least one quenching heat treatment to give it a martensitic structure. Acier selon la revendication 1, caractérisé en ce qu'il comprend du soufre dans une proportion inférieure ou égale à 0,035%.Steel according to claim 1, characterized in that it comprises sulfur in a proportion less than or equal to 0.035%. Acier selon la revendication 1, caractérisée en ce qu'il comprend du soufre dans une proportion 0,15%<S<0,45%, ledit acier étant resulfuré.Steel according to claim 1, characterized in that it comprises sulfur in a proportion 0.15% <S <0.45%, said steel being resulfurized. Acier selon la revendication 1 à 3, caractérisé en ce qu'il comprend, en outre, du nickel dans une proportion inférieure ou égale à 6%.Steel according to claim 1 to 3, characterized in that it further comprises nickel in a proportion less than or equal to 6%. Acier selon l'une des revendications 1 à 4, caractérisé en ce qu'il comprend, en outre, du molybdène dans une proportion inférieure ou égale à 3%.Steel according to one of claims 1 to 4, characterized in that it further comprises molybdenum in a proportion less than or equal to 3%. Acier selon l'une des revendications 1 à 3, caractérisé en ce qu'il comprend, en outre, dans sa composition pondérale des éléments choisis parmi le tungstène, le cobalt, le niobium, le titane, le tantale, le zirconium, le vanadium, le molybdène dans les proportions pondérales suivantes : - tungstène inférieur ou égal à 4% - cobalt inférieur ou égal à 4,5% - niobium inférieur ou égal à 1% - titane inférieur ou égal à 1% - tantale inférieur ou égal à 1% - zirconium inférieur ou égal à 1% - vanadium inférieur ou égal à 1% - molybdène inférieur ou égale à 3%. Steel according to one of Claims 1 to 3, characterized in that it also comprises, in its weight composition, elements chosen from tungsten, cobalt, niobium, titanium, tantalum, zirconium, vanadium , molybdenum in the following weight proportions: - tungsten less than or equal to 4% - cobalt less than or equal to 4.5% - niobium less than or equal to 1% - titanium less than or equal to 1% - tantalum less than or equal to 1% - zirconium less than or equal to 1% - vanadium less than or equal to 1% - molybdenum less than or equal to 3%. Acier selon la revendication 6, caractérisé en ce qu'il comprend du nickel dans une proportion 2%<Ni<6% et du cuivre dans une proportion 1%<Cu<5%.Steel according to claim 6, characterized in that it comprises nickel in a proportion 2% <Ni <6% and copper in a proportion 1% <Cu <5%. Acier selon l'une des revendications 1 à 7, caractérisé en ce qu'il contient des inclusions de silicoaluminate de chaux de type anorthide et/ou pseudo-wollastonite et/ou géhlénite.Steel according to one of claims 1 to 7, characterized in that it contains inclusions of lime silicoaluminate of the anorthide and / or pseudo-wollastonite and / or gehenite type.
EP94401246A 1993-06-14 1994-06-06 Martensitic stainless steel with improved machinability Expired - Lifetime EP0629714B1 (en)

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1999036584A1 (en) * 1998-01-16 1999-07-22 Crs Holdings, Inc. Free-machining martensitic stainless steel
WO2000053821A1 (en) * 1999-03-08 2000-09-14 Crs Holdings, Inc. An enhanced machinability precipitation-hardenable stainless steel for critical applications
EP1314792A1 (en) * 2001-11-26 2003-05-28 Usinor Ferritic stainless steel containing sulfur for ferromagnetic parts
US20180274081A1 (en) * 2015-07-08 2018-09-27 Safran Aircraft Engines Part coated with a coating for protection against cmas

Families Citing this family (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2720410B1 (en) * 1994-05-31 1996-06-28 Ugine Savoie Sa Ferritic stainless steel with improved machinability.
FR2740783B1 (en) * 1995-11-03 1998-03-06 Ugine Savoie Sa FERRITIC STAINLESS STEEL USABLE FOR THE PRODUCTION OF STEEL WOOL
JP3284092B2 (en) * 1997-12-05 2002-05-20 理研ダイヤモンド工業株式会社 Cutting and crushing cutter
EP1099772B1 (en) * 1999-05-18 2004-12-29 Sumitomo Metal Industries, Ltd. Martensite stainless steel for seamless steel tube
FR2811683B1 (en) * 2000-07-12 2002-08-30 Ugine Savoie Imphy FERRITIC STAINLESS STEEL FOR USE IN FERROMAGNETIC PARTS
US6461452B1 (en) * 2001-05-16 2002-10-08 Crs Holdings, Inc. Free-machining, martensitic, precipitation-hardenable stainless steel
FR2933990B1 (en) * 2008-07-15 2010-08-13 Aubert & Duval Sa LOW-COBALT HARDENED CURED MARTENSITIC STEEL, METHOD FOR MANUFACTURING A WORKPIECE THEREFROM, AND PIECE THUS OBTAINED
DE102009030489A1 (en) * 2009-06-24 2010-12-30 Thyssenkrupp Nirosta Gmbh A method of producing a hot press hardened component, using a steel product for the manufacture of a hot press hardened component, and hot press hardened component
UA111115C2 (en) 2012-04-02 2016-03-25 Ейкей Стіл Пропертіс, Інк. cost effective ferritic stainless steel
RU2507297C1 (en) * 2012-10-05 2014-02-20 Леонид Михайлович Клейнер Steels with lath martensite structure
EP2728028B1 (en) 2012-11-02 2018-04-04 The Swatch Group Research and Development Ltd. Edelstahllegierung ohne Nickel
CN102965580B (en) * 2012-11-27 2016-01-20 黄山市新光不锈钢材料制品有限公司 A kind of high carbon martensite stainless steel
CN102943211B (en) * 2012-11-27 2015-12-23 黄山市新光不锈钢材料制品有限公司 A kind of manufacture method of high carbon martensite Stainless Steel Band
US9181597B1 (en) 2013-04-23 2015-11-10 U.S. Department Of Energy Creep resistant high temperature martensitic steel
US9556503B1 (en) 2013-04-23 2017-01-31 U.S. Department Of Energy Creep resistant high temperature martensitic steel
CN103725994B (en) * 2013-12-16 2016-06-08 泰州俊宇不锈钢材料有限公司 A kind of High-performance martensitic steel wire and manufacture method thereof
RU2557850C1 (en) * 2014-10-21 2015-07-27 Юлия Алексеевна Щепочкина Steel
DE102016219350A1 (en) * 2016-10-06 2018-04-12 Kjellberg-Stiftung Nozzle cap, arc plasma torch with this nozzle cap and use of the arc plasma torch
RU2650945C1 (en) * 2017-12-19 2018-04-18 Юлия Алексеевна Щепочкина Steel
RU2672165C1 (en) * 2018-07-20 2018-11-12 Юлия Алексеевна Щепочкина Steel

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2445388A1 (en) * 1978-12-25 1980-07-25 Daido Steel Co Ltd Free cutting steel for use on automatic lathes - contains manganese, sulphur and tellurium, where manganese sulphide inclusions have specific size and shape
FR2456785A1 (en) * 1979-05-17 1980-12-12 Daido Steel Co Ltd DECOLLETING STEEL CONTAINING DETERMINED INCLUSIONS AND A PROCESS FOR THE PREPARATION THEREOF
EP0403332A1 (en) * 1989-06-16 1990-12-19 Ugine Savoie Resulfurized austenitic stainless steel with improved machinability

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3690869A (en) * 1970-08-26 1972-09-12 Yakov Mikhailovich Potak Martensite stainless steel
JPS55122858A (en) * 1979-03-13 1980-09-20 Daido Steel Co Ltd High carbon high manganese steel with high machinability
JPS5970748A (en) * 1982-10-12 1984-04-21 Kawasaki Steel Corp Hot-rolled platelike material of low carbon martensitic stainless steel with superior toughness for disk brake for motorcycle
JPH0215143A (en) * 1988-06-30 1990-01-18 Aichi Steel Works Ltd Soft magnetic stainless steel for cold forging
JPH02104633A (en) * 1989-07-28 1990-04-17 Daido Steel Co Ltd High strength and non-magnetic high manganese steel
FR2690169B1 (en) * 1992-04-17 1994-09-23 Ugine Savoie Sa Austenitic stainless steel with high machinability and improved cold deformation.

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2445388A1 (en) * 1978-12-25 1980-07-25 Daido Steel Co Ltd Free cutting steel for use on automatic lathes - contains manganese, sulphur and tellurium, where manganese sulphide inclusions have specific size and shape
FR2456785A1 (en) * 1979-05-17 1980-12-12 Daido Steel Co Ltd DECOLLETING STEEL CONTAINING DETERMINED INCLUSIONS AND A PROCESS FOR THE PREPARATION THEREOF
EP0403332A1 (en) * 1989-06-16 1990-12-19 Ugine Savoie Resulfurized austenitic stainless steel with improved machinability
FR2648477A1 (en) * 1989-06-16 1990-12-21 Ugine Savoie Sa STAINLESS STEEL AUSTENIAC RESULFURE WITH IMPROVED MACHINABILITY

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
HOUDREMONT: "Handbuch der Sonderstahlkunde, vol.2, pages 1279-1290", 1956, SPRINGER-VERLAG, BERLIN/GöTTINGEN/HEIDELBERG *

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1999036584A1 (en) * 1998-01-16 1999-07-22 Crs Holdings, Inc. Free-machining martensitic stainless steel
US6146475A (en) * 1998-01-16 2000-11-14 Crs Holdings, Inc. Free-machining martensitic stainless steel
WO2000053821A1 (en) * 1999-03-08 2000-09-14 Crs Holdings, Inc. An enhanced machinability precipitation-hardenable stainless steel for critical applications
KR100437960B1 (en) * 1999-03-08 2004-07-01 씨알에스 홀딩즈 인코포레이티드 An enhanced machinability precipitation-hardenable stainless steel for critical applications
CZ303180B6 (en) * 1999-03-08 2012-05-16 Crs Holdings, Inc. Stainless steel for critical applications hardenable by precipitation and exhibiting improved machining characteristics
EP1314792A1 (en) * 2001-11-26 2003-05-28 Usinor Ferritic stainless steel containing sulfur for ferromagnetic parts
FR2832734A1 (en) * 2001-11-26 2003-05-30 Usinor SULFUR FERRITIC STAINLESS STEEL, USEFUL FOR FERROMAGNETIC PARTS
US6921511B2 (en) 2001-11-26 2005-07-26 Ugitech Sulphur-containing ferritic stainless steel that can be used for ferromagnetic parts
US20180274081A1 (en) * 2015-07-08 2018-09-27 Safran Aircraft Engines Part coated with a coating for protection against cmas
US10941083B2 (en) * 2015-07-08 2021-03-09 Safran Aircraft Engines Part coated with a coating for protection against CMAS

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FR2706489B1 (en) 1995-09-01
CZ292392B6 (en) 2003-09-17
FI942801A (en) 1994-12-15
UA26151C2 (en) 1999-06-07
DE69423930T2 (en) 2000-08-17
CA2125732C (en) 2000-08-01
FI106267B (en) 2000-12-29
PT629714E (en) 2000-09-29
IL109919A (en) 1998-02-22
NO942168D0 (en) 1994-06-10
FI942801A0 (en) 1994-06-13
CZ141994A3 (en) 1995-08-16
NO942168L (en) 1994-12-15
JPH07150308A (en) 1995-06-13
CA2125732A1 (en) 1994-12-15
JP3398772B2 (en) 2003-04-21
DK0629714T3 (en) 2000-07-17
RU94020719A (en) 1996-06-27
US5427635A (en) 1995-06-27
SI0629714T1 (en) 2000-08-31
PL179128B1 (en) 2000-07-31
IL109919A0 (en) 1994-10-07
KR100338886B1 (en) 2002-11-29
KR950000912A (en) 1995-01-03
FR2706489A1 (en) 1994-12-23
TW304985B (en) 1997-05-11
PL303831A1 (en) 1995-01-09
SG48134A1 (en) 1998-04-17
GR3033773T3 (en) 2000-10-31
EG20378A (en) 1999-02-28
DE69423930D1 (en) 2000-05-18
ES2145109T3 (en) 2000-07-01
TR28472A (en) 1996-07-24
EP0629714B1 (en) 2000-04-12
RU2080410C1 (en) 1997-05-27
RO115276B1 (en) 1999-12-30
ATE191753T1 (en) 2000-04-15
NO303180B1 (en) 1998-06-08

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