阅读说明：本技术 一种中等强度高导热铝合金及其快速时效工艺 (Medium-strength high-heat-conductivity aluminum alloy and rapid aging process thereof ) 是由 周晶哲 梁豪辉 刘才兴 于 2020-07-22 设计创作，主要内容包括：本发明公开一种中等强度高导热铝合金及其快速时效工艺,包括以下步骤：1)铝合金铸锭制备,按照相应的配方制备6系铝合金铸锭；2)均质化处理,在不同温度下依次进行均质化处理,均质处理后冷却；3)将均质后的铝合金铸锭表面进行表面刷棒或剥皮处理；4)挤压,将刷棒或剥皮好的铝合金铸锭进行头中尾分段加热,随后放入挤压机的挤压筒中进行挤压；5)矫正；6)双级人工时效处理,一级时效温度为230-250℃,一级时效保温时间为1.5-2h,二级时效温度为170-190℃,二级时效保温时间为4-5h。利用本发明制得的铝合金,其热导率能达到215W/(m·K)以上,接近纯铝导热性能,同时其抗拉强度大于195Mpa,屈服强度大于170Mpa,断后延伸率大于8％,远远大于纯铝的力学性能。(The invention discloses a medium-strength high-heat-conductivity aluminum alloy and a rapid aging process thereof, which comprises the following steps: 1) preparing an aluminum alloy ingot, namely preparing a 6-series aluminum alloy ingot according to a corresponding formula; 2) homogenizing, sequentially homogenizing at different temperatures, and cooling; 3) carrying out surface brushing or peeling treatment on the homogenized aluminum alloy cast ingot surface; 4) extruding, namely heating the brush rod or the peeled aluminum alloy cast ingot in a head-to-tail sectional manner, and then putting the heated brush rod or the peeled aluminum alloy cast ingot into an extruding cylinder of an extruder for extruding; 5) correcting; 6) and (3) two-stage artificial aging treatment, wherein the first-stage aging temperature is 230-250 ℃, the first-stage aging heat preservation time is 1.5-2h, the second-stage aging temperature is 170-190 ℃, and the second-stage aging heat preservation time is 4-5 h. The thermal conductivity of the aluminum alloy prepared by the method can reach more than 215W/(m.K), which is close to the thermal conductivity of pure aluminum, and meanwhile, the tensile strength is more than 195MPa, the yield strength is more than 170MPa, and the elongation after fracture is more than 8 percent, which is far more than the mechanical property of pure aluminum.)

1. A medium-strength high-heat-conductivity aluminum alloy and a rapid aging process thereof are characterized by comprising the following steps:

1) preparing an aluminum alloy ingot, namely preparing the aluminum alloy according to the following weight part ratio: si: 0.40-0.45%, Fe: less than or equal to 0.12 percent, Cu: less than or equal to 0.01 percent, Mn: less than or equal to 0.005 percent, Mg: 0.55-0.60%, Zn: less than or equal to 0.03%, B: 0.04-0.06%, Ti: 0.005-0.015%, less than or equal to 0.01% of single impurity, less than or equal to 0.05% of impurity in total, and the balance of Al; then melting and casting the aluminum alloy raw material into an aluminum alloy ingot;

2) homogenizing, homogenizing at 540 + -10 deg.C for 6 + -1 h, heating to 580 + -10 deg.C, homogenizing for 2 + -0.5 h, homogenizing, and cooling;

3) brushing a rod or peeling, namely performing surface brushing or peeling treatment on the surface of the homogenized aluminum alloy cast ingot;

4) extruding, namely heating the brush rod or the peeled aluminum alloy cast ingot in a head-to-tail sectional manner at the rod head temperature of 420-460 ℃, the rod middle temperature of 410-450 ℃ and the rod tail temperature of 400-440 ℃, and then putting the heated brush rod or the peeled aluminum alloy cast ingot into an extruding cylinder of an extruder for extruding;

5) straightening, wherein the extruded section product is straightened after being cooled, and the straightening amount is 0.3-1.0%;

6) and carrying out two-stage artificial aging treatment on the extruded section, wherein the first-stage aging temperature is 230-250 ℃, the first-stage aging heat preservation time is 1.5-2H, the second-stage aging temperature is 170-190 ℃, and the second-stage aging heat preservation time is 4-5H.

2. The medium-strength high-thermal-conductivity aluminum alloy and the rapid aging process thereof as claimed in claim 1, wherein in the step 1) of preparing the aluminum alloy ingot, an aluminum ingot with the purity of more than or equal to 99.8% is used as Al.

3. The medium-strength high-thermal-conductivity aluminum alloy and the rapid aging process thereof as claimed in claim 1, wherein in the step of preparing the aluminum alloy ingot in step 1), when the prepared aluminum alloy raw material is added into a smelting furnace to be melted into molten aluminum, AlTi alloy with the total Ti content of 0.005% is added, and then AlB alloy is added.

4. The medium-strength high-heat-conductivity aluminum alloy and the rapid aging process thereof as claimed in claim 1, wherein in the step of 1) preparing the aluminum alloy ingot, after the aluminum alloy raw material is added, an electromagnetic stirring device is used for uniformly stirring, then a refining agent is used for refining and degassing, then the aluminum alloy ingot is placed for 30-60 minutes to precipitate impurities, then the residual impurities in the aluminum liquid are filtered through a 40-60-mesh ceramic filter plate, and then the aluminum liquid is cast into the aluminum alloy ingot.

5. The medium strength high thermal conductivity aluminum alloy and the rapid aging process thereof as claimed in claim 1, wherein in the step 2) of homogenizing, the homogenizing is followed by cooling by air cooling.

6. The medium-strength high-heat-conductivity aluminum alloy and the rapid aging process thereof as claimed in claim 1, wherein in the step 4) of extruding, the extruding speed of the product is 8-20 m/min, and the temperature of the extruding ingot container is controlled at 390-440 ℃.

7. The medium-strength high-heat-conductivity aluminum alloy and the rapid aging process thereof as claimed in claim 1, wherein in the step 4) of extruding, a variable frequency fan is used for quenching and cooling treatment after extruding.

Technical Field

The invention relates to the technical field of aluminum profile processing and manufacturing, in particular to a medium-strength high-heat-conductivity aluminum alloy and a rapid aging process thereof.

Background

With the development of the aluminum profile industry, higher and higher requirements are also put forward on the performance of the aluminum alloy in various aspects. Particularly for many heat dissipation materials, in addition to the conventional basic mechanical properties, how to improve the heat conductivity of the heat dissipation material to improve the heat dissipation capability is also becoming more and more important. Particularly, in the process of gradually falling to the ground in the 5G communication, the power of the matching element needs to be continuously increased due to the increase of the communication power, but the high power can bring greater heat generation, if the communication element cannot be cooled in time, the communication element can be quickly aged or even burnt, and great adverse effects exist. Therefore, it is more and more important to improve the heat conductivity and heat dissipation of aluminum alloy to match the upgrading requirement of products. Meanwhile, it is also necessary to ensure that the profile does not deform during processing or the finished product can avoid deformation during use, i.e., certain strength and hardness indexes of the alloy performance are required under the condition of high heat conductivity. In order to achieve the comprehensive effect, the components and the internal structure of the material are adjusted, and the design of a heat treatment process is a key direction for improving the comprehensive performance.

Disclosure of Invention

The invention aims to provide a processing technology of a 6-series aluminum alloy profile with medium strength and heat conductivity of more than 215W/(m.K).

In order to achieve the purpose, the invention adopts the following technical scheme.

A medium-strength high-heat-conductivity aluminum alloy and a rapid aging process thereof are characterized by comprising the following steps: 1) preparing an aluminum alloy ingot, namely preparing the aluminum alloy according to the following weight part ratio: si: 0.40-0.45%, Fe: less than or equal to 0.12 percent, Cu: less than or equal to 0.01 percent, Mn: less than or equal to 0.005 percent, Mg: 0.55-0.60%, Zn: less than or equal to 0.03%, B: 0.04-0.06%, Ti: 0.005-0.015%, less than or equal to 0.01% of single impurity, less than or equal to 0.05% of impurity in total, and the balance of Al; then melting and casting the aluminum alloy raw material into an aluminum alloy ingot; 2) homogenizing, homogenizing at 540 + -10 deg.C for 6 + -1 h, heating to 580 + -10 deg.C, homogenizing for 2 + -0.5 h, homogenizing, and cooling; 3) brushing a rod or peeling, namely performing surface brushing or peeling treatment on the surface of the homogenized aluminum alloy cast ingot; 4) extruding, namely heating the brush rod or the peeled aluminum alloy cast ingot in a head-to-tail sectional manner at the rod head temperature of 420-460 ℃, the rod middle temperature of 410-450 ℃ and the rod tail temperature of 400-440 ℃, and then putting the heated brush rod or the peeled aluminum alloy cast ingot into an extruding cylinder of an extruder for extruding; 5) straightening, wherein the extruded section product is straightened after being cooled, and the straightening amount is 0.3-1.0%; 6) and carrying out two-stage artificial aging treatment on the extruded section, wherein the first-stage aging temperature is 230-250 ℃, the first-stage aging heat preservation time is 1.5-2H, the second-stage aging temperature is 170-190 ℃, and the second-stage aging heat preservation time is 4-5H.

More preferably, in the step 1) of preparing the aluminum alloy ingot, an aluminum ingot with the purity of more than or equal to 99.8 percent is used as Al.

More preferably, in the step 1) of preparing the aluminum alloy ingot, when the prepared aluminum alloy raw material is added into a smelting furnace to be melted into molten aluminum, an AlTi alloy with the total Ti content of 0.005% is added, and then an AlB alloy is added.

More preferably, in the step 1) of preparing the aluminum alloy ingot, after the aluminum alloy raw material is added, the aluminum alloy raw material is uniformly stirred by using an electromagnetic stirring device, then a refining agent is used for refining and degassing, standing is carried out for 30-60 minutes to precipitate impurities, then residual impurities in molten aluminum are filtered by a 40-60-mesh ceramic filter plate, and then the molten aluminum is cast into the aluminum alloy ingot.

More preferably, in the homogenization step of step 2), the homogenization treatment is followed by cooling by air cooling.

More preferably, in the step 4), the extrusion speed of the product is 8-20 m/min, and the temperature of the extrusion ingot holding cylinder is controlled at 390-440 ℃.

More preferably, in the step 4), quenching and cooling treatment is carried out by using a variable frequency fan after extrusion.

The invention has the beneficial effects that:

through practical tests, the thermal conductivity of the 6-series aluminum alloy section provided by the invention can reach more than 215W/(m.K), and is close to the thermal conductivity of pure aluminum, and meanwhile, the tensile strength of the 6-series aluminum alloy section is greater than 195MPa, the yield strength of the 6-series aluminum alloy section is greater than 170MPa, and the elongation after fracture is greater than 8%, which is far greater than the mechanical property of pure aluminum. The mechanical property indexes enable the aluminum alloy to be used in the field of a plurality of shell products or products needing deep processing, and the aluminum alloy is not like pure aluminum which cannot be used as a shell or processed due to low strength, but has good heat-conducting property, can greatly accelerate the heat dissipation of equipment, and has great application value.

Detailed Description

The following further describes the embodiments of the present invention, so that the technical solutions and the advantages thereof of the present invention are more clear and definite. The following description of the embodiments is exemplary in nature and is in no way intended to limit the invention.

Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.

A medium-strength high-heat-conductivity aluminum alloy and a rapid aging process thereof are characterized by comprising the following steps:

1) preparing an aluminum alloy ingot, namely preparing the aluminum alloy according to the following weight part ratio: si: 0.40-0.45%, Fe: less than or equal to 0.12 percent, Cu: less than or equal to 0.01 percent, Mn: less than or equal to 0.005 percent, Mg: 0.55-0.60%, Zn: less than or equal to 0.03%, B: 0.04-0.06%, Ti: 0.005-0.015%, less than or equal to 0.01% of single impurity, less than or equal to 0.05% of impurity in total, and the balance of Al. Wherein, Al must use aluminum ingot with purity more than or equal to 99.8 percent, and does not allow to use recycled aluminum waste, the prepared aluminum alloy raw material is added into a smelting furnace to be melted into aluminum liquid, wherein AlTi alloy with the total Ti content of 0.005 percent is added firstly, then AlB alloy is added, the method aims to promote the combination with Zr, V and other elements to form compounds, avoid the problem that the compounds cannot be combined with B elements because of less impurity components, use an electromagnetic stirring device to stir uniformly after the addition, use a refining agent to refine and degas, then stand for 30-60 minutes to precipitate impurities, then filtering residual impurities in the molten aluminum by a 40-60 mesh ceramic filter plate, casting the molten aluminum into an aluminum alloy ingot, wherein the purpose of the standing treatment is to ensure that impurity components in the aluminum liquid fully react with Ti and B to generate a heavier impurity polymer which is precipitated to the bottom in the standing process, so as to reduce the influence of the compound composed of the impurity components in the matrix and improve the heat-conducting property.

2) Homogenizing at 540 +/-10 deg.c for 6 +/-1 hr, heating to 580 +/-10 deg.c, homogenizing for 2 +/-0.5 hr, and air cooling.

3) And (3) brushing rods or peeling, namely brushing rods or peeling the surfaces of the homogenized aluminum alloy ingots, so as to avoid influence on heat conductivity caused by the profile due to the fact that impurities of a surface segregation layer are rolled in the extrusion process.

4) And extruding, namely heating the brush rod or the peeled aluminum alloy ingot in a head-to-tail sectional manner at the rod head temperature of 420-460 ℃, the rod middle temperature of 410-450 ℃ and the rod tail temperature of 400-440 ℃ respectively, putting the heated aluminum alloy ingot or the peeled aluminum alloy ingot into an extruding cylinder of an extruder for extruding, wherein the extruding speed of a product is 8-20 m/min, the temperature of an extruding and ingot containing cylinder is controlled at 390-440 ℃, and the purpose is to reduce the entrainment of impurities in a segregation layer on the surface of the ingot in the extruding process and carry out quenching and cooling treatment by using a variable frequency fan after the extruding.

5) And (3) straightening, wherein the extruded profile product is straightened after being cooled, the straightening amount is 0.3-1.0%, the straightening amount must be controlled, the situation that the internal stress of the profile cannot be released due to too small straightening amount is avoided, and meanwhile, the influence on the heat conduction performance caused by severe dislocation defect formed by cold deformation due to too long straightening length is also avoided.

6) The two-stage artificial aging treatment is carried out on the extruded section, the first-stage aging temperature is 230-.

Through practical tests, the heat conductivity of the aluminum alloy section produced by adopting the processing mode can reach more than 215W/(m.K), and is close to the heat conductivity of pure aluminum, and meanwhile, the tensile strength of the aluminum alloy section is greater than 195MPa, the yield strength of the aluminum alloy section is greater than 170MPa, and the elongation after fracture is greater than 8%, which is far greater than the mechanical property of pure aluminum. The mechanical property indexes enable the aluminum alloy to be used in the field of a plurality of shell products or products needing deep processing, and the aluminum alloy is not like pure aluminum which cannot be used as a shell or processed due to low strength, but has good heat-conducting property, can greatly accelerate the heat dissipation of equipment, and has great application value.

It will be understood by those skilled in the art from the foregoing description that the present invention is not limited to the specific embodiments described above, and that modifications and substitutions based on the known art are intended to be included within the scope of the present invention as defined by the appended claims and their equivalents. The details not described in the detailed description are prior art or common general knowledge.