CN109136692B - Cast aluminum alloy and preparation method thereof - Google Patents
Cast aluminum alloy and preparation method thereof Download PDFInfo
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- CN109136692B CN109136692B CN201811217827.2A CN201811217827A CN109136692B CN 109136692 B CN109136692 B CN 109136692B CN 201811217827 A CN201811217827 A CN 201811217827A CN 109136692 B CN109136692 B CN 109136692B
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C21/00—Alloys based on aluminium
- C22C21/12—Alloys based on aluminium with copper as the next major constituent
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C1/00—Making non-ferrous alloys
- C22C1/02—Making non-ferrous alloys by melting
- C22C1/026—Alloys based on aluminium
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C1/00—Making non-ferrous alloys
- C22C1/02—Making non-ferrous alloys by melting
- C22C1/03—Making non-ferrous alloys by melting using master alloys
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C1/00—Making non-ferrous alloys
- C22C1/06—Making non-ferrous alloys with the use of special agents for refining or deoxidising
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
- C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
- C22F1/002—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working by rapid cooling or quenching; cooling agents used therefor
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
- C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
- C22F1/04—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working of aluminium or alloys based thereon
- C22F1/057—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working of aluminium or alloys based thereon of alloys with copper as the next major constituent
Abstract
The invention relates to a heat-resistant cast aluminum alloy and a preparation method thereof, wherein the cast aluminum alloy comprises the following components in percentage by weight: 5.0-5.5% of Cu; 1.0-1.3% of Ni; 0.3-0.4% of Mn; 0.2-0.25% of Ti; v is 0.01-0.25%; impurities < 0.3%; the balance of Al. The tensile strength of the novel cast aluminum alloy developed by the invention can reach 120MPa at 320 ℃ and is higher than that of ZL201A and ZL208 alloys, and the room temperature strength can reach more than 340MPa and is higher than that of ZL208 alloys. Therefore, the comprehensive mechanical property of the heat-resistant cast aluminum alloy is higher than that of ZL201A alloy and ZL208 alloy.
Description
Technical Field
The invention relates to the field of cast aluminum alloy, in particular to a heat-resistant cast aluminum alloy and a preparation method thereof.
Background
As an aluminum alloy part playing a key role on an aircraft engine power system, the aluminum alloy part has a complex structure, needs to operate under high temperature, high pressure, high speed and friction environment for a long time, and is required to have excellent casting performance and excellent room temperature and high temperature performance. The room temperature strength of the cast aluminum alloy is improved mainly by strengthening phases such as Al2Si and Al2Cu formed in a G-P region. The current domestic alloys with better room temperature performance comprise ZL114A, ZL205A, ZL201A and the like, wherein the room temperature strength of ZL205A can reach more than 500MPa, and the alloys have very good room temperature mechanical properties, but the characteristics of complex components, higher price, poor casting performance and the like limit the application of the alloys in general industry. The improvement of the high-temperature performance of the alloy needs to improve the high-temperature strength of the strengthening phase and the pinning effect of the high-temperature resistant dispersion particles on dislocation in the high-temperature deformation process, the formation of the high-temperature strengthening phase is related to the components and complexity of the strengthening phase besides the heat treatment system, and the high-temperature performance of the dispersion particles is related to the electron bonding strength of the outermost atom layer of the intermetallic compound and the coherent relationship between the dispersion particles and the matrix. At present, researches on heat-resistant aluminum alloys mainly focus on the influence of elements such as Ag, Re, Sc and the like on a strengthening phase and dispersed particles, but Sc and Ag are expensive metals and have low economical efficiency, and new elements capable of replacing the elements are required to be searched. Therefore, research on novel casting heat-resistant aluminum alloy is more and more focused by scientific research and production departments.
The cast heat-resistant aluminum alloy is mainly divided into two types of Al-Si series and Al-Cu series, the Al-Si series alloy has good casting performance and low strength, for example ZL105A (AlSi5Cu1Mg) can keep good mechanical property at about 150 ℃, but when the temperature exceeds 250 ℃, the mechanical property is greatly reduced. Most Al-Cu series cast aluminum alloys have good high-temperature performance, such as ZL208(AlCu5Ni2CoZr) with tensile strength of 120MPa at 316 ℃ but low room-temperature strength of 220-250 MPa, ZL201A alloy with high room-temperature strength of over 390MPa but poor high-temperature durability with sigma at 300 DEG C100Is 78 MPa.
Disclosure of Invention
An object of the present invention is to solve at least one of the above problems, and the present invention provides a heat-resistant type cast aluminum alloy and a method for producing the same. The cast aluminum alloy can be used for manufacturing high-quality aluminum alloy castings of aero-engine accessory casings, shells and the like with the long-term working temperature of 350 ℃.
According to one aspect of the invention, there is provided a cast aluminum alloy consisting of, in weight percent:
5.0-5.5% of Cu; 1.0-1.3% of Ni; 0.3-0.4% of Mn; 0.2-0.25% of Ti; v is 0.1-0.25%; impurities < 0.3%; the balance of Al.
Wherein, in the cast aluminum alloy, V is 0.1-0.25%.
Wherein, in the cast aluminum alloy, Cu is 5.0-5.5%.
Wherein, the impurities comprise the following components in percentage by weight: si < 0.1%; fe < 0.1%; zn is less than 0.1 percent.
According to another aspect of the present invention, there is provided a method for producing the cast aluminum alloy, comprising the steps of:
a. commercial refined aluminum (99.99%), AlCu50A master alloy, AlNi10 master alloy, and AlMn10 master alloy were preheated at a first temperature for a period of time.
b. And heating and melting the preheated mixed alloy.
c. And after the molten alloy is completely melted, adjusting the temperature of the molten alloy to an intermediate temperature, stirring for 10-15 min by using a graphite rod, then heating to a second temperature, adding the calculated AlTi10A intermediate alloy and AlV5A intermediate alloy in batches, and stirring for 10-15 min by using the graphite rod after the intermediate alloy is completely melted to form the cast aluminum alloy molten liquid.
d. And regulating the temperature of the cast aluminum alloy melt to a third temperature for refining.
e. And standing for 15-20 min after refining, skimming, and adjusting the temperature of the cast aluminum alloy melt to a fourth temperature to pour the test bar.
f. And (3) sequentially carrying out solid solution treatment, quenching treatment and aging treatment on the test bar to obtain the cast aluminum alloy tensile test bar.
Wherein, in the step c: the intermediate temperature is 720 ℃ and the second temperature is 750 +/-5 ℃.
Wherein, in the step d: the third temperature is 730 +/-5 ℃.
Wherein, in step e: the fourth temperature is 720-725 ℃.
Wherein, in the step d: the refining agent accounts for 0.3-0.5 percent of the total weight of all the raw materials, and the refining agent is an aluminum alloy refining agent containing inorganic salt or hexachloroethane.
Wherein, in the step f: the temperature of the solution treatment is 530 +/-5 ℃, and the heat preservation time of the solution treatment is 12-18 hours; the cooling medium for quenching treatment is water, the water temperature is 80-100 ℃, and the quenching transfer time is less than 20 s; the temperature of the aging treatment is 175 +/-5 ℃, and the heat preservation time of the aging treatment is 4-6 hours. And air cooling to room temperature after the heat preservation time.
The room temperature strength strengthening phase of the heat-resistant cast aluminum alloy is Al2Cu, the high temperature strength strengthening phase is an L12 phase compound Al7V which is formed by V element in the alloy solidification process, is coherent with a matrix, has extremely low solubility in the matrix, and Al7V plays a role in pinning dislocation motion caused by deformation during high temperature stretching, so that the high temperature strength of the alloy is improved.
The invention has the following beneficial effects:
in order to comprehensively improve the room temperature and high temperature performance of the cast aluminum alloy, on the basis of ZL201A, the room temperature and high temperature strengthening phase of the cast aluminum alloy is changed by adjusting the content of Cu element and adding a proper amount of V element, so that the aim of improving the high temperature strength of the alloy while ensuring the room temperature strength of the cast aluminum alloy is fulfilled. The tensile strength of the novel cast aluminum alloy developed by the invention can reach 120MPa at 320 ℃ and is higher than that of ZL201A and ZL208 alloys, and the room temperature strength can reach more than 340MPa and is higher than that of ZL208 alloys. Therefore, the comprehensive mechanical property of the heat-resistant cast aluminum alloy is higher than that of ZL201A alloy and ZL208 alloy.
Drawings
Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the invention. Also, like reference numerals are used to refer to like parts throughout the drawings. In the drawings:
fig. 1, 2 and 3 show pictures of microstructures at 200 times and 500 times of the novel cast alloy according to an embodiment of the present invention.
Detailed Description
Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.
Example 1 cast aluminum alloy X1
Comprises the following components in percentage by weight: cu: 5.0 percent; ni: 1.3 percent; mn: 0.4 percent; ti: 0.25 percent; v: 0.25 percent; other impurities Si is less than 0.1%; fe < 0.1%; zn is less than 0.1 percent; the balance of Al.
As shown in figure 1, the X1 alloy has a fine and uniform structure, crystal grains mainly exist in a cellular or dendritic form, a theta (Al2Cu) phase, an Al3Ni phase and an Al6Cu3Ni phase are distributed among dendritic crystals or on grain boundaries, a T (Al12CuMn2) phase and an Al7V phase are distributed in a dispersed mode in the crystal, and the theta (Al2Cu) phase is low in content and low in mechanical property at room temperature, and is generally 320-340 MPa.
Example 2 cast aluminum alloy X2
Comprises the following components in percentage by weight: cu: 5.2 percent; ni: 1.0 percent; mn: 0.3 percent; ti: 0.2 percent; v: 0.1 percent; other impurities Si is less than 0.1%; fe < 0.1%; zn is less than 0.1 percent; the balance of Al.
As shown in figure 2, the content of Ti and V in the X2 alloy is low, the refining effect of Ti and V on crystal grains is weakened, the size of the crystal grains in the alloy structure is 2-3 times of that of X1 alloy crystal grains, the crystal grains exist in a blocky or cellular form, a skeletal Al6Cu3Ni phase with large intercrystalline size cracks a matrix structure, dispersed particles distributed in the crystal are less than X1, the mechanical property at room temperature is low and not higher than 320MPa, the mechanical property at high temperature is low, and the tensile strength at 320 ℃ is not higher than 120 MPa.
Example 3 cast aluminum alloy X3
Comprises the following components in percentage by weight: cu: 5.3 percent; ni: 1.2 percent; mn: 0.35 percent; ti: 0.22 percent; v: 0.2 percent; other impurities Si is less than 0.1%; fe < 0.1%; zn is less than 0.1 percent; the balance of Al.
As shown in FIG. 3, the structure form of the X3 alloy is mainly cellular or dendritic, the grain size is consistent with that of X1, but the quantity of intercrystalline theta (Al2Cu) phase and intragranular dispersed particles is more than that of X1, and the X1 alloy has higher room temperature and high temperature mechanical properties.
The obtained aluminum alloy X3 test bars were subjected to tensile tests at room temperature and 320 ℃ to obtain strengths and elongations at different temperatures, and the results are shown in tables 1 and 2.
TABLE 1 mechanical properties of the alloy at room temperature
TABLE 2 mechanical properties of the alloy at 320 DEG C
As can be seen from tables 1 and 2, the tensile strength of the novel cast aluminum alloy X3 developed by the invention can reach 120MPa at 320 ℃, which is higher than that of ZL201A and ZL208 alloys, and the room temperature strength can reach more than 340MPa, which is higher than that of ZL208 alloys.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.
Claims (7)
1. The cast aluminum alloy is characterized by comprising the following components in percentage by weight:
cu: 5.3 percent; ni: 1.2 percent; mn: 0.35 percent; ti: 0.22 percent; v: 0.2 percent; other impurities Si is less than 0.1%; fe < 0.1%; zn is less than 0.1 percent; the balance of Al.
2. The method of making a cast aluminum alloy of claim 1, comprising the steps of:
a. preheating industrial refined aluminum, AlCu50A intermediate alloy, AlNi10 intermediate alloy and AlMn10 intermediate alloy at a first temperature for a period of time;
b. heating and melting the preheated mixed alloy;
c. after the molten aluminum alloy is completely melted, adjusting the temperature of the molten aluminum alloy to an intermediate temperature, uniformly mixing, heating to a second temperature, adding an AlTi10A intermediate alloy and an AlV5A intermediate alloy, and stirring to form a molten aluminum alloy for casting;
d. adjusting the temperature of the cast aluminum alloy melt to a third temperature for refining;
e. standing for a period of time, and regulating the temperature of the cast aluminum alloy melt to a fourth temperature to pour the test bar;
f. and (3) sequentially carrying out solid solution treatment, quenching treatment and aging treatment on the test bar to obtain the cast aluminum alloy tensile test bar.
3. The method of producing a cast aluminum alloy of claim 2, wherein in step c:
the intermediate temperature is 720 ℃ and the second temperature is 750 +/-5 ℃.
4. The method of producing a cast aluminum alloy of claim 2, wherein in step d:
the third temperature is 730 +/-5 ℃.
5. The method of producing a cast aluminum alloy according to claim 2, wherein in step e:
the fourth temperature is 720-725 ℃.
6. The method of producing a cast aluminum alloy of claim 2, wherein in step d:
the refining agent accounts for 0.3-0.5 percent of the total weight of all the raw materials, and the refining agent is an aluminum alloy refining agent containing inorganic salt or hexachloroethane.
7. The method of producing a cast aluminum alloy according to claim 2, wherein in step f:
the temperature of the solution treatment is 530 +/-5 ℃, and the heat preservation time of the solution treatment is 12-18 hours;
the cooling medium for quenching treatment is water, and the water temperature is 80-100 ℃;
the temperature of the aging treatment is 175 +/-5 ℃, and the heat preservation time of the aging treatment is 4-6 hours.
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| CN110904352A (en) * | 2019-12-05 | 2020-03-24 | 南通爱尔思轻合金精密成型有限公司 | Smelting homogenization process for ZL201 cast aluminum alloy |
| CN113755727B (en) * | 2021-08-23 | 2022-05-03 | 广西大学 | Heat-resistant aluminum-based composite material and preparation method thereof |
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| CN100347322C (en) * | 2005-09-12 | 2007-11-07 | 华南理工大学 | Extrusion cast aluminium alloy material with high strength and toughness |
| CN100410406C (en) * | 2006-08-14 | 2008-08-13 | 吉林大学 | High strength high toughness casting aluminum alloy |
| CN101265540A (en) * | 2008-04-02 | 2008-09-17 | 苏州明志科技有限公司 | Thermal fatigue resisting aluminum alloy |
| JP2010159488A (en) * | 2008-12-09 | 2010-07-22 | Sumitomo Light Metal Ind Ltd | Method for molding 2,000 series aluminum alloy material, and formed product molded by the same |
| CN102758109B (en) * | 2012-08-07 | 2014-09-24 | 曾琦 | High-strength wear-resisting heat-resisting aluminium alloy material and preparation process thereof |
| CN103924139B (en) * | 2014-04-25 | 2015-11-25 | 天津那诺机械制造有限公司 | A kind of high-strength aluminum copper alloy wheel material and liquid forging forming method |
| EP3048179B1 (en) * | 2015-01-21 | 2017-05-24 | Nemak, S.A.B. de C.V. | Method for forming complex cast parts and cast part consisting of an AlCu alloy |
| CN104561690B (en) * | 2015-01-26 | 2017-01-18 | 上海交通大学 | High-plasticity cast aluminum alloy and extrusion casting preparation method thereof |
| JP2017128789A (en) * | 2016-01-19 | 2017-07-27 | 株式会社神戸製鋼所 | Heat resistant aluminum alloy shape material and aluminum alloy member |
| CN105970039B (en) * | 2016-06-29 | 2018-05-25 | 贵州华科铝材料工程技术研究有限公司 | A kind of aluminum alloy materials and its centre spinning method for substituting QT500 loom wheel hubs |
| CN105970010B (en) * | 2016-06-29 | 2018-09-21 | 贵州华科铝材料工程技术研究有限公司 | A kind of aluminum alloy materials and its gravity casting method substituting QT400 light-duty vehicle steering gears |
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