阅读说明：本技术 一种用于建筑承载结构的铝合金及其制备方法 (Aluminum alloy for building bearing structure and preparation method thereof ) 是由 郭加林 周明君 曾阳阳 管晓伟 于 2021-08-11 设计创作，主要内容包括：本发明公开了一种用于建筑承载结构的铝合金,其主要由以下质量百分比的成分组成：Si 0.6～0.9％,Mg 0.9～1.3％,Cu 0.3～0.5％,Mn 0.1～0.3％,Fe 0.4～0.8％,Cr 0.2～0.4％,Ti 0.1～0.2％,余量为Al和不可避免的杂质,所述不可避免杂质的含量≤0.15％。相应的,本发明还公开了上述用于建筑承载结构的铝合金的制备方法。本发明中的铝合金耐腐蚀性能、粘接性能优良,可广泛应用于建筑承载结构,实现建筑主体轻量化。(The invention discloses an aluminum alloy for a building bearing structure, which mainly comprises the following components in percentage by mass: 0.6-0.9% of Si, 0.9-1.3% of Mg, 0.3-0.5% of Cu, 0.1-0.3% of Mn, 0.4-0.8% of Fe, 0.2-0.4% of Cr, 0.1-0.2% of Ti, and the balance of Al and inevitable impurities, wherein the content of the inevitable impurities is less than or equal to 0.15%. Correspondingly, the invention also discloses a preparation method of the aluminum alloy for the building bearing structure. The aluminum alloy has excellent corrosion resistance and bonding performance, can be widely applied to building bearing structures, and realizes the light weight of building main bodies.)

1. An aluminum alloy for a building load-bearing structure is characterized by mainly comprising the following components in percentage by mass: 0.6-0.9% of Si, 0.9-1.3% of Mg, 0.3-0.5% of Cu, 0.1-0.3% of Mn, 0.4-0.8% of Fe, 0.2-0.4% of Cr, 0.1-0.2% of Ti, and the balance of Al and inevitable impurities, wherein the content of the inevitable impurities is less than or equal to 0.15%.

2. The aluminum alloy for a load bearing structure of buildings as claimed in claim 1, which consists essentially of the following components in mass percent: 0.8-0.9% of Si, 0.9-1.1% of Mg, 0.3-0.4% of Cu, 0.2-0.3% of Mn, 0.7-0.8% of Fe, 0.2-0.3% of Cr, 0.1-0.2% of Ti, and the balance of Al and inevitable impurities, wherein the content of the inevitable impurities is less than or equal to 0.15%.

3. The aluminum alloy for building load-bearing structure as recited in claim 1 or 2, wherein the aluminum alloy has a corrosion rate of 10.5mm/a or less in saturated lime water and a bonding strength with concrete of 2.3MPa or more.

4. A method of making an aluminium alloy for a load bearing structure of a building as claimed in any one of claims 1 to 3, comprising:

(1) preparing various raw materials according to a proportion for later use; the formula of the raw materials in percentage by weight is as follows:

0.6-0.9% of Si, 0.9-1.3% of Mg, 0.3-0.5% of Cu, 0.1-0.3% of Mn, 0.4-0.8% of Fe, 0.2-0.4% of Cr, 0.1-0.2% of Ti, and the balance of Al and inevitable impurities, wherein the content of the inevitable impurities is less than or equal to 0.15%;

(2) mixing and casting various raw materials to obtain a cast rod;

(3) homogenizing the cast rod;

(4) extruding the homogenized cast rod to obtain a rough blank;

(5) straightening the aluminum rough blank;

(6) and carrying out aging treatment on the straightened rough blank to obtain the finished product of the aluminum alloy for the building bearing structure.

5. The method for preparing the aluminum alloy for the building load-bearing structure as recited in claim 4, wherein in the step (3), the homogenizing temperature is 570-600 ℃, and the homogenizing time is 8-10 h;

and after homogenizing treatment, cooling by adopting water mist.

6. The method for preparing the aluminum alloy for building load-bearing structure according to claim 4, wherein in the step (4), the extrusion temperature is 510-530 ℃ and the extrusion speed is 3-8 m/min.

7. The method for preparing the aluminum alloy for building load-bearing structure according to claim 6, wherein after the extrusion is finished, the aluminum alloy is cooled by water and quenched on line.

8. The method of claim 4, wherein in step (5), the straightening ratio is 0.2-0.6%.

9. The method for preparing the aluminum alloy for building load-bearing structure according to claim 4, wherein in the step (6), the aging treatment temperature is 160-180 ℃ and the time is 16-24 h.

Technical Field

The invention relates to the technical field of aluminum alloy, in particular to aluminum alloy for a building bearing structure and a preparation method thereof.

Background

At present, the building industry tends to be greener, and in the process of selecting building materials, materials with light weight, high strength and corrosion resistance are selected as much as possible in principle, so that the service life of a building is prolonged, and the light weight of the building is realized. Under the background, aluminum is used for replacing steel, and aluminum is used for replacing plastic, which is a great trend in the building industry. For example, aluminum alloys are widely used in the construction of airports, exhibition halls, traffic stations, and bridges. Even in some occasions, the foundation of the ground bottom can be deepened, and then a large amount of aluminum alloy is adopted, so that the light weight of the building is realized.

However, when the existing aluminum alloy is used with concrete, the problems of poor corrosion resistance and low bonding strength often exist, and the application of the existing aluminum alloy is limited.

Disclosure of Invention

The invention aims to provide an aluminum alloy for a building bearing structure, which has strong corrosion resistance and high bonding strength.

The invention also aims to provide a preparation method of the aluminum alloy for the building bearing structure.

In order to solve the technical problem, the invention provides an aluminum alloy for a building bearing structure, which mainly comprises the following components in percentage by mass: 0.6-0.9% of Si, 0.9-1.3% of Mg, 0.3-0.5% of Cu, 0.1-0.3% of Mn, 0.4-0.8% of Fe, 0.2-0.4% of Cr, 0.1-0.2% of Ti, and the balance of Al and inevitable impurities, wherein the content of the inevitable impurities is less than or equal to 0.15%.

As an improvement of the technical scheme, the material mainly comprises the following components in percentage by mass: 0.8-0.9% of Si, 0.9-1.1% of Mg, 0.3-0.4% of Cu, 0.2-0.3% of Mn, 0.7-0.8% of Fe, 0.2-0.3% of Cr, 0.1-0.2% of Ti, and the balance of Al and inevitable impurities, wherein the content of the inevitable impurities is less than or equal to 0.15%.

As an improvement of the technical scheme, the corrosion rate of the aluminum alloy in saturated lime water is less than or equal to 10.5mm/a, and the bonding strength of the aluminum alloy and concrete is more than or equal to 2.3 MPa.

Correspondingly, the invention also discloses a preparation method of the aluminum alloy for the building bearing structure, which comprises the following steps:

(1) preparing various raw materials according to a proportion for later use; the formula of the raw materials in percentage by weight is as follows:

0.6-0.9% of Si, 0.9-1.3% of Mg, 0.3-0.5% of Cu, 0.1-0.3% of Mn, 0.4-0.8% of Fe, 0.2-0.4% of Cr, 0.1-0.2% of Ti, and the balance of Al and inevitable impurities, wherein the content of the inevitable impurities is less than or equal to 0.15%;

(2) mixing and casting various raw materials to obtain a cast rod;

(3) homogenizing the cast rod;

(4) extruding the homogenized cast rod to obtain a rough blank;

(5) straightening the aluminum rough blank;

(6) and carrying out aging treatment on the straightened rough blank to obtain the finished product of the aluminum alloy for the building bearing structure.

As an improvement of the technical scheme, in the step (3), the homogenizing temperature is 570-600 ℃, and the homogenizing time is 8-10 h;

and after homogenizing treatment, cooling by adopting water mist.

As an improvement of the technical scheme, in the step (4), the extrusion temperature is 510-530 ℃, and the extrusion speed is 3-8 m/min.

As an improvement of the technical scheme, after extrusion is finished, water cooling is carried out, and online quenching is carried out.

As an improvement of the technical scheme, in the step (5), the straightening rate is 0.2-0.6%.

As an improvement of the technical scheme, in the step (6), the aging treatment temperature is 160-180 ℃, and the time is 16-24 hours.

The implementation of the invention has the following beneficial effects:

the aluminum alloy for the building bearing structure is endowed with excellent corrosion resistance and bonding performance through reasonable formula adjustment and improvement of the preparation method. Specifically, the corrosion rate of the catalyst in saturated lime water is less than or equal to 10.5mm/a, the corrosion rate in simulated acid rain is less than or equal to 0.03mm/a, and the corrosion rate in a 5% NaCl solution is less than or equal to 0.01 mm/a. The bonding strength between the adhesive and concrete is more than or equal to 2.3 MPa.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be further described in detail with reference to specific embodiments.

The invention provides an aluminum alloy for a building bearing structure, which mainly comprises the following components in percentage by mass: 0.6-0.9% of Si, 0.9-1.3% of Mg, 0.3-0.5% of Cu, 0.1-0.3% of Mn, 0.4-0.8% of Fe, 0.2-0.4% of Cr, 0.1-0.2% of Ti, and the balance of Al and inevitable impurities, wherein the content of the inevitable impurities is less than or equal to 0.15%.

Wherein Si and Mg are the main strengthening elements which can combine to form Mg₂Si crystal phase, and optimizes various mechanical properties of the aluminum alloy. The content of Si is 0.6 to 0.9 wt%, and exemplary is 0.6 wt%, 0.7 wt%, 0.8 wt%, or 0.9 wt%, but not limited thereto. The content of Mg is 0.9 to 1.3 wt%, and exemplary is 0.9 wt%, 1.0 wt%, 1.1 wt%, or 1.2 wt%, but not limited thereto. In the invention, the Mg/Si ratio is controlled to be 1.2-1.5 so as to improve the extrusion performance.

Wherein, Fe can improve the corrosion resistance in alkaline solution (such as saturated lime water and cement paste) to a certain extent, but the Fe can also greatly influence the extrusion performance. For this purpose, the content is controlled to be 0.4 to 0.8 wt%, illustratively 0.4 wt%, 0.5 wt%, 0.6 wt%, 0.7 wt%, or 0.8 wt%.

Among them, Cu can improve the mechanical properties of aluminum profiles, but it can improve the quenching sensitivity. Therefore, the content is controlled to be 0.3 to 0.5 wt%; exemplary may be 0.3 wt%, 0.4 wt%, 0.45 wt%, or 0.5 wt%, but is not limited thereto.

Both Mn and Ti have a certain effect of refining crystal grains, and are beneficial to improving the mechanical property and the extrusion property of the aluminum alloy. Meanwhile, Mn can also adjust the quenching sensitivity of the aluminum alloy. In the present invention, the content of Mn is controlled to be 0.1 to 0.3 wt%, illustratively 0.1 wt%, 0.2 wt%, or 0.3 wt%, but is not limited thereto. The content of Ti is controlled to be 0.1 to 0.2%, and exemplary is 0.1 wt%, 0.15 wt%, or 0.18 wt%, but not limited thereto.

Cr can adjust the quenching sensitivity of the aluminum alloy and improve the corrosion resistance; the amount thereof is 0.2 to 0.4 wt%, illustratively 0.2 wt%, 0.3 wt%, or 0.4 wt%, but is not limited thereto.

In addition, in the aluminum alloy, some inevitable impurities are contained in a total amount of 0.15 wt.% or less.

Preferably, the aluminum alloy comprises the following components in percentage by mass:

0.8-0.9% of Si, 1.0-1.3% of Mg, 0.3-0.4% of Cu, 0.2-0.3% of Mn, 0.7-0.8% of Fe, 0.2-0.3% of Cr, 0.1-0.2% of Ti, and the balance of Al and inevitable impurities, wherein the content of the inevitable impurities is less than or equal to 0.15%.

Correspondingly, the invention also discloses a preparation method of the aluminum alloy for the building bearing structure, which comprises the following steps:

(1) preparing various raw materials according to a proportion for later use;

the formula of the raw materials in percentage by weight is as follows:

0.6-0.9% of Si, 0.9-1.1% of Mg, 0.3-0.5% of Cu, 0.1-0.3% of Mn, 0.4-0.8% of Fe, 0.2-0.4% of Cr, 0.1-0.2% of Ti, and the balance of Al and inevitable impurities, wherein the content of the inevitable impurities is less than or equal to 0.15%.

Wherein, the raw materials can comprise: aluminum ingot, aluminum-magnesium alloy, high purity silicon, aluminum-copper alloy, aluminum-chromium alloy, and the like, but are not limited thereto.

(2) Mixing and casting various raw materials to obtain a cast rod;

specifically, various raw materials are melted at 730-760 ℃, refined for 3-4 times, subjected to slag skimming, stirred for homogenization, and cast after standing to obtain the cast rod.

(3) Homogenizing the cast rod;

specifically, the homogenizing temperature is 570-600 ℃, and the homogenizing time is 8-10 h. And (5) cooling by adopting water mist after homogenizing.

The solid solubility of each alloy element in the aluminum alloy can be improved through the homogenization treatment, so that the mechanical property is improved. In the invention, by increasing the homogenizing temperature and prolonging the time, the size of the strengthening phase obtained by solid solution of the alloy elements is increased, the strengthening phase is exposed after the aluminum alloy is slightly corroded by concrete, and the friction force between the strengthening phase and the concrete is increased, so that the bonding strength between the aluminum alloy and the concrete is improved.

Exemplary, homogenization temperatures are 580 deg.C, 585 deg.C, 590 deg.C, or 595 deg.C, but are not limited thereto.

(4) Extruding the homogenized cast rod to obtain a rough blank;

specifically, the extrusion speed is 3 to 8m/min, and is exemplified by 3m/min, 4m/min, 5m/min, 6m/min or 7m/min, but is not limited thereto.

After extrusion, the mixture is directly cooled by water and quenched on line.

(5) Straightening the rough blank;

specifically, the straightening ratio is 0.2 to 0.6%, and is illustratively 0.2%, 0.3%, 0.4%, 0.5%, or 0.6%, but is not limited thereto.

(6) Carrying out aging treatment on the straightened rough blank to obtain an aluminum alloy for the building bearing structure;

specifically, the aging temperature is 160 to 180 ℃, and exemplary aging temperatures are 160 ℃, 165 ℃, 170 ℃, 175 ℃ or 180 ℃, but not limited thereto. The aging time is 16-24 h, and 17h, 18h, 19h, 20h, 22h or 23h is exemplified, but not limited thereto.

In conclusion, through the comprehensive adjustment of the formula and the preparation method, the corrosion rate of the aluminum alloy in the saturated lime water is less than or equal to 10.5mm/a, and the bonding strength between the aluminum alloy and the concrete is more than or equal to 2.3 MPa.

The invention is further illustrated by the following specific examples:

example 1

The embodiment provides an aluminum alloy for a building bearing structure, which comprises the following components in percentage by weight:

0.6% of Si, 1.3% of Mg, 0.4% of Fe, 0.5% of Cu, 0.3% of Mn, 0.4% of Cr, 0.2% of Ti, 0.15% of impurities and the balance of Al.

The preparation method comprises the following steps:

(1) preparing various raw materials according to a proportion for later use;

(2) mixing and casting various raw materials to obtain a cast rod;

(3) homogenizing the cast rod;

wherein the homogenizing temperature is 570 ℃, and the time is 10 h;

(4) extruding the homogenized cast rod to obtain a rough blank;

wherein the extrusion temperature is 530 ℃, and the extrusion speed is 8 m/min.

(5) Straightening the rough blank;

wherein, the straightening amount is 0.3 percent;

(6) and carrying out aging treatment on the straightened rough blank to obtain the finished product of the aluminum alloy for the building bearing structure.

Wherein the aging temperature is 180 ℃ and the time is 16 h.

Example 2

The embodiment provides an aluminum alloy for a building bearing structure, which comprises the following components in percentage by weight:

0.9% of Si, 0.9% of Mg, 0.8% of Fe, 0.3% of Cu, 0.1% of Mn, 0.2% of Cr, 0.1% of Ti, 0.08% of impurities and the balance of Al.

The preparation method comprises the following steps:

(1) preparing various raw materials according to a proportion for later use;

(2) mixing and casting various raw materials to obtain a cast rod;

(3) homogenizing the cast rod;

wherein the homogenizing temperature is 580 ℃, and the time is 8.5 h;

(4) extruding the homogenized cast rod to obtain a rough blank;

wherein the extrusion temperature is 510 ℃ and the extrusion speed is 3 m/min.

(5) Straightening the rough blank;

wherein, the straightening amount is 0.4 percent;

(6) and carrying out aging treatment on the straightened rough blank to obtain the finished product of the aluminum alloy for the building bearing structure.

Wherein the aging temperature is 160 ℃ and the time is 24 h.

Example 3

The embodiment provides an aluminum alloy for a building bearing structure, which comprises the following components in percentage by weight:

0.85% of Si, 1.1% of Mg, 0.7% of Fe, 0.32% of Cu, 0.25% of Mn, 0.33% of Cr, 0.16% of Ti, 0.12% of impurities and the balance of Al.

The preparation method comprises the following steps:

(1) preparing various raw materials according to a proportion for later use;

(2) mixing and casting various raw materials to obtain a cast rod;

(3) homogenizing the cast rod;

wherein the homogenizing temperature is 590 ℃, and the time is 9 h;

(4) extruding the homogenized cast rod to obtain a rough blank;

wherein the extrusion temperature is 515 ℃ and the extrusion speed is 5 m/min.

(5) Straightening the rough blank;

wherein, the straightening amount is 0.6 percent;

(6) and carrying out aging treatment on the straightened rough blank to obtain the finished product of the aluminum alloy for the building bearing structure.

Wherein the aging temperature is 170 ℃ and the time is 20 h.

Example 4

The embodiment provides an aluminum alloy for a building bearing structure, which comprises the following components in percentage by weight:

0.85% of Si, 1.1% of Mg, 0.5% of Fe, 0.32% of Cu, 0.25% of Mn, 0.33% of Cr, 0.16% of Ti, 0.12% of impurities and the balance of Al.

The preparation method comprises the following steps:

(1) preparing various raw materials according to a proportion for later use;

(2) mixing and casting various raw materials to obtain a cast rod;

(3) homogenizing the cast rod;

wherein the homogenizing temperature is 590 ℃, and the time is 9 h;

(4) extruding the homogenized cast rod to obtain a rough blank;

wherein the extrusion temperature is 515 ℃ and the extrusion speed is 5 m/min.

(5) Straightening the rough blank;

wherein, the straightening amount is 0.6 percent;

(6) and carrying out aging treatment on the straightened rough blank to obtain the finished product of the aluminum alloy for the building bearing structure.

Wherein the aging temperature is 170 ℃ and the time is 20 h.

Example 5

The embodiment provides an aluminum alloy for a building bearing structure, which comprises the following components in percentage by weight:

0.82% of Si, 1.04% of Mg, 0.75% of Fe, 0.46% of Cu, 0.28% of Mn, 0.33% of Cr, 0.18% of Ti, 0.05% of impurities and the balance of Al.

The preparation method comprises the following steps:

(1) preparing various raw materials according to a proportion for later use;

(2) mixing and casting various raw materials to obtain a cast rod;

(3) homogenizing the cast rod;

wherein the homogenizing temperature is 590 ℃, and the time is 9 h;

(4) extruding the homogenized cast rod to obtain a rough blank;

wherein the extrusion temperature is 515 ℃ and the extrusion speed is 5 m/min.

(5) Straightening the rough blank;

wherein, the straightening amount is 0.6 percent;

(6) and carrying out aging treatment on the straightened rough blank to obtain the finished product of the aluminum alloy for the building bearing structure.

Wherein the aging temperature is 170 ℃ and the time is 20 h.

Comparative example 1

The present comparative example provides an aluminum alloy for a building load bearing structure, the formulation of which is:

0.85% of Si, 1.1% of Mg, 0.2% of Fe, 0.32% of Cu, 0.25% of Mn, 0.33% of Cr, 0.16% of Ti, 0.12% of impurities and the balance of Al.

The preparation method is the same as in example 4.

Comparative example 2

The present comparative example provides an aluminum alloy for a building load bearing structure, the formulation of which is:

0.85% of Si, 1.1% of Mg, 0.7% of Fe, 0.32% of Cu, 0.25% of Mn, 0.05% of Cr, 0.16% of Ti, 0.12% of impurities and the balance of Al.

The preparation method is the same as in example 4.

Comparative example 3

The present comparative example provides an aluminum alloy for a building load bearing structure, the formulation of which is:

0.85% of Si, 1.1% of Mg, 0.2% of Fe, 0.32% of Cu, 0.25% of Mn, 0.15% of Cr, 0.16% of Ti, 0.12% of impurities and the balance of Al.

The preparation method is the same as in example 4.

Comparative example 4

The present comparative example provides an aluminum alloy for a building load bearing structure, the formulation of which is:

0.85% of Si, 1.1% of Mg, 0.7% of Fe, 0.32% of Cu, 0.25% of Mn, 0.33% of Cr, 0.16% of Ti, 0.12% of impurities and the balance of Al.

The preparation method comprises the following steps:

(1) preparing various raw materials according to a proportion for later use;

(2) mixing and casting various raw materials to obtain a cast rod;

(3) homogenizing the cast rod;

wherein the homogenizing temperature is 590 ℃, and the time is 4 h;

(4) extruding the homogenized cast rod to obtain a rough blank;

wherein the extrusion temperature is 515 ℃ and the extrusion speed is 5 m/min.

(5) Straightening the rough blank;

wherein, the straightening amount is 0.6 percent;

(6) and carrying out aging treatment on the straightened rough blank to obtain the finished product of the aluminum alloy for the building bearing structure.

Wherein the aging temperature is 170 ℃ and the time is 20 h.

The aluminum alloys for the building bearing structure obtained in the examples 1 to 5 and the comparative examples 1 to 4 are subjected to performance tests, and the specific results are shown in the following table:

the corrosion rate testing method comprises the following steps: respectively taking saturated limewater, simulated acid rain (GSB07-2241-²The surface area of the sample is not less than 20mL), and the corrosion rate is calculated according to the following formula after 5 days of room-temperature corrosion:

and V is 87600 multiplied by delta W/(rho multiplied by S multiplied by t), wherein delta W is the weight loss of the sample, rho is the density of the sample, S is the area of the sample directly contacted with the corrosive environment, t is the corrosion time, and V is the corrosion rate.

Among them, the bonding strength was measured by preparing a concrete block of 15cm × 15cm × 15cm using PO42.5 cement, burying an aluminum alloy rod (diameter 15mm) in the center of the concrete block, and then performing a drawing test (DBJ/T1535).

The specific test results are given in the following table:

while the foregoing is directed to the preferred embodiment of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention.