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EP0237721B1 - Aluminium-killed heat-treatable steel - Google Patents

Aluminium-killed heat-treatable steel Download PDF

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Publication number
EP0237721B1
EP0237721B1 EP87100763A EP87100763A EP0237721B1 EP 0237721 B1 EP0237721 B1 EP 0237721B1 EP 87100763 A EP87100763 A EP 87100763A EP 87100763 A EP87100763 A EP 87100763A EP 0237721 B1 EP0237721 B1 EP 0237721B1
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EP
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Prior art keywords
zirconium
aluminium
treatable steel
steel
heat
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EP87100763A
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German (de)
French (fr)
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EP0237721A2 (en
EP0237721A3 (en
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Cestmir Dr.-Ing. Lang
Lutz Dr.-Ing. Meyer
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Thyssen Stahl AG
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Thyssen Stahl AG
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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
    • C22C38/22—Ferrous alloys, e.g. steel alloys containing chromium with molybdenum or tungsten
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/14—Ferrous alloys, e.g. steel alloys containing titanium or zirconium
    • 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
    • C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium

Definitions

  • the invention relates to an aluminum-hardened tempering steel with good hardenability.
  • the hardening depth is a measure of the hardenability of steels. It is usually defined as the distance from the surface at which 50% of the structure still consists of martensite.
  • unalloyed and alloyed tempering steels require a coarse austenite grain (ASTM grain number 6 or less) when austenitizing before hardening.
  • the coarse austenite grain has hitherto been limited to a max. 0.005% with usual and to max. 0.010% reached at elevated austenitizing temperatures.
  • Tempering steels with good hardenability have not hitherto been able to be produced by continuous casting because, for reasons of castability and product properties, minimum aluminum contents of the order of more than 0.010% are prescribed in the production of continuous castings. This is particularly disadvantageous because of the increased use of the economical continuous casting process in the steel industry.
  • austenitizing temperatures in the range between 950 and 1050 ° C would be required to achieve a coarse-grained austenite. Austenitizing temperatures of this kind are unacceptable, both for reasons of energy costs and due to technical limitations and scaling.
  • the hardenability loss of tempered tempered steels can be compensated for by adding alloying elements such as manganese or chromium.
  • alloying elements such as manganese or chromium.
  • these measures can only be carried out with restrictions.
  • the individual steel grades are to be delivered according to certain analysis instructions. Deviations from these regulations will not be tolerated.
  • the invention has for its object to reduce the adverse influence of aluminum on the hardenability of aluminum-hardened tempering steels with justifiable and economical means and to propose an aluminum-hardened hardening steel with improved hardenability, which can be inexpensively produced by the continuous casting process.
  • the addition of the nitrogen-affine element zirconium prevents the aluminum nitride precipitation in the steel, which would lead to a fine austenite grain.
  • zirconium By adding zirconium, however, coarse nitrides are formed when the steel solidifies.
  • a coarse austenite grain ASTM: 2 to 6
  • ASTM Standard austenitizing temperatures of approximately 800 to 860 ° C. and holding times over 10 minutes, corresponds to that of a silicon-calmed steel.
  • a zirconium additive leads to excellent hardenability regardless of the carbon content.
  • the carbon content is preferably 0.41 to 1.0%, the manganese content 0.20 to 2.0%, the silicon content to 0.5%, the nitrogen content 0.002 to 0.0065% Aluminum content 0.015 to 0.08% and the zirconium content 0.015 to 0.065%. But even with even lower manganese contents of 0.20 to 1.2% or 0.40 to 1.0%, the hardened steel has excellent hardenability.
  • the tempering steel according to the invention can also add chromium, nickel, molybdenum individually or to contain several, namely 0.05 to 3.5%, in particular 0.05 to 1.5% chromium and / or nickel and / or 0.05 to 0.5% molybdenum.
  • the steel In order not to impair the good hardenability of the steel according to the invention, however, the steel must not contain any alloying elements, such as niobium or titanium, which would lead to a fine grain in the austenite and, moreover, via germs in the structure, the austenite conversion in the ferrite / pearlite stage in the would accelerate hardening.
  • alloying elements such as niobium or titanium
  • the particular advantage of the heat-treatable steel according to the invention can be seen in the fact that the hardenability is adjusted to the level of the silicon-stabilized steels without a significant change in the analysis specification and without impairing the mechanical properties, and the use of the economical continuous casting process is made possible.
  • Another advantage of the aluminum calming and addition of zirconium in the tempering steel according to the invention is the assurance of aging resistance. Conventional tempering steels have free nitrogen and are therefore susceptible to aging.
  • the steel is preferably produced by continuous casting.
  • Steels A to M were melted in an oxygen inflation process.
  • the chemical composition and austenite grain size, determined as quenching grain size according to DIN 50601, of the steels are shown in Table 1.
  • Steels A to H fall under the invention.
  • Steels I and J, which have no addition of zirconium, and steels K and L, which have an Al content below 0.010%, and steel M, which shows a Zr / N ratio of less than 7, are not included The invention.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Treatment Of Steel In Its Molten State (AREA)
  • Heat Treatment Of Articles (AREA)
  • Heat Treatment Of Steel (AREA)
  • Lubricants (AREA)
  • Solid-Phase Diffusion Into Metallic Material Surfaces (AREA)
  • Continuous Casting (AREA)
  • Laminated Bodies (AREA)
  • Forms Removed On Construction Sites Or Auxiliary Members Thereof (AREA)

Abstract

A continuously cast steel consisting of 0.32 to 1.0% carbon 0.20 to 3.0% manganese, up to 2.0% silicon, max. 0.05% phosphorus, max. 0.05% sulphur, 0.002 to 0.008% nitrogen, 0.015 to 0.08% zirconium, 0.010 to 0.10% aluminium, up to 3.5% chromium, up to 3.5% nickel and up to 0.5% molybdenum rest iron and unavoidable impurities, wherein the zirconium: nitrogen ratio being 7:1 to 10:1 and the austenite grain size being ASTM 6 or a smaller grain size number.

Description

Die Erfindung betrifft einen aluminiumberuhigten Vergütungsstahl mit guter Härtbarkeit. Für die Härtbarkeit von Stählen ist die Einhärtungstiefe ein Maß. Sie wird in der Regel definiert als der Abstand von der Oberfläche, bei der noch 50 % des Gefüges aus Martensit besteht.The invention relates to an aluminum-hardened tempering steel with good hardenability. The hardening depth is a measure of the hardenability of steels. It is usually defined as the distance from the surface at which 50% of the structure still consists of martensite.

Unlegierte und legierte Vergütungsstähle verlangen aus Gründen der Härtbarkeit ein grobes Austenitkorn (ASTM-Kornzahl 6 oder kleiner) beim Austenitisieren vor dem Härten. Das grobe Austenitkorn wird bisher durch eine Begrenzung des Aluminium-Gehaltes auf max. 0,005 % bei üblichen und auf max. 0,010 % bei erhöhten Austenitisierungstemperaturen erreicht.For reasons of hardenability, unalloyed and alloyed tempering steels require a coarse austenite grain (ASTM grain number 6 or less) when austenitizing before hardening. The coarse austenite grain has hitherto been limited to a max. 0.005% with usual and to max. 0.010% reached at elevated austenitizing temperatures.

Vergütungsstähle mit guter Härtbarkeit können bisher nicht durch Stranggießen hergestellt werden, weil bei der Stranggußherstellung aus Gründen der Vergießbarkeit und der Produkteigenschaften Mindestgehalte an Aluminium in der Größenordnung von mehr als 0,010 % vorgeschrieben sind. Wegen des vermehrten Einsatzes des wirtschaftlichen Stranggießverfahrens in der Stahlindustrie ist dies besonders nachteilig.Tempering steels with good hardenability have not hitherto been able to be produced by continuous casting because, for reasons of castability and product properties, minimum aluminum contents of the order of more than 0.010% are prescribed in the production of continuous castings. This is particularly disadvantageous because of the increased use of the economical continuous casting process in the steel industry.

Bei Anwendung einer Vollberuhigung solcher Stähle mit Aluminium würden die im Verlauf der Austenitisierung gebildeten oder bereits schon vorhandenen Aluminiumnitride eine Kornfeinung durch Keimbildung oder durch Wachstumsbehinderung des Austenitkorns bewirken. Je nach Aluminium- bzw. Stickstoff-Gehalten würde in diesen Stählen bei üblichen Austenitisierungstemperaturen von ca. 800 bis 860 °C ein feines Austenitkorn gebildet, welches die Härtbarkeit stark herabsetzt.If such steels with aluminum were completely calmed down, the aluminum nitrides formed or already present in the course of the austenitization would cause grain refinement by nucleation or by hindrance to growth of the austenite grain. Depending on the aluminum or nitrogen content, a fine austenite grain would be formed in these steels at usual austenitizing temperatures of approx. 800 to 860 ° C, which greatly reduces the hardenability.

Bei Stählen mit Aluminium-Gehalten von mehr als 0,015 %, wie sie bei einer Aluminium-Vollberuhigung vorliegen, würden zum Erreichen eines grobkörnigen Austenits Austenitisierungstemperaturen in der Größenordnung zwischen 950 und 1050 °C benötigt werden. Sowohl aus Gründen der Energiekosten als auch aufgrund anlagentechnischer Grenzen und wegen stärkerer Verzunderung sind solche Austenitisierungstemperaturen nicht vertretbar.In the case of steels with aluminum contents of more than 0.015%, as is the case with full aluminum sedation, austenitizing temperatures in the range between 950 and 1050 ° C would be required to achieve a coarse-grained austenite. Austenitizing temperatures of this kind are unacceptable, both for reasons of energy costs and due to technical limitations and scaling.

Der Härtbarkeitsverlust von aluminiumberuhigten Vergütungsstählen kann zwar durch Zugabe von Legierungselementen, wie Mangan oder Chrom, ausgeglichen werden. Diese Maßnahmen sind jedoch nur mit Einschränkungen durchführbar. Abgesehen von negativen Effekten der genannten Elemente, insbesondere Verschlechterung der Kaltumformbarkeit, sind die einzelnen Stahlgüten nach bestimmten Analysenvorschriften zu liefern. Abweichungen von diesen Vorschriften werden nicht toleriert.The hardenability loss of tempered tempered steels can be compensated for by adding alloying elements such as manganese or chromium. However, these measures can only be carried out with restrictions. Apart from the negative effects of the elements mentioned, in particular deterioration of the cold formability, the individual steel grades are to be delivered according to certain analysis instructions. Deviations from these regulations will not be tolerated.

Der Erfindung liegt die Aufgabe zugrunde, den nachteiligen Einfluß des Aluminiums auf die Härtbarkeit von aluminiumberuhigten Vergütungsstählen mit vertretbaren und wirtschaftlichen Mitteln abzubauen und einen aluminiumberuhigten Vergütungsstahl mit verbesserter Härtbarkeit vorzuschlagen, der nach dem Stranggießverfahren preiswert hergestellt werden kann.The invention has for its object to reduce the adverse influence of aluminum on the hardenability of aluminum-hardened tempering steels with justifiable and economical means and to propose an aluminum-hardened hardening steel with improved hardenability, which can be inexpensively produced by the continuous casting process.

Diese Aufgabe wird bei einem aluminiumberuhigten Vergütungsstahl mit

  • 0,32 bis 1,0 % Kohlenstoff,
  • 0,20 bis 3,0 % Mangan,
  • bis 2,0 % Silizium,
  • max. 0,05 % Phosphor,
  • max. 0,05 % Schwefel,
  • 0,002 bis 0,008 % Stickstoff,
  • 0,010 bis 0,10 % Aluminium,
  • wahlweise einzeln oder zu mehreren
  • 0,05 bis 3,5 % Chrom
  • 0,05 bis 3,5 % Nickel
  • 0,05 bis 0,5 % Molybdän
  • Rest Eisen und unvermeidbare Verunreinigungen,
  • erfindungsgemäß dadurch gelöst, daß dem Stahl zusätzlich 0,015 bis 0,08 % Zirkonium zugesetzt wird, wobei das Verhältnis von Zirkonium : Stickstoff = 7 : 1 bis 10 : 1 beträgt, und daß die Austenit-Korngröße nach ASTM Nr. 6 oder eine kleinere Kornzahl ist. (Die Bestimmung der Austenit-Korngröße nach ASTM (American Society for Testing and Materials) erfolgt nach ASTM-Norm E 112, siehe auch Stahl-Eisen-Prüfblatt 1510)
This task is performed with an aluminum-calmed tempered steel
  • 0.32 to 1.0% carbon,
  • 0.20 to 3.0% manganese,
  • up to 2.0% silicon,
  • Max. 0.05% phosphorus,
  • Max. 0.05% sulfur,
  • 0.002 to 0.008% nitrogen,
  • 0.010 to 0.10% aluminum,
  • either individually or in groups
  • 0.05 to 3.5% chromium
  • 0.05 to 3.5% nickel
  • 0.05 to 0.5% molybdenum
  • Rest of iron and unavoidable impurities,
  • solved according to the invention by additionally adding 0.015 to 0.08% zirconium to the steel, the ratio of zirconium: nitrogen = 7: 1 to 10: 1, and in that the austenite grain size according to ASTM No. 6 or a smaller grain number is. (The austenite grain size is determined according to ASTM (American Society for Testing and Materials) according to ASTM standard E 112, see also steel-iron test sheet 1510)

Durch die Zugabe des stickstoff-affinen Elementes Zirkonium wird die Aluminiumnitrid-Ausscheidung im Stahl verhindert, die zu einem feinen Austenitkorn führen würde. Durch die Zugabe von Zirkonium werden dagegen bereits bei der Erstarrung des Stahles grobe Nitride gebildet. Überraschenderweise hat sich gezeigt, daß bei dem erfindungsgemäßen Verhältnis Zirkonium : Stickstoff = 7 : 1 bis 10 : 1 bei üblichen Austenitisierungstemperaturen von ewa 800 bis 860 °C und Haltezeiten über 10 Minuten ein grobes Austenitkorn (ASTM: 2 bis 6) erzielt wird, das dem eines siliziumberuhigten Stahls entspricht. Dabei führt ein Zirkonium-Zusatz unabhängig vom Kohlenstoff-Gehalt zu einer hervorragenden Härtbarkeit.The addition of the nitrogen-affine element zirconium prevents the aluminum nitride precipitation in the steel, which would lead to a fine austenite grain. By adding zirconium, however, coarse nitrides are formed when the steel solidifies. Surprisingly, it has been shown that with the zirconium: nitrogen = 7: 1 to 10: 1 ratio according to the invention, a coarse austenite grain (ASTM: 2 to 6) is achieved at usual austenitizing temperatures of approximately 800 to 860 ° C. and holding times over 10 minutes, corresponds to that of a silicon-calmed steel. A zirconium additive leads to excellent hardenability regardless of the carbon content.

Bevorzugt beträgt der Kohlenstoff-Gehalt 0,41 bis 1,0 %, der Mangan-Gehalt 0,20 bis 2,0 %, der Silizium-Gehalt bis 0,5 %, der Stickstoff-Gehalt 0,002 bis 0,0065 %, der Aluminium-Gehalt 0,015 bis 0,08 % und der Zirkonium-Gehalt 0,015 bis 0,065 %. Aber auch bei noch geringeren Mangan-Gehalten von 0,20 bis 1,2 % bzw. 0,40 bis 1,0 % stellt sich eine hervorragende Härtbarkeit des Vergütungsstahles ein.The carbon content is preferably 0.41 to 1.0%, the manganese content 0.20 to 2.0%, the silicon content to 0.5%, the nitrogen content 0.002 to 0.0065% Aluminum content 0.015 to 0.08% and the zirconium content 0.015 to 0.065%. But even with even lower manganese contents of 0.20 to 1.2% or 0.40 to 1.0%, the hardened steel has excellent hardenability.

Der erfindungsgemäße Vergütungsstahl kann ferner Zusätze von Chrom, Nickel, Molybdän einzeln oder zu mehreren enthalten, und zwar 0,05 bis 3,5 %, insbesondere 0,05 bis 1,5 % Chrom und/oder Nickel und/oder 0,05 bis 0,5 % Molybdän.The tempering steel according to the invention can also add chromium, nickel, molybdenum individually or to contain several, namely 0.05 to 3.5%, in particular 0.05 to 1.5% chromium and / or nickel and / or 0.05 to 0.5% molybdenum.

Um die gute Härtbarkeit des erfindungsgemäßen Stahles nicht zu beeinträchtigen, darf der Stahl jedoch keine Legierungselemente, wie Niob oder Titan, enthalten, die zu einem Feinkorn im Austenit führen würden und außerdem über Keime im Gefüge die Austenitumwandlung in der Ferrit/Perlit-Stufe bei der Härtung beschleunigen würden.In order not to impair the good hardenability of the steel according to the invention, however, the steel must not contain any alloying elements, such as niobium or titanium, which would lead to a fine grain in the austenite and, moreover, via germs in the structure, the austenite conversion in the ferrite / pearlite stage in the Would accelerate hardening.

Es ist bekannt, legierten Baustählen Zirkonium zur Verbesserung des Kaltumformbarkeit zuzusetzen. Der Einfluß eines Zirkoniumzusatzes auf die Nitridbildung und damit der Einfluß auf die Austenitkornvergröberung ist jedoch nicht erwähnt worden (Molybdän-Dienst, Nr. 70, Januar 1971, Seiten 1 bis 8 und Baustähle der Welt, Bd. 11, VEB Deutscher Verlag für Grundstoffindustrie, Leipzig 1968, Seiten 220 bis 231).It is known to add zirconium to alloy structural steels to improve cold formability. The influence of a zirconium additive on the nitride formation and thus the influence on the austenite grain coarsening has not been mentioned (Molybdenum Service, No. 70, January 1971, pages 1 to 8 and structural steels of the world, vol. 11, VEB German publisher for basic material industry, Leipzig 1968, pages 220 to 231).

Bei einer Untersuchung über die Wirkung von Zirkonium auf die mechanischen Eigenschaften unlegierter Baustähle, ähnlich der Stahlsorten St 52-3, wurde nach einer Glühung zwischen 860 bis 900°C (Normalglühung) bei Anwesenheit von Zirkonium eine Abnahme der Menge an ausgeschiedenem Aluminiumnitrid beobachtet, die sich in einer Zunahme der Kornwachstumsneigung äußerte. Proben, die zwischen 860 und 900 °C geglüht wurden, zeigten dementsprechend mit steigendem Zirkonium-Gehalt Anteile von gröberem Feinkorn. Diese Erscheinung ist jedoch wegen der Absenkung der Festigkeitseigenschaften nach dem Normalglühen der Baustähle als negativ angesehen worden. Eine positive Ausnutzung von grobem ZrN im Hinblick auf eine Vergütung konnte im Rahmen dieser Stahlanalyse nicht erfolgen und wurde auch durch die beschriebenen Untersuchungen nicht nahegelegt. (Thyssen Forschung, 2. Jahrgang, 1970, Heft 1, Seiten 35 bis 41)In a study of the effect of zirconium on the mechanical properties of unalloyed structural steels, similar to the steel types St 52-3, a decrease in the amount of aluminum nitride precipitated was observed after annealing between 860 and 900 ° C (normal annealing) in the presence of zirconium manifested itself in an increase in the tendency to grain growth. Samples that were annealed between 860 and 900 ° C accordingly showed parts of coarser fine grain with increasing zirconium content. However, this phenomenon has been considered negative because of the lowering of the strength properties after the normal annealing of the structural steels. A positive utilization of coarse ZrN with regard to a remuneration could not take place in the context of this steel analysis and was also not suggested by the described investigations. (Thyssen Research, 2nd year, 1970, volume 1, pages 35 to 41)

Der besondere Vorteil des erfindungsgemäßen Vergütungsstahls ist darin zu sehen, daß die Härtbarkeit ohne wesentliche Änderung der Analysenvorschrift und ohne Beeinträchtigung der mechanischen Eigenschaften auf das Niveau der siliziumberuhigten Stähle eingestellt und der Einsatz des wirtschaftlichen Stranggießverfahrens ermöglicht wird.The particular advantage of the heat-treatable steel according to the invention can be seen in the fact that the hardenability is adjusted to the level of the silicon-stabilized steels without a significant change in the analysis specification and without impairing the mechanical properties, and the use of the economical continuous casting process is made possible.

Ein weiterer Vorteil der Aluminiumberuhigung und Zusatz von Zirkonium bei dem erfindungsgemäßen Vergütungsstahl ist die Sicherstellung der Alterungsbeständigkeit. Herkömmliche Vergütungsstähle weisen freien Stickstoff auf und sind deshalb alterungsanfällig.Another advantage of the aluminum calming and addition of zirconium in the tempering steel according to the invention is the assurance of aging resistance. Conventional tempering steels have free nitrogen and are therefore susceptible to aging.

Bevorzugt wird der Stahl durch Stranggießen hergestellt.The steel is preferably produced by continuous casting.

Nachfolgend werden die Herstellung des erfindungsgemäßen Vergütungsstahls sowie die dabei ermittelten Werte der Austenitkorngröße anhand von Ausführungsbeispielen näher erläutert. Ferner wird der erfindungsgemäße Stahl mit nicht unter die Erfindung fallenden Vergütungsstählen verglichen.The manufacture of the heat-treatable steel according to the invention and the values of the austenite grain size determined in the process are explained in more detail below using exemplary embodiments. Furthermore, the steel according to the invention is compared with tempering steels not covered by the invention.

In einem Sauerstoffaufblasverfahren wurden die Stähle A bis M erschmolzen. Die chemische Zusammensetzung und Austenitkorngröße, ermittelt als Abschreckkorngröße nach DIN 50601, der Stähle zeigt Tafel 1. Die Stähle A bis H fallen unter die Erfindung. Die Stähle I und J, d ie keinen Zirkoniumzusatz aufweisen, und die Stähle K und L, die einen AI-Gehalt unter 0,010 % aufweisen, und der Stahl M, der ein Zr/N-Verhältnis von kleiner als 7 zeigt, fallen nicht unter die Erfindung.Steels A to M were melted in an oxygen inflation process. The chemical composition and austenite grain size, determined as quenching grain size according to DIN 50601, of the steels are shown in Table 1. Steels A to H fall under the invention. Steels I and J, which have no addition of zirconium, and steels K and L, which have an Al content below 0.010%, and steel M, which shows a Zr / N ratio of less than 7, are not included The invention.

Es wird deutlich, daß von den AI-haltigen, d.h. gut stranggießfähigen Stählen nur diejenigen mit einem Zr-Zusatz und einem Zr/N-Verhältnis zwischen 7 und 10 eine Austenitkorngröße aufweisen, die für eine gute Härtbarkeit erforderlich ist.

Figure imgb0001
It is clear that of the AI-containing, ie, readily castable steels, only those with a Zr addition and a Zr / N ratio between 7 and 10 have an austenite grain size which is necessary for good hardenability.
Figure imgb0001

Claims (7)

1. An aluminium-killed heat-treatable steel having
0.32 to 1.0% carbon, 0.20 to 3.0% manganese,
up to 2.0% silicon,
max. 0.05% phosphorus,
max. 0.05% sulphur,
0.002 to 0.008% nitrogen,
0.010 to 0.10% aluminium,
optionally, individually or in combination,
0.05 to 3.5% chromium,
0.05 to 3.5% nickel,
0.05 to 0.5% molybdenum, residue iron and unavoidable impurities, characterized in that the steel also contains 0.015 to 0.08% zirconium, the zirconium : nitrogen ratio being 7 : 1 to 10 : 1, and the austenite grain size being ASTM 6 or larger (lower ASTM grain number than 6).
2. A heat-treatable steel according to claim 1, characterized in that it contains 0.41 to 1.0% carbon,
0.20 to 2.0% manganese,
up to 0.5% silicon,
0.002 to 0.0065% nitrogen,
0.015 to 0.08% aluminium,
0.015 to 0.065% zirconium, residue iron and unavoidable impurities.
3. A heat treatable steel according to claims 1 or 2, characterized in that the manganese content is 0.20 to 1.20%.
4. A heat treatable steel according to one of-claims 1 to 3, characterized in that the manganese content is 0.40 to 1.0%.
5. A heat treatable steel according to one of claims 1 to 4, characterized in that it also contains
0.05 to 3.5% chromium,
0.05 to 3.5% nickel and
0.05 to 0.5% molybdenum,
separately or in combination.
6. A heat treatable steel according to claim 5, characterized by additions of
0.05 to 1.5% chromium and
0.05 to 1.5% nickel.
7. A heat treatable steel according to one of claims 1 to 6, characterized in that it is continuously cast.
EP87100763A 1986-02-15 1987-01-21 Aluminium-killed heat-treatable steel Expired - Lifetime EP0237721B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT87100763T ATE59065T1 (en) 1986-02-15 1987-01-21 ALUMINUM QUILTED QUALITY STEEL.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3604789 1986-02-15
DE3604789A DE3604789C1 (en) 1986-02-15 1986-02-15 Quenched and tempered steel

Publications (3)

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EP0237721A2 EP0237721A2 (en) 1987-09-23
EP0237721A3 EP0237721A3 (en) 1988-04-20
EP0237721B1 true EP0237721B1 (en) 1990-12-12

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US (1) US4741880A (en)
EP (1) EP0237721B1 (en)
JP (1) JPS62253756A (en)
KR (1) KR930006298B1 (en)
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CN1296509C (en) * 2005-03-10 2007-01-24 武汉钢铁(集团)公司 High strength weldable ageing hardening steel and its production method
DE102013004905A1 (en) 2012-03-23 2013-09-26 Salzgitter Flachstahl Gmbh Zunderarmer tempered steel and process for producing a low-dispersion component of this steel
CN103397269A (en) * 2013-07-01 2013-11-20 安徽三联泵业股份有限公司 Low-cost and high-strength wear-resistant cast steel and preparation method thereof
KR101986187B1 (en) * 2017-11-08 2019-06-05 한국기계연구원 Cast steel
EP3733395A4 (en) 2017-11-16 2021-09-22 Candido Filho, André COMPOSITE MATERIAL, METHOD OF MANUFACTURING THEREOF, USE OF THIS MATERIAL AND ARTICLES WITH THIS MATERIAL
CN112159928B (en) * 2020-09-28 2021-11-12 广东韶钢松山股份有限公司 A kind of bearing steel containing Zr and preparation method thereof

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IN167262B (en) 1990-09-29
DE3604789C1 (en) 1987-08-20
US4741880A (en) 1988-05-03
KR870008046A (en) 1987-09-23
DE3766633D1 (en) 1991-01-24
JPS62253756A (en) 1987-11-05
CN87102168A (en) 1987-09-16
CA1282982C (en) 1991-04-16
AU585694B2 (en) 1989-06-22
AU6871187A (en) 1987-08-20
ES2020201B3 (en) 1991-08-01
EP0237721A2 (en) 1987-09-23
CN1011794B (en) 1991-02-27
EP0237721A3 (en) 1988-04-20
ATE59065T1 (en) 1990-12-15
KR930006298B1 (en) 1993-07-12

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