Cold rolling process of magnesium-copper-aluminum composite sheet

Abstract

The invention discloses a cold rolling process of magnesium-copper-aluminum composite plate, which is specifically implemented according to the following steps: step 1, heat-treating 7075 aluminum alloy, copper and ZK60 magnesium alloy respectively; step 2, degreasing the heat-treated 7075 aluminum alloy, copper and ZK60 magnesium alloy with acetone to remove pollutants; step 3, polishing the acetone-treated 7075 aluminum alloy, copper and ZK60 magnesium alloy; step 4, stacking the polished 7075 aluminum alloy, copper and ZK60 magnesium alloy in order from bottom to top or from bottom to top, and fixing their respective inlet ends and both sides; step 5, placing the stacked and fixed 7075 aluminum alloy, copper and ZK60 magnesium alloy into rolling equipment for room temperature rolling. The invention solves the problems of high environmental requirements and complex process requirements in the existing process for preparing magnesium-aluminum alloy.

Description

Technical Field

[0001] The invention belongs to the technical field of composite material preparation, and in particular relates to a cold rolling process for a magnesium-copper-aluminum composite plate. Background Art

[0002] Magnesium alloys have low plastic forming ability, insufficient rigidity, poor corrosion resistance, and low absolute strength, which greatly limit their large-scale application. Aluminum alloys are currently the most widely used non-ferrous metal structural materials in industrial production, with the characteristics of low density, good formability, high strength, and excellent corrosion resistance. Magnesium-aluminum composite materials combine the advantages of both magnesium alloys and aluminum alloys, and can obtain better comprehensive performance than a single material. They have broad application prospects in aerospace, automobiles, transportation and other fields, and have become a research hotspot in the field of light metals at home and abroad.

[0003] With the development of aerospace technology and the increasing advantages of lightweight alloys in the field of lightweight automobile applications, aluminum-copper-magnesium layered composite materials have been widely used. The promotion of aluminum-copper-magnesium metal laminates is of great significance to solving the current energy structure and lightweight problems. With the growing demand for aluminum-copper-magnesium layered composite sheets in the market, the preparation technology of aluminum-copper-magnesium composite sheets has also made great progress. Aluminum-copper-magnesium layered composite sheets combine the characteristics of low density, high specific strength, and strong surface corrosion resistance, and have physical and chemical properties that single metals do not have.

[0004] From the current research status, the use of spray deposition, reverse solidification, brazing composite and other technical routes has high environmental requirements and complex processes, and cannot guarantee uniform and good metallurgical bonding between materials. Although the interface bonding strength of the layered composite material prepared by powder metallurgy is higher than that of the cast state, its matrix strength and heat resistance are relatively weak, and the process environment requirements are high and difficult to meet. The rolling temperature of traditional magnesium alloys is usually above 300°C. Due to the large difference in plastic deformation capacity between magnesium alloys and aluminum alloys, magnesium alloys and aluminum alloys achieve good metallurgical bonding at the interface, and the rolling temperature is usually above 350°C. Summary of the invention

[0005] The purpose of the present invention is to provide a cold rolling process for magnesium-copper-aluminum composite plates to solve the problems of high environmental requirements and complex process requirements in the existing process for preparing magnesium-aluminum alloys.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is: a cold rolling process of a magnesium-copper-aluminum composite sheet is specifically implemented according to the following steps:

[0007] Step 1, heat treating 7075 aluminum alloy, copper and ZK60 magnesium alloy respectively;

[0008] Step 2, degreasing the heat-treated 7075 aluminum alloy, copper and ZK60 magnesium alloy with acetone to remove contaminants;

[0009] Step 3, grinding the 7075 aluminum alloy, copper and ZK60 magnesium alloy after acetone treatment;

[0010] Step 4, stacking the polished 7075 aluminum alloy, copper and ZK60 magnesium alloy in order from bottom to top or from bottom to top, and fixing their respective inlet ends and both sides;

[0011] Step 5, placing the stacked and fixed 7075 aluminum alloy, copper and ZK60 magnesium alloy into a rolling device for room temperature rolling.

[0012] As a preferred technical solution of the present invention, in step 1, 7075 aluminum alloy is heat treated at 500°C for 4h-6h; copper is heat treated at 600°C for 1h-3h; ZK60 magnesium alloy is heat treated at 410°C for 3h-5h; wherein the heating rate is 2°C / min-4°C / min, and after the insulation is completed, the alloy is cooled to room temperature with the furnace.

[0013] As a preferred technical solution of the present invention, in step 1, the thickness of the 7075 aluminum alloy is 1.0 mm, and the thickness of the copper and ZK60 magnesium alloy is 0.5 mm.

[0014] As a preferred technical solution of the present invention, in step 5, the room temperature rolling is: the first pass reduction is 60%; the second pass reduction is 50%; the third pass reduction is 50%; the fourth pass reduction is 50%; the fifth pass reduction is 50%; the sixth pass reduction is 50%; if there are subsequent passes, the reduction is 50%.

[0015] As a preferred technical solution of the present invention, in step 5, the total thickness of the 7075 aluminum alloy, copper and ZK60 magnesium alloy stacked together is 2 mm. During the room temperature rolling process, the first pass is pressed from 2 mm to 0.8 mm, and the second pass is pressed from 0.8 mm to 0.4 mm.

[0016] The beneficial effects of the present invention are as follows: the cold rolling process of the magnesium-copper-aluminum composite plate of the present invention adopts calendering technology, and during the rolling process, a layer of copper is sandwiched between the ZK60 magnesium alloy and the 7075 aluminum alloy. Both the 7075 aluminum alloy and the ZK60 magnesium alloy are alloys with relatively high strength, and are difficult to combine under room temperature cold rolling in the actual production process. Therefore, a layer of pure copper is used for transition, and the strong bonding ability of pure copper is utilized to realize the metallurgical bonding of dissimilar metals, thereby improving the bonding strength between the 7075 aluminum alloy and the ZK60 magnesium alloy, and ensuring that the magnesium-aluminum layers of the two metals are tightly bonded without stratification under the condition of a large amount of reduction. The finished product has a layer of aluminum alloy attached to its surface, which shows the unique surface treatment ability of aluminum alloy (i.e., not easy to oxidize, with better surface treatment effect, and the density of the composite plate is controlled at. Heat treatment is used to make the material structure more uniform and reduce its strength, which can better regulate the plastic deformation ability of the metal, so that the materials are more closely combined after rolling. The rolling process adopted by the present invention is simple in process and has low requirements on the production environment. The obtained product is mechanically combined, has high tensile strength and heat resistance, and this solution can be used to produce plates with a thickness of 0.5-10mm. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figures 1 to 6 They are schematic diagrams of the effects of magnesium-aluminum-copper composite plates after the first to sixth rolling passes. DETAILED DESCRIPTION

[0018] The technical solution of the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0019] Example 1

[0020] The cold rolling process of the magnesium-copper-aluminum composite plate of the present invention is specifically implemented according to the following steps:

[0021] Step 1, 1mm 7075 aluminum alloy is heat treated at 500℃ for 4h; 0.5mm copper is heat treated at 600℃ for 1h; 0.5mm ZK60 magnesium alloy is heat treated at 410℃ for 3h; the heating rate is 2℃ / min, and after the heat preservation, they are all cooled to room temperature with the furnace;

[0022] Step 2, degreasing the heat-treated 7075 aluminum alloy, copper and ZK60 magnesium alloy with acetone to remove contaminants;

[0023] Step 3, grinding the 7075 aluminum alloy, copper and ZK60 magnesium alloy after acetone treatment;

[0024] Step 4, stacking the polished 7075 aluminum alloy, copper and ZK60 magnesium alloy in order from bottom to top or from bottom to top, and fixing their respective inlet ends and both sides;

[0025] Step 5, placing the stacked and fixed 7075 aluminum alloy, copper and ZK60 magnesium alloy into a rolling equipment for room temperature rolling, the room temperature rolling is: the first pass reduction is 60%; the second pass reduction is 50%; the third pass reduction is 50%; the fourth pass reduction is 50%; the fifth pass reduction is 50%; the sixth pass reduction is 50%; if there are subsequent passes, the reduction is 50%; the total thickness of the 7075 aluminum alloy, copper and ZK60 magnesium alloy stacked together is 2mm, and during the room temperature rolling process, the first pass is pressed from 2mm to 0.8mm, the second pass is pressed from 0.8mm to 0.4mm, the third pass is pressed from 0.4mm to 0.3mm, the fourth pass is pressed from 0.3mm to 0.2mm, the fifth pass is pressed from 0.2mm to 0.1mm, and the sixth pass is pressed from 0.1mm to 0.05mm.

[0026] Combination Figures 1 to 3 It can be observed that from the third pass, the ZK60 layer began to shear and neck, and from the fourth pass, it began to neck and break. The mechanical composite performance was enhanced, effectively improving the mechanical properties of the magnesium plate.

[0027] The performance test was carried out using 7075 aluminum alloy, copper and ZK60 magnesium alloy of the same thickness and the magnesium-copper-aluminum composite plate obtained in Example 1. The results are shown in Table 1:

[0028] Table 1

[0029]

[0030] The cold rolling process of the magnesium-copper-aluminum composite plate of the present invention adopts calendering technology. During the rolling process, a layer of copper is sandwiched between the ZK60 magnesium alloy and the 7075 aluminum alloy. Both the 7075 aluminum alloy and the ZK60 magnesium alloy are alloys with relatively high strength. It is difficult to combine them under cold rolling at room temperature in the actual production process. Therefore, a layer of pure copper is used for transition. The strong bonding ability of pure copper is utilized to realize the metallurgical bonding of dissimilar metals, thereby improving the bonding strength between the 7075 aluminum alloy and the ZK60 magnesium alloy, and ensuring that the magnesium-aluminum layers of the two metals are tightly bonded without stratification under the condition of a large amount of reduction. The finished product has a layer of aluminum alloy attached to its surface, which shows the unique surface treatment ability of aluminum alloy (i.e., it is not easy to oxidize, and has a good surface treatment effect. At the same time, the density of the composite plate is controlled. Heat treatment is used to make the material structure more uniform and reduce its strength, which can better regulate the plastic deformation ability of the metal, so that the materials after rolling are more closely combined. The rolling process adopted by the present invention is simple in process and has low requirements on the production environment. The obtained product is mechanically combined, has high tensile strength and heat resistance, and this solution can be used to produce plates with a thickness of 0.5-10mm.

[0031] Example 2

[0032] like Figure 1 As shown, the cold rolling process of the magnesium-copper-aluminum composite plate of the present invention is specifically implemented according to the following steps:

[0033] Step 1, 1mm 7075 aluminum alloy is heat treated at 500℃ for 5h; 0.5mm copper is heat treated at 600℃ for 2h; 0.5mm ZK60 magnesium alloy is heat treated at 410℃ for 4h; the heating rate is 3℃ / min, and after the heat preservation, they are all cooled to room temperature with the furnace;

[0034] Step 2, degreasing the heat-treated 7075 aluminum alloy, copper and ZK60 magnesium alloy with acetone to remove contaminants;

[0035] Step 3, grinding the 7075 aluminum alloy, copper and ZK60 magnesium alloy after acetone treatment;

[0036] Step 4, stacking the polished 7075 aluminum alloy, copper and ZK60 magnesium alloy in order from bottom to top or from bottom to top, and fixing their respective inlet ends and both sides;

[0037] Step 5, placing the stacked and fixed 7075 aluminum alloy, copper and ZK60 magnesium alloy into a rolling equipment for room temperature rolling, the room temperature rolling is: the first pass reduction is 60%; the second pass reduction is 50%; the third pass reduction is 50%; the fourth pass reduction is 50%; the fifth pass reduction is 50%; the sixth pass reduction is 50%; if there are subsequent passes, the reduction is 50%; the total thickness of the 7075 aluminum alloy, copper and ZK60 magnesium alloy stacked together is 2mm, and during the room temperature rolling process, the first pass is pressed from 2mm to 0.8mm, the second pass is pressed from 0.8mm to 0.4mm, the third pass is pressed from 0.4mm to 0.3mm, the fourth pass is pressed from 0.3mm to 0.2mm, the fifth pass is pressed from 0.2mm to 0.1mm, and the sixth pass is pressed from 0.1mm to 0.05mm.

[0038] Example 3

[0039] like Figure 1 As shown, the cold rolling process of the magnesium-copper-aluminum composite plate of the present invention is specifically implemented according to the following steps:

[0040] Step 1, 1mm 7075 aluminum alloy is heat treated at 500℃ for 6h; 0.5mm copper is heat treated at 600℃ for 3h; 0.5mm ZK60 magnesium alloy is heat treated at 410℃ for 5h; the heating rate is 4℃ / min, and after the heat preservation, they are all cooled to room temperature with the furnace;

[0041] Step 2, degreasing the heat-treated 7075 aluminum alloy, copper and ZK60 magnesium alloy with acetone to remove contaminants;

[0042] Step 3, grinding the 7075 aluminum alloy, copper and ZK60 magnesium alloy after acetone treatment;

[0043] Step 4, stacking the polished 7075 aluminum alloy, copper and ZK60 magnesium alloy in order from bottom to top or from bottom to top, and fixing their respective inlet ends and both sides;

[0044] Step 5, placing the stacked and fixed 7075 aluminum alloy, copper and ZK60 magnesium alloy into a rolling equipment for room temperature rolling, the room temperature rolling is: the first pass reduction is 60%; the second pass reduction is 50%; the third pass reduction is 50%; the fourth pass reduction is 50%; the fifth pass reduction is 50%; the sixth pass reduction is 50%; if there are subsequent passes, the reduction is 50%; the total thickness of the 7075 aluminum alloy, copper and ZK60 magnesium alloy stacked together is 2mm, and during the room temperature rolling process, the first pass is pressed from 2mm to 0.8mm, the second pass is pressed from 0.8mm to 0.4mm, the third pass is pressed from 0.4mm to 0.3mm, the fourth pass is pressed from 0.3mm to 0.2mm, the fifth pass is pressed from 0.2mm to 0.1mm, and the sixth pass is pressed from 0.1mm to 0.05mm.

Claims

1. A cold rolling process for magnesium-copper-aluminum composite sheet, characterized in that: Follow the steps below to implement it: Step 1, heat treating 7075 aluminum alloy, copper and ZK60 magnesium alloy respectively; Step 2, degreasing the heat-treated 7075 aluminum alloy, copper and ZK60 magnesium alloy with acetone to remove contaminants; Step 3, grinding the 7075 aluminum alloy, copper and ZK60 magnesium alloy after acetone treatment; Step 4, stacking the polished 7075 aluminum alloy, copper and ZK60 magnesium alloy in order from bottom to top, and fixing their respective inlet ends and both sides; Step 5, placing the stacked and fixed 7075 aluminum alloy, copper and ZK60 magnesium alloy into a rolling device for room temperature rolling; In the step 1, the 7075 aluminum alloy is heat treated at 500° C. for 4 h-6 h; the copper is heat treated at 600° C. for 1 h-3 h; the ZK60 magnesium alloy is heat treated at 410° C. for 3 h-5 h; wherein the heating rate is 2° C. / min-4° C. / min, and after the heat preservation is completed, the alloy is cooled to room temperature with the furnace; the thickness of the 7075 aluminum alloy is 1.0 mm, and the thickness of the copper and ZK60 magnesium alloy is 0.5 mm; In step 5, the normal temperature rolling is as follows: the first pass has a reduction of 60%; the second pass has a reduction of 50%; the third pass has a reduction of 50%; the fourth pass has a reduction of 50%; the fifth pass has a reduction of 50%; the sixth pass has a reduction of 50%; if there are subsequent passes, the reduction is 50%; The total thickness of the 7075 aluminum alloy, copper and ZK60 magnesium alloy stacked together is 2 mm. During the room temperature rolling process, the first pass is pressed from 2 mm to 0.8 mm, and the second pass is pressed from 0.8 mm to 0.4 mm.

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