CN113477743B

CN113477743B - Aluminum alloy pop can body and processing method thereof

Info

Publication number: CN113477743B
Application number: CN202111046586.1A
Authority: CN
Inventors: 葛玉瑞; 张飞飞; 尹世峰; 王新建; 叶俊
Original assignee: Zouping Hongfa Aluminum Technology Co ltd; Shandong Hongqiao New Material Co Ltd
Current assignee: Binzhou Hongzhan Aluminum Technology Co ltd
Priority date: 2021-09-08
Filing date: 2021-09-08
Publication date: 2021-11-30
Anticipated expiration: 2041-09-08
Also published as: CN113477743A

Abstract

The invention discloses an aluminum alloy pop can body and a processing method thereof, belongs to the field of metal packaging, and particularly relates to the aluminum alloy pop can body which is prepared by deep drawing of a 3104 aluminum alloy plate, wherein the 3104 aluminum alloy plate is Al-Mn-Mg series aluminum alloy, and the plate is prepared by casting, sawing and milling, soaking, hot rolling (rough rolling and finish rolling), cold rolling and trimming. The thickness of the finally prepared 3104 aluminum alloy plate is 0.25-0.26 mm. The 3104 aluminum alloy plate prepared by the method sacrifices a small part of strength, but the elongation is obviously increased, and the large-depth deep-drawing tank can be prepared by deep-drawing for many times. And the soaking shortens the time of the first stage, reduces the heat difference between the first stage and the second stage, reduces the temperature without stopping for waiting, realizes the flow line production, and greatly reduces the use of fossil fuels.

Description

Aluminum alloy pop can body and processing method thereof

Technical Field

The technical scheme of the invention belongs to the field of nonferrous metal processing (aluminum alloy processing) and metal packaging.

Background

With the comprehensive understanding, development and utilization of marine resources by human beings, marine aquaculture becomes a component in marine industry, and plays an important role in marine economic development. With the continuous deepening of fishery industry structures, the deep processing is carried out by utilizing marine fishery resources to form great advantages and characteristics. The canned aquatic product is made up by using fish and other aquatic products as raw material, cooking and dewatering, canning, adding flavouring liquor and sealing and sterilizing, and features no poison to human body, no pollution to food, good sealing performance, long storage period and good corrosion resistance.

3104 the aluminum alloy belongs to Al-Mn-Mg series aluminum alloy, has the characteristics of high strength, high toughness, strong corrosion resistance, good deep drawing formability and the like, and is widely applied to packaging, transportation and production and manufacture of pop can bodies. The sheet material has low anisotropy and earing ratio, which is favorable for deep drawing cans. However, 3104 aluminum alloy is easy to crack after single deep drawing or two or three deep drawing, and cannot meet the requirement of preparing canned food of large fish. Such as subsequent re-welding, affects the storage capacity of the can due to the relatively poor sealing of the weld.

Moreover, most Al-Mn-Mg series antirust aluminum alloy ingots are cast by DC (direct water cooling casting), the distribution of Mn elements is extremely uneven, serious intragranular segregation is formed, and the recrystallization behavior and deep drawing performance of the plate are obviously influenced. Therefore, the ingot needs to be subjected to soaking treatment, segregation inside the alloy is eliminated through diffusion of elements, and the form of the second phase particles needs to be regulated and optimized so as to facilitate subsequent processing.

The existing aluminum alloy soaking process is mainly (590 ℃ -620 ℃) (6 h-12 h) + (490 ℃ -520 ℃) (1 h-3 h), but the process has the defects that: firstly, the soaking time is long, so that the production is discontinuous, and the machine is stopped for waiting about 2-6 hours when three furnaces (25 flat ingots in each furnace) are produced; secondly, the production cost is increased, the heating furnace is heated by natural gas, fossil fuel is consumed, and a large amount of CO is released during combustion₂This is not favorable for achieving the goal of carbon neutralization.

Disclosure of Invention

The method aims at the problems that the deep drawing performance of 3104 aluminum alloy in the prior art is limited, the method cannot be applied to the preparation of a solderless deep drawing tank with large depth, and the soaking step is complex and the energy consumption is large in the preparation process. The invention provides an aluminum alloy pop can body and a processing method thereof.

An aluminum alloy pop can body is formed by deep drawing 3104 aluminum alloy plates; the 3104 aluminum alloy plate comprises the following alloy elements in percentage by weight: 0.24% of Si, Fe: 0.45%, Cu: 0.18%, Mn: 0.90%, Mg: 1.24 percent, less than or equal to 0.05 percent of other elements singly and less than or equal to 0.15 percent of the total; the balance of Al;

wherein, the 3104 aluminum alloy plate is processed by the following method;

(1) smelting, forging and milling the aluminum alloy according to the element proportion to obtain an aluminum alloy ingot;

(2) carrying out two-stage homogenization heat treatment on the aluminum alloy cast ingot: in the first stage, heat treatment is carried out for 2-3h at 590 ℃; in the second stage, the heat preservation treatment is carried out for 1h at the temperature of 550 +/-10 ℃;

(3) carrying out hot rolling on the ingot subjected to the second-stage homogenization heat treatment in the step (2) to obtain a hot rolled plate; the outlet thickness of the hot rolled plate blank is 2.1-2.2 mm;

(4) cold rolling the hot rolled plate blank to roll the plate thickness to 0.250-0.260 mm;

(5) and (6) cutting edges and packaging.

Wherein the hot rolling in the step (3) is hot continuous rolling, and the hot continuous rolling uses 1+4 hot continuous rolling.

Specifically, the 1+4 hot continuous rolling comprises the following steps: firstly, rolling by using a roughing mill for 15-19 times, and processing the cast ingot into an intermediate blank with the thickness of 30 mm; then finish rolling by using a 4-frame hot continuous rolling mill; the hot rolling temperature is 350-360 ℃.

Wherein the cold rolling speed is 800-1100m/min, and the outlet temperature is 130-180 ℃.

As is known in the art, Al-Mn-Mg series aluminum alloy belongs to heat treatment non-strenthenable aluminum alloy, and can only achieve the strengthening purpose by means of cold deformation. The strength of the plate is enhanced along with the increase of the cold deformation, but the texture is also enhanced, thereby leading to the improvement of the earing rate and the reduction of the deep drawing rate. Therefore, the structural strength and the deep drawing performance cannot be simultaneously considered.

The invention shortens the first-stage heat treatment time in soaking to 2-3h, and increases the second-stage heat preservation treatment temperature to 540-555 ℃, thereby greatly reducing energy consumption, reducing the temperature difference between the first stage and the second stage, accelerating the production rhythm and avoiding the time for waiting for temperature during shutdown.

After the soaking treatment of the invention, the size and shape factor (ratio of long axis to short axis of the compound) of the precipitated compound are smaller, and obviously tend to be more spherical, as shown in figure 2.

Fig. 1 and 2 show that the material surface and the internal crystal grains perform better after the soaking process of the invention patent is adopted.

The invention has the beneficial effects

(1) The soaking and heat preservation time of the first stage is shortened to 2-3h, the soaking temperature of the second stage is increased to 540-555 ℃, the hot rolling soaking time is greatly shortened, the natural gas is saved by 90-110m at each furnace on average, and meanwhile, the original soaking process needs to be stopped for waiting for 4h every three furnaces in the production process; greatly reduces energy consumption, accelerates production rhythm and avoids shutdown time for temperature.

(2) Although the aluminum alloy plate provided by the invention sacrifices a small part of strength, the elongation is obviously increased, and a large-depth deep-drawing tank can be prepared by deep-drawing for many times.

Drawings

FIG. 1 is a diagram of an aluminum alloy sheet prepared in example 1 of the present invention;

FIG. 2 is a diagram showing an example of an aluminum alloy sheet according to comparative example 1 of the present invention;

FIG. 3 is a diagram showing an example of an aluminum alloy sheet according to comparative example 2 of the present invention;

FIG. 4 shows a metallographic structure of an aluminum alloy sheet prepared in example 1 of the present invention; scale 50 microns;

FIG. 5 is a metallographic structure of an aluminum alloy sheet prepared in comparative example 1 of the present invention; scale 50 microns;

FIG. 6 is a metallographic structure of an aluminum alloy sheet prepared in comparative example 2 of the present invention; the scale is 50 microns.

Detailed Description

In order to make the technical solutions of the present application better understood, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

Example 1

The aluminum alloy comprises the following elements in percentage by weight: 0.24% of Si, Fe: 0.45%, Cu: 0.18%, Mn: 0.90%, Mg: 1.24 percent, less than or equal to 0.05 percent of other elements, less than or equal to 0.15 percent of the total, and the balance of Al.

The production method comprises the following steps: smelting → casting → sawing → soaking → hot rolling (rough rolling, finish rolling) → trimming → packaging.

Soaking treatment: (600. + -.10). degree.C.3 h + (550. + -.10). degree.C.1 h

And in the hot continuous rolling process, 1+4 hot continuous rolling is adopted, a roughing mill is used for rolling for 15-19 times, and the cast ingot is processed into an intermediate billet with the thickness of 30 mm. Rolling with a 4-stand hot continuous rolling mill, hot rolled billet exit thickness: 2.1-2.2 mm; hot rolling finishing temperature: 350-360 ℃; the cubic texture proportion of the material is improved, the forming performance of the material is improved, and the room-temperature mechanical property of the material is reduced;

the thickness of the cold continuous rolling is rolled to 0.250-0.260mm, the speed is 800-1100m/min, and the outlet temperature of the finished product is 130-.

Comparative example 1

Soaking treatment: 600 ℃/3h +510 ℃/1 h; the rest of the procedure was the same as in example 1.

Comparative example 2

Soaking treatment: 600 ℃/8h +510 ℃/1 h; the rest of the procedure was the same as in example 1.

Numbers 1-3 correspond to example 1, comparative example 2, respectively. Three aluminum alloy sheets were characterized and the measured data were compiled as follows:

TABLE 1 Compound size and shape factor variation after different soaking process treatments

As shown in table 1, the size and shape factor (ratio of long axis to short axis of the compound) of the compound precipitated after the soaking process of the present invention are smaller and significantly more spherical.

TABLE 2 comparison of mechanical properties of different soaking processes

As shown in Table 2, after the soaking process disclosed by the invention is adopted, the mechanical property of the finished product is slightly reduced, the elongation is obviously increased, and the n value (work hardening index) and the r value (plastic strain ratio) are both increased, which indicates that the deep drawing property and the formability of the material are better.

Further, fig. 1 and 2 show that the material surface and the internal crystal grains perform better after the soaking process of the invention is adopted.

Claims

1. An aluminum alloy pop can body is characterized in that the can body is formed by deep drawing of 3104 aluminum alloy plates;

the 3104 aluminum alloy plate comprises the following alloy elements in percentage by weight: 0.24% of Si, Fe: 0.45%, Cu: 0.18%, Mn: 0.90%, Mg: 1.24 percent, less than or equal to 0.05 percent of other elements singly and less than or equal to 0.15 percent of the total; the balance of Al;

the 3104 aluminum alloy plate is processed by the following method;

(1) smelting, casting and milling the aluminum alloy according to the element proportion to obtain an aluminum alloy ingot;

(4) cold rolling the hot rolled plate blank to the thickness of 0.250-0.260 mm;

(5) and (6) cutting edges and packaging.

2. The aluminum alloy can body of claim 1, wherein the hot rolling in step (3) is hot continuous rolling, and 1+4 hot continuous rolling is used for the hot continuous rolling.

3. The aluminum alloy pop can body as claimed in claim 2, wherein the 1+4 hot continuous rolling is specifically as follows: firstly, rolling by using a roughing mill for 15-19 times, and processing the cast ingot into an intermediate blank with the thickness of 30 mm; then finish rolling by using a 4-frame hot continuous rolling mill; the hot rolling temperature is 350-360 ℃.

4. The aluminum alloy can body of claim 1, wherein the cold rolling speed is 800-.