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EP0291492A1 - Heat resisting zinc base alloy - Google Patents

Heat resisting zinc base alloy Download PDF

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Publication number
EP0291492A1
EP0291492A1 EP88870091A EP88870091A EP0291492A1 EP 0291492 A1 EP0291492 A1 EP 0291492A1 EP 88870091 A EP88870091 A EP 88870091A EP 88870091 A EP88870091 A EP 88870091A EP 0291492 A1 EP0291492 A1 EP 0291492A1
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EP
European Patent Office
Prior art keywords
alloy
zinc
manganese
creep
lithium
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Application number
EP88870091A
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German (de)
French (fr)
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EP0291492B1 (en
Inventor
Gisèle Walmag
Marcel Lamberigts
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Centre de Recherches Metallurgiques CRM ASBL
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Centre de Recherches Metallurgiques CRM ASBL
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Classifications

    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C18/00Alloys based on zinc
    • C22C18/04Alloys based on zinc with aluminium as the next major constituent

Definitions

  • the present invention relates to a zinc-based alloy having improved heat resistance and creep resistance.
  • hot resistance is meant resistance to temperatures of the order of 100 ° C.
  • a zinc alloy intended for casting is known in particular having a breaking load of the order of 400 to 500 MPa. This value was reached by ensuring the alloy an aluminum content of between 5% and 40%, and preferably close to 27%, with additions of copper and magnesium. Its resistance to creep and hot traction (100 ° C) are however modest. In fact, its resistance at 100 ° C. is, under the best casting conditions, of the order of 300 MPa and its creep life at 100 ° C. under a load of 50 MPa is approximately 300 hours.
  • the present invention relates to a zinc-based alloy, intended for casting and having improved creep properties and resistance to heat (100 ° C).
  • the creep life is improved as well as the creep rate and the tensile strength at 100 ° C.
  • composition of the alloy in accordance with the invention results from the unexpected observation made by the applicant, according to which it is possible to improve: - Either the creep resistance of the alloy, by means of additions of lithium and / or manganese; - Either the breaking load of the alloy at 100 ° C, by means of additions of chromium, manganese and / or lithium; - or these two properties simultaneously by judiciously combining the above additions.
  • a zinc alloy containing 5 to 40% aluminum, 0.5% to 5% copper and up to 0.1% magnesium is characterized in that it also has a content between 0.005% and 2.5% in at least one element chosen from the group comprising lithium, manganese and chromium.
  • said zinc alloy contains lithium in a content of between 0.005% and 2.5%, and preferably between 0.01% and 1.
  • the zinc alloy has a manganese content of between 0.005% and 0.2%, and preferably between 0.1% and 0.15%.
  • said zinc alloy contains chromium in a content of between 0.005% and 0.5%.
  • the alloy it is also advantageous for the alloy to contain a combined addition of lithium and manganese, so as to add the improvements in tensile strength and creep resistance at 100 ° C. of this zinc alloy.
  • the zinc alloy according to the invention contains from 0.01% to 1% of lithium and from 0.005% to 0.2% of manganese.
  • a zinc alloy in accordance with the invention contains lithium in a content of between 0.01% and 1.5% and chromium in a content of between 0.005% and 0.5%.
  • the table below illustrates the effect of the additions, in accordance with the invention, which have just been described, on the cold and hot breaking load and on the creep resistance of a zinc-based alloy containing 27% aluminum, 1% copper and 0.02% magnesium.
  • Alloy A is the basic alloy known previously; it has a low creep resistance at 100 ° C and a tensile strength at 100 ° C, expressed by a lifetime under a load of 50 MPa of 300 h and a heat resistance of 295 MPa.
  • Alloy B in accordance with the first variant of the invention shows that an addition of lithium within the limits indicated makes it possible to very significantly raise the values of the creep life and the tensile strength (at 20 ° C. and 100 ° C), while decreasing the creep rate of the alloy.
  • Alloy C corresponding to the second variant also has an increased creep resistance compared to the base alloy.
  • Alloy D which corresponds to the third variant, has significantly higher breaking loads at 20 ° C and 100 ° C than the base alloy, associated with a creep lifetime which is also improved.
  • Alloy E shows that a combined addition of lithium and manganese within the limits indicated, makes it possible to very significantly raise the values of the breaking load at 20 ° C. and 100 ° C., thus as the creep resistance at 100 ° C, while still significantly reducing the creep rate.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Heat Treatment Of Steel (AREA)
  • Forging (AREA)
  • Continuous Casting (AREA)

Abstract

Zinc-based alloy containing from 5% to 40% of aluminium, from 0.5% to 5% of copper and up to 0.1% of magnesium, which additionally has a content of between 0.005% and 2.5% of at least one element chosen from the group comprising lithium (pref. 0.01% - 1%), manganese (pref.: 0.005% - 0.2%) and chromium (pref.: 0.005% - 0.5%).

Description

La présente invention concerne un alliage à base de zinc présentant une résistance à chaud et une résistance au fluage améliorées. Par résistance à chaud, il faut entendre la résistance à des températures de l'ordre de 100°C.The present invention relates to a zinc-based alloy having improved heat resistance and creep resistance. By hot resistance is meant resistance to temperatures of the order of 100 ° C.

Le domaine d'utilisation des alliages à base de zinc est actuellement étendu à de nombreuses applications intéressant de multiples aspects de l'industrie. C'est le cas, en particulier, des alliages de zinc destinés à la coulée.The field of use of zinc-based alloys is currently extended to numerous applications of interest to multiple aspects of the industry. This is the case, in particular, of zinc alloys intended for casting.

On a déjà cherché à améliorer les propriétés de tels alliages de zinc, en leur incorporant un ou plusieurs éléments, en quantités diverses, parfois même en très faible quantité, afin d'obtenir des alliages aptes à un éventail d'applications aussi large que possible.Attempts have already been made to improve the properties of such zinc alloys, by incorporating one or more elements into them, in various quantities, sometimes even in very small quantities, in order to obtain alloys suitable for as wide a range of applications as possible. .

On connaît notamment un alliage de zinc destiné à la coulée présentant une charge de rupture de l'ordre de 400 à 500 MPa. Cette valeur a été atteinte en assurant à l'alliage une teneur en aluminium comprise en­tre 5 % et 40 %, et de préférence voisine de 27 %, avec des additions de cuivre et de magnésium. Sa résistance au fluage et à la traction à chaud (100°C) sont cependant modestes. En effet, sa résistance à 100°C est, dans les meilleures conditions de coulée, de l'ordre de 300 MPa et sa durée de vie en fluage à 100°C sous une charge de 50 MPa est de 300 heures environ.A zinc alloy intended for casting is known in particular having a breaking load of the order of 400 to 500 MPa. This value was reached by ensuring the alloy an aluminum content of between 5% and 40%, and preferably close to 27%, with additions of copper and magnesium. Its resistance to creep and hot traction (100 ° C) are however modest. In fact, its resistance at 100 ° C. is, under the best casting conditions, of the order of 300 MPa and its creep life at 100 ° C. under a load of 50 MPa is approximately 300 hours.

La présente invention a pour objet un alliage à base de zinc, destiné à la coulée et présentant des propriétés améliorées de fluage et de résistance à chaud (100°C). En particulier, la durée de vie en fluage est améliorée ainsi que la vitesse de fluage et la résistance en trac­tion à 100°C.The present invention relates to a zinc-based alloy, intended for casting and having improved creep properties and resistance to heat (100 ° C). In particular, the creep life is improved as well as the creep rate and the tensile strength at 100 ° C.

Le composition de l'alliage conforme à l'invention résulte de la cons­tatation inattendue faite par le demandeur, selon laquelle il est possible d'améliorer :
- soit la résistance au fluage de l'alliage, au moyen d'additions de lithium et/ou de manganèse;
- soit la charge de rupture de l'alliage à 100°C, au moyen d'additions de chrome, de manganèse et/ou de lithium;
- soit ces deux propriétés simultanément en combinant judicieusement les additions précitées.
The composition of the alloy in accordance with the invention results from the unexpected observation made by the applicant, according to which it is possible to improve:
- Either the creep resistance of the alloy, by means of additions of lithium and / or manganese;
- Either the breaking load of the alloy at 100 ° C, by means of additions of chromium, manganese and / or lithium;
- or these two properties simultaneously by judiciously combining the above additions.

Conformément à l'invention, un alliage de zinc contenant 5 à 40 % d'aluminium, 0,5 % à 5 % de cuivre et jusqu'à 0,1 % de magnésium, est caractérisé en ce qu'il présente en outre une teneur comprise entre 0,005 % et 2,5 % en au moins un élément choisi dans le groupe compre­nant le lithium, le manganèse et le chrome.According to the invention, a zinc alloy containing 5 to 40% aluminum, 0.5% to 5% copper and up to 0.1% magnesium, is characterized in that it also has a content between 0.005% and 2.5% in at least one element chosen from the group comprising lithium, manganese and chromium.

Selon une première variante, ledit alliage de zinc contient du lithium en une teneur comprise entre 0,005 % et 2,5 %, et de préférence entre 0,01 % et 1.According to a first variant, said zinc alloy contains lithium in a content of between 0.005% and 2.5%, and preferably between 0.01% and 1.

Selon une deuxième variante, l'alliage de zinc présente une teneur en manganèse comprise entre 0,005 % et 0,2 %, et de préférence entre 0,1 % et 0,15 %.According to a second variant, the zinc alloy has a manganese content of between 0.005% and 0.2%, and preferably between 0.1% and 0.15%.

Selon une troisième variante, ledit alliage de zinc contient du chrome en une teneur comprise entre 0,005 % et 0,5 %.According to a third variant, said zinc alloy contains chromium in a content of between 0.005% and 0.5%.

Toujours selon l'invention, il est également intéressant que l'alliage contienne une addition combinée de lithium et de manganèse, de façon à additionner les améliorations de résistance à la traction et de résistance au fluage à 100°C de cet alliage de zinc.Still according to the invention, it is also advantageous for the alloy to contain a combined addition of lithium and manganese, so as to add the improvements in tensile strength and creep resistance at 100 ° C. of this zinc alloy.

Dans cette variante, l'alliage de zinc conforme à l'invention contient de 0,01 % à 1 % de lithium et de 0,005 % à 0,2 % de manganèse.In this variant, the zinc alloy according to the invention contains from 0.01% to 1% of lithium and from 0.005% to 0.2% of manganese.

Le demandeur a en effet constaté qu'un alliage Zn-Al-Li-Mn comportant des additions précitées de cuivre et de magnésium et répondant aux conditions ci-dessus présentait à la fois une charge de rupture à 100°C nettement accrue et une résistance au fluage plus élevée par rapport à un alliage ne contenant pas de manganèse. Le bénéfice est encore plus net si l'on se réfère à l'alliage de base, qui ne contient pas de lithium ni de manganèse.The applicant has in fact found that a Zn-Al-Li-Mn alloy comprising the above-mentioned additions of copper and magnesium and meeting the above conditions exhibited both a significantly increased breaking load at 100 ° C. and a resistance higher creep compared to an alloy containing no manganese. The benefit is even clearer if we refer to the base alloy, which does not contain lithium or manganese.

Selon une autre modalité particulière, un alliage de zinc conforme à l'invention contient du lithium en une teneur comprise entre 0,01 % et 1,5 % et du chrome en une teneur comprise entre 0,005 % et 0,5 %.According to another particular form, a zinc alloy in accordance with the invention contains lithium in a content of between 0.01% and 1.5% and chromium in a content of between 0.005% and 0.5%.

Toujours selon cette seconde modalité, il s'est également avéré intéressant de combiner les additions de chrome avec une addition de manganèse ne dépassant pas 0,2 %, de façon à combiner les améliora­tions de résistance à chaud d'un alliage de zinc conforme à l'invention que permettent ces deux éléments.Still according to this second method, it has also proved to be advantageous to combine the chromium additions with an addition of manganese not exceeding 0.2%, so as to combine the improvements in hot resistance of a zinc alloy conforming to the invention that these two elements allow.

A titre d'exemple, le tableau ci-dessous illustre l'effet des addi­tions, conformes à l'invention, qui viennent d'être décrites, sur la charge de rupture à froid et à chaud et sur la résistance au fluage d'un alliage à base de zinc contenant 27 % d'aluminium, 1 % de cuivre et 0,02 % de magnésium.

Figure imgb0001
By way of example, the table below illustrates the effect of the additions, in accordance with the invention, which have just been described, on the cold and hot breaking load and on the creep resistance of a zinc-based alloy containing 27% aluminum, 1% copper and 0.02% magnesium.
Figure imgb0001

L'alliage A est l'alliage de base connu antérieurement; il présente une résistance au fluage à 100°C et une résistance à la traction à 100°C peu élevées, exprimées par une durée de vie sous une charge de 50 MPa de 300 h et une résistance à chaud de 295 MPa.Alloy A is the basic alloy known previously; it has a low creep resistance at 100 ° C and a tensile strength at 100 ° C, expressed by a lifetime under a load of 50 MPa of 300 h and a heat resistance of 295 MPa.

L'alliage B conforme à la première variante de l'invention, montre qu'une addition de lithium dans les limites indiquées permet de re­lever très sensiblement les valeurs de la durée de vie en fluage et de la résistance en traction (à 20°C et 100°C), tout en diminuant la vitesse de fluage de l'alliage.Alloy B in accordance with the first variant of the invention shows that an addition of lithium within the limits indicated makes it possible to very significantly raise the values of the creep life and the tensile strength (at 20 ° C. and 100 ° C), while decreasing the creep rate of the alloy.

L'alliage C répondant à la deuxième variante, présente également une résistance au fluage accrue par rapport à l'alliage de base.Alloy C corresponding to the second variant, also has an increased creep resistance compared to the base alloy.

L'alliage D, qui correspond à la troisième variante, présente des charges de rupture à 20°C et 100°C nettement plus élevées que l'al­liage de base, associées à une durée de vie en fluage qui est également améliorée.Alloy D, which corresponds to the third variant, has significantly higher breaking loads at 20 ° C and 100 ° C than the base alloy, associated with a creep lifetime which is also improved.

L'alliage E, également conforme à l'invention, montre qu'une addition combinée de lithium et de manganèse dans les limites indiquées, permet de relever très sensiblement les valeurs de la charge de rupture à 20°C et 100°C, ainsi que la résistance au fluage à 100°C, tout en ré­duisant encore nettement la vitesse de fluage.Alloy E, also according to the invention, shows that a combined addition of lithium and manganese within the limits indicated, makes it possible to very significantly raise the values of the breaking load at 20 ° C. and 100 ° C., thus as the creep resistance at 100 ° C, while still significantly reducing the creep rate.

Claims (4)

1. Alliage à base de zinc contenant de 5 % à 40 % d'aluminium, de 0,5 % à 5 % de cuivre et jusqu'à 0,1 % de magnésium, caractérisé en ce qu'il présente en outre une teneur comprise entre 0,005 % et 2,5 % en au moins un élément choisi dans le groupe comprenant le lithium, le manganèse et le chrome.1. Zinc-based alloy containing 5% to 40% aluminum, 0.5% to 5% copper and up to 0.1% magnesium, characterized in that it also has a content between 0.005% and 2.5% in at least one element chosen from the group comprising lithium, manganese and chromium. 2. Alliage à base de zinc suivant la revendication 1, caractérisé en ce que sa teneur en lithium est comprise entre 0,01 % et 1 %.2. Zinc-based alloy according to claim 1, characterized in that its lithium content is between 0.01% and 1%. 3. Alliage à base de zinc suivant l'une des revendications 1 ou 2, caractérisé en ce que sa teneur en manganèse est comprise entre 0,005 % et 0,2 %, et de préférence encore entre 0,1 % et 0,15 %.3. Zinc-based alloy according to one of claims 1 or 2, characterized in that its manganese content is between 0.005% and 0.2%, and more preferably between 0.1% and 0.15% . 4. Alliage à base de zinc suivant l'une des revendications 1, 2 ou 3, caractérisé en ce que sa teneur en chrome est comprise entre 0,005 % et 0,5 %.4. Zinc-based alloy according to one of claims 1, 2 or 3, characterized in that its chromium content is between 0.005% and 0.5%.
EP19880870091 1987-05-13 1988-05-13 Heat resisting zinc base alloy Expired - Lifetime EP0291492B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
BE8700555 1987-05-13
BE8700555A BE1000566A7 (en) 1987-05-13 1987-05-13 Zinc alloy resistant hot.

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EP0291492A1 true EP0291492A1 (en) 1988-11-17
EP0291492B1 EP0291492B1 (en) 1993-01-20

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2016065498A1 (en) * 2014-10-29 2016-05-06 宁波博威合金材料股份有限公司 High-strength deformable zinc-based alloy material

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1767011A (en) * 1927-08-08 1930-06-24 Doehler Die Casting Co Alloy
GB362507A (en) * 1930-09-06 1931-12-07 Horace Campbell Hall An improved alloy particularly for bearing surfaces
GB411557A (en) * 1932-12-19 1934-06-14 Birmingham Aluminium Casting Improved zinc base alloy
GB522724A (en) * 1939-06-06 1940-06-25 Percy Oakley Improvements in zinc base alloys
BE775207A (en) * 1971-11-10 1972-05-10 Centre Rech Metallurgique Zinc-based alloys - with improved hot-creep resistance
FR2228850A1 (en) * 1973-05-08 1974-12-06 St Joe Minerals Corp

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1767011A (en) * 1927-08-08 1930-06-24 Doehler Die Casting Co Alloy
GB362507A (en) * 1930-09-06 1931-12-07 Horace Campbell Hall An improved alloy particularly for bearing surfaces
GB411557A (en) * 1932-12-19 1934-06-14 Birmingham Aluminium Casting Improved zinc base alloy
GB522724A (en) * 1939-06-06 1940-06-25 Percy Oakley Improvements in zinc base alloys
BE775207A (en) * 1971-11-10 1972-05-10 Centre Rech Metallurgique Zinc-based alloys - with improved hot-creep resistance
FR2228850A1 (en) * 1973-05-08 1974-12-06 St Joe Minerals Corp

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2016065498A1 (en) * 2014-10-29 2016-05-06 宁波博威合金材料股份有限公司 High-strength deformable zinc-based alloy material

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Publication number Publication date
BE1000566A7 (en) 1989-02-07
DE3877620D1 (en) 1993-03-04
EP0291492B1 (en) 1993-01-20

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