JP6774200B2 - Manufacturing method of Al-Mg-Si based alloy plate - Google Patents

Description

The present invention relates to a method for producing an Al—Mg—Si based alloy plate, particularly a method for producing an Al—Mg—Si based alloy plate having excellent thermal conductivity, conductivity, strength and workability.

Heat generators such as flat-screen TVs, flat-screen monitors for personal computers, laptop computers, tablet computers, car navigation systems, portable navigation systems, chassis of products such as mobile terminals such as smartphones and mobile phones, metal-based printed circuit boards, and internal covers. The member material to be built in or mounted is required to have excellent thermal conductivity, strength and workability for quick heat dissipation.

Pure aluminum alloys such as JIS1100, 1050, and 1070 have excellent thermal conductivity, but have low strength. Al-Mg alloys (5000 series alloys) such as JIS5052 used as high-strength materials are significantly inferior in thermal conductivity and conductivity to pure aluminum alloys.

On the other hand, the Al-Mg-Si alloy (6000 alloy) has good thermal conductivity and conductivity, and the strength can be improved by aging curing. Therefore, the strength and heat of the Al-Mg-Si alloy are used. A method for obtaining an aluminum alloy plate having excellent conductivity and workability is being studied.

For example, Patent Document 1 contains 0.1 to 0.34% by mass of Mg, 0.2 to 0.8% by mass of Si, 0.22 to 1.0% by mass of Cu, and the balance is Al and An Al-Mg-Si alloy composed of unavoidable impurities and having a Si / Mg content ratio of 1.3 or more is semi-continuously cast into an ingot having a thickness of 250 mm or more and preheated at a temperature of 400 to 540 ° C. A method for producing an Al—Mg—Si alloy rolled plate, which comprises hot rolling, cold rolling at a rolling reduction of 50 to 85%, and then annealing at a temperature of 140 to 280 ° C. It is disclosed.

Patent Document 2 contains Si: 0.2 to 1.5% by mass, Mg: 0.2 to 1.5% by mass, Fe: 0.3% by mass or less, and Mn: 0.02 to 0.02 to It contains one or two kinds of 0.15% by mass and Cr: 0.02 to 0.15%, and the balance is Al and Ti in unavoidable impurities is regulated to 0.2% or less, or to this. An aluminum alloy plate having a composition containing 1 or 2 types of Cu: 0.01 to 1% by mass or rare earth element: 0.01 to 0.2% by mass is produced by continuous casting and rolling, and then cold-rolled. Then, a solution treatment at 500 to 570 ° C. is performed, followed by a cold rolling at a cold rolling rate of 5 to 40%, and after the cold rolling, an aging treatment is performed in which the material is heated to less than 150 to 190 ° C. A method for producing an aluminum alloy plate having excellent thermal conductivity, strength and bending workability is described.

Patent Document 3 contains Si: 0.2 to 0.8% by mass, Mg: 0.3 to 1% by mass, Fe: 0.5% by mass or less, Cu: 0.5% by mass or less, and further. It contains at least one of Ti: 0.1% by mass or less or B: 0.1% by mass or less, and is composed of the balance Al and unavoidable impurities, or Mn and Cr as impurities are Mn: 0.1% by mass. % Or less, Cr: 0.1% by mass or less is a method for producing an alloy plate, which comprises a step of hot rolling an Al—Mg—Si based alloy ingot and further cold rolling. A method for producing an Al—Mg—Si based alloy plate, which comprises performing a heat treatment by holding at 200 to 400 ° C. for 1 hour or more after the inter-rolling until the end of the cold rolling is shown.

As described in Patent Document 3, in the JIS1000 series to 7000 series aluminum alloys, the thermal conductivity and the conductivity show a good correlation, and the aluminum alloy plate having excellent thermal conductivity has excellent conductivity. Can be used as a conductive member material as well as a heat radiating member material.

Japanese Unexamined Patent Publication No. 2012-62517 Japanese Unexamined Patent Publication No. 2007-9262 Japanese Unexamined Patent Publication No. 2003-321755

However, the improvement in the tensile strength of the rolled alloy plate obtained by the manufacturing method described in Patent Document 1 is largely due to the alloy composition, and the study of the process conditions is insufficient. Further, the chemical composition of the alloy rolled plate specified in Patent Document 1 contains a relatively large amount of Cu, and the element next to Al is Si or Cu, and the content of Mg is relatively small, Si and Mg. Does not include alloys containing approximately the same proportion.

In Patent Document 2, although an aluminum alloy plate having relatively high strength can be obtained, the conductivity described in Examples is lower than that of the alloy plate described in Patent Document 1. Further, in Patent Document 2, high strength can be obtained by subjecting an aluminum alloy plate in the middle of cold rolling to a solution treatment consisting of a high temperature heat treatment of 500 ° C. or higher and then quenching, and then cold rolling. This is because the post-aging treatment is performed, but the solution treatment increases the cost.

In Patent Document 3, an Al—Mg—Si based alloy plate having a higher strength than that in Patent Document 1 can be obtained, but the final path of hot rolling (corresponding to hot finish rolling in Patent Document 3) has not been examined. , It is hard to say that the examination of process conditions is sufficient.

In view of the above-mentioned technical background, the present invention can further improve the strength while having high conductivity and good processability without applying a solution treatment in a step after hot rolling. An object of the present invention is to provide a method for producing an Mg—Si based alloy plate.

The above problem is solved by the following means.
(1) Si: 0.2 to 0.8% by mass, Mg: 0.3 to 1% by mass, Fe: 0.5% by mass or less, Cu: 0.5% by mass or less, and Ti: 0. . Hot rolling and cold rolling are sequentially carried out on an Al—Mg—Si alloy ingot containing at least 1 mass% or less or B: 0.1 mass% or less and composed of the balance Al and unavoidable impurities. A method for manufacturing an alloy plate, in which the surface temperature of the Al-Mg-Si alloy plate immediately after the completion of hot rolling is 230 ° C. or lower, and 200 ° C. or higher after the completion of hot rolling and before the completion of cold rolling. A method for producing an Al-Mg-Si alloy plate that is heat-treated at a temperature of 400 ° C. or lower.
(2) The method for producing an Al—Mg—Si based alloy plate according to item 1 above, wherein Mn, Cr, and Zn as impurities are each regulated to 0.1% by mass or less.
(3) The Al—Mg—Si alloy plate according to the above item 1 or 2, wherein Ni, V, Ga, Pb, Sn, Bi and Zr as impurities are regulated to 0.05% by mass or less, respectively. Production method.
(4) The method for producing an Al—Mg—Si based alloy plate according to any one of the above items 1 to 3, wherein Ag as an impurity is regulated to 0.05% by mass or less.
(5) The method for producing an Al—Mg—Si based alloy plate according to any one of the above items 1 to 4, wherein the total content of rare earth elements as impurities is regulated to 0.1% by mass or less.
(6) The method for producing an Al—Mg—Si based alloy plate according to any one of the above items 1 to 5, wherein the heat treatment is carried out after the completion of hot rolling and before the start of cold rolling.
(7) The method for producing an Al-Mg-Si alloy plate according to any one of Items 1 to 6 above, wherein the surface temperature of the Al—Mg—Si alloy plate immediately after the completion of hot rolling is 200 ° C. or less. ..
(8) The method for producing an Al—Mg—Si based alloy plate according to any one of the above items 1 to 7, wherein the heat treatment temperature is 200 ° C. or higher and 300 ° C. or lower.
(9) The method for producing an Al—Mg—Si based alloy plate according to any one of the above items 1 to 8, wherein the rolling ratio of cold rolling after heat treatment is 20% or more.
(10) The method for producing an Al—Mg—Si based alloy plate according to any one of the above items 1 to 9, wherein the final annealing is performed after cold rolling.
(11) The method for producing an Al—Mg—Si based alloy plate according to item 10 above, wherein the final annealing temperature is 200 ° C. or lower.
(12) Of the plurality of hot rolling passes, the surface temperature of the Al—Mg—Si alloy plate immediately before the pass is 470 to 350 ° C., and the pass cools the Al—Mg—Si alloy plate or the pass. The method for producing an Al—Mg—Si alloy plate according to any one of the above items 1 to 11, wherein the pass in which the average cooling rate by forced cooling after the pass is 50 ° C./min or more is carried out at least once.

According to the invention described in the preceding paragraph (1), Si: 0.2 to 0.8% by mass, Mg: 0.3 to 1% by mass, Fe: 0.5% by mass or less, and Cu: 0.5% by mass. Hot in an Al—Mg—Si alloy ingot containing the following, and further containing at least one of Ti: 0.1% by mass or less or B: 0.1% by mass or less, and consisting of the balance Al and unavoidable impurities. A method for manufacturing an alloy plate in which rolling and cold rolling are sequentially carried out. The surface temperature of the Al-Mg-Si alloy plate immediately after the completion of hot rolling is 230 ° C. or less, and after the completion of hot rolling. Since heat treatment is performed at a temperature of 200 ° C. or higher and lower than 400 ° C. before the end of cold rolling, an effective quenching effect can be obtained by hot rolling, conductivity is improved during heat treatment, and processing and hardening are performed by subsequent cold rolling. By doing so, it is possible to produce an Al—Mg—Si based alloy plate having high values of tensile strength and conductivity and good workability.

According to the invention described in the previous section (2), since Mn, Cr, and Zn as impurities are each regulated to 0.1% by mass or less, the tensile strength and the conductivity are high and the workability is high. It is possible to produce an Al-Mg-Si based alloy plate having a good quality.

According to the invention described in the preceding paragraph (3), Ni, V, Ga, Pb, Sn, Bi and Zr as impurities are regulated to 0.05% by mass or less, respectively, so that the tensile strength and the conductivity are restricted. It is possible to manufacture an Al-Mg-Si based alloy plate having a high value and good workability.

According to the invention described in the previous section (4), since Ag as an impurity is regulated to 0.05% by mass or less, Al-Mg- showing high values of tensile strength and conductivity and good workability. A Si-based alloy plate can be manufactured.

According to the invention described in the preceding paragraph (5), since the total content of rare earth elements as impurities is regulated to 0.1% by mass or less, the tensile strength and conductivity are high and the workability is good. Al-Mg-Si based alloy plate can be manufactured.

According to the invention described in the previous section (6), since the heat treatment is performed after the completion of hot rolling and before the start of cold rolling, work hardening is performed by subsequent cold rolling to obtain tensile strength and conductivity. An Al-Mg-Si based alloy plate having a high rate and good workability can be produced.

According to the invention described in the preceding paragraph (7), since the surface temperature of the Al—Mg—Si alloy plate immediately after the completion of hot rolling is 200 ° C. or lower, the quenching effect by hot rolling can be enhanced.

According to the invention described in the previous item (8), since the heat treatment temperature is 200 ° C. or higher and 300 ° C. or lower, the conductivity and strength can be reliably improved.

According to the invention described in the previous section (9), since the rolling ratio of cold rolling after heat treatment is 20% or more, the strength of the Al—Mg—Si alloy plate is improved by cold rolling and good processing is performed. You can get sex.

According to the invention described in the previous item (10), since the final annealing is performed after cold rolling, the workability of the Al—Mg—Si alloy plate is good.

According to the invention described in the previous section (11), since the final annealing temperature is 200 ° C. or lower, an Al—Mg—Si alloy plate having high tensile strength and conductivity and good workability can be manufactured. can do.

According to the invention described in the previous section (12), among the plurality of hot rolling passes, the surface temperature of the Al-Mg-Si alloy plate immediately before the pass is 470 to 350 ° C. Since the cooling of the system alloy plate or the pass in which the average cooling rate by the pass and the forced cooling after the pass is 50 ° C./min or more is carried out at least once, the quenching effect by hot rolling can be enhanced.

In the method for producing an Al-Mg-Si based alloy plate in which hot rolling and cold rolling are sequentially performed, the inventor of the present application sets the surface temperature of the alloy plate after hot rolling to a predetermined temperature or lower and is hot. It has been found that an Al-Mg-Si alloy plate having high conductivity and high strength can be obtained by performing a heat treatment after the end of rolling and before the end of cold rolling. It led to the invention.

The method for producing the Al—Mg—Si based alloy plate of the present application will be described in detail below.

In the Al—Mg—Si based alloy composition of the present application, the purpose of adding each element and the reason for limiting the content are as follows.

Mg and Si are elements necessary for developing strength, and their respective contents are Si: 0.2% by mass or more and 0.8% by mass or less, and Mg: 0.3% by mass or more and 1% by mass or less. If the Si content is less than 0.2% by mass or the Mg content is less than 0.3% by mass, sufficient strength cannot be obtained. On the other hand, when the Si content exceeds 0.8% by mass and the Mg content exceeds 1% by mass, the rolling load in hot rolling increases, the productivity decreases, and the molding processability of the obtained aluminum alloy plate also increases. become worse. The Si content is preferably 0.2% by mass or more and 0.6% by mass or less, and more preferably 0.32% by mass or more and 0.60% by mass or less. The Mg content is preferably 0.4% by mass or more and 1.0% by mass or less, more preferably 0.45% by mass or more and 0.9% by mass or less, and particularly preferably 0.45% by mass or more and 0.55% by mass or less. preferable.

Fe and Cu are necessary components for molding, but if they are contained in a large amount, the corrosion resistance is lowered. In the present application, the Fe content and the Cu content are each regulated to 0.5% by mass or less. The Fe content is preferably regulated to 0.35% by mass or less, and more preferably 0.1% by mass or more and 0.25% by mass or less. The Cu content is preferably 0.2% by mass or less, and more preferably 0.1% by mass or less.

Ti and B have the effect of refining the crystal grains and preventing solidification cracking when the alloy is cast into the slab. The effect is obtained by the addition of at least one of Ti or B, and both may be added. However, if it is contained in a large amount, a large amount of crystallized products having a large size are produced, so that the processability, thermal conductivity and conductivity of the product are lowered. The Ti content is preferably 0.1% by mass or less, more preferably 0.005% by mass or more and 0.05% by mass or less.

The B content is preferably 0.1% by mass or less, and particularly preferably 0.06% by mass.

Further, although various impurity elements are inevitably contained in the alloy element, Mn and Cr reduce the conductivity and conductivity, and the amount of Zn is small because the corrosion resistance of the alloy material is lowered as the content is increased. preferable. The content of each of Mn, Cr, and Zn as impurities is preferably 0.1% by mass or less, and more preferably 0.05% by mass or less.

Examples of other impurity elements other than the above include, but are not limited to, Ni, V, Ga, Pb, Sn, Bi, Zr, Ag, rare earths, etc., and among these other impurity elements, rare earths Other than the above, the content of each element is preferably 0.05% by mass or less. Among the above other impurity elements, the rare earth element may contain one or more kinds of elements, or may be derived from a casting raw material contained in the state of mischmetal, but contains the total amount of rare earth elements. The amount is preferably 0.1% by mass or less, and more preferably 0.05% by mass or less.

Next, a processing step for obtaining the Al—Mg—Si based alloy plate specified in the present application will be described.

The dissolved components are adjusted by a conventional method to obtain an Al—Mg—Si based alloy ingot. It is preferable that the obtained alloy ingot is homogenized as a step prior to heating before hot rolling.

The homogenization treatment is preferably performed at 500 ° C. or higher.

The heating before hot rolling is carried out in order to solid-solve the crystals, Mg and Si in the Al—Mg—Si alloy ingot to form a uniform structure, but if the temperature is too high, the part in the ingot is partially heated. It is preferable to carry out the process at 450 ° C. or higher and 580 ° C. or lower, and particularly preferably at 500 ° C. or higher and 580 ° C. or lower.

The Al—Mg—Si alloy ingot may be homogenized and then cooled and preheated before hot rolling, or homogenized and preheated before hot rolling may be continuously performed. In the preferable temperature range of the homogenization treatment and the pre-hot rolling heating, the homogenization treatment and the pre-hot rolling heating may be combined and heated at the same temperature.

After casting, before hot rolling, before heating, it is preferable to face-cut the ingot in order to remove the impurity layer near the surface of the ingot. The face cutting may be performed after casting and before homogenization treatment, or after homogenization treatment and before hot rolling and before heating.

Before hot rolling Hot rolling is performed on the Al—Mg—Si alloy ingot after heating.

Hot rolling consists of rough hot rolling and finishing hot rolling. After performing rough hot rolling consisting of multiple passes using a rough hot rolling machine, a finishing hot rolling machine different from the rough hot rolling machine Is used for finishing hot rolling. In the present application, when the final pass in the rough hot rolling mill is the final pass for hot rolling, the finishing hot rolling can be omitted.

In the present application, finish hot rolling is performed once by introducing an Al-Mg—Si alloy plate from one direction using a rolling mill in which one set of upper and lower work rolls or two or more sets of work rolls are continuously installed. It is carried out with the pass of.

When cold rolling is carried out with a coil, the Al—Mg—Si based alloy plate after the finish hot rolling may be wound by a winding device to form a hot-rolled coil. When the final hot rolling is omitted and the final pass of the rough hot rolling is the final pass of the hot rolling, the Al—Mg—Si alloy plate is wound by a winding device after the rough hot rolling. It may be a hot-rolled coil.

In rough hot rolling, after the state in which Mg and Si are solid-solved according to the solution heat treatment is maintained, the Al-Mg—Si alloy plate is cooled by the rough hot rolling pass, or the rough hot rolling is performed. The effect of quenching can be obtained by the temperature drop after the pass and due to the forced cooling after the pass.

In the present application, among the plurality of passes of rough hot rolling, the surface temperature of the Al—Mg—Si alloy plate immediately before the pass is 350 ° C. or higher and 470 ° C. or lower, and the Al—Mg—Si alloy plate is cooled by the pass, or A pass and a pass in which the average cooling rate by forced cooling after the pass is 50 ° C./min or more is called a control pass. The surface temperature of the Al-Mg-Si alloy plate immediately before the control pass was set to 350 ° C or higher and 470 ° C or lower because the effect of quenching by quenching in rough hot rolling is small below 350 ° C and the temperature is higher than 470 ° C. This is because it is difficult to quench the Al-Mg-Si alloy plate after passing.

The average cooling rate is the Al-Mg—Si alloy from the start to the end of the control path when forced cooling is not performed in the control path, and from the start to the end of forced cooling when forced cooling is performed after the control pass. It shall be the value obtained by dividing the temperature drop (° C) of the plate by the required time (minutes).

The forced cooling after the control pass may be carried out sequentially on the rolled portion while rolling the Al—Mg—Si alloy plate, or after rolling the entire Al—Mg—Si alloy plate. May be good. The method of forced cooling is not limited, but water cooling, air cooling, or coolant may be used.

The control pass is preferably performed at least once, and may be performed a plurality of times. When the control path is executed a plurality of times, it is possible to select whether or not to perform forced cooling after the control path for each control path. Immediately before the pass If the surface temperature of the Al-Mg—Si alloy plate is 470 to 350 ° C and the cooling rate is 50 ° C / min or more, the control pass can be performed multiple times, but one control pass is required. By lowering the temperature of the Al—Mg—Si based alloy plate to less than 350 ° C., quenching can be performed efficiently and effectively.

In the present application, when forced cooling is not performed after the final pass of the rough hot rolling, the surface temperature of the Al—Mg—Si based alloy plate immediately after the final pass of the hot rolling is set as the rough hot rolling rising temperature, and the rough hot rolling. When forced cooling is performed after the final pass of rolling, the surface temperature of the Al—Mg—Si based alloy plate immediately after the completion of forced cooling is set as the crude hot rolling rise temperature.

In the present application, when the finish hot rolling is carried out, the finish hot rolling is completed, and when the finish hot rolling is not carried out, the end of the final pass of the rough hot rolling is regarded as the end of the hot rolling, and immediately after the end of the hot rolling. The surface temperature of the Al—Mg—Si based alloy plate shall be 230 ° C. or lower. An effective quenching effect can be obtained by setting the temperature of the alloy plate immediately after the completion of hot rolling to 230 ° C. or lower.

If the surface temperature of the Al-Mg-Si alloy plate immediately after the end of hot rolling is too high, the effect of quenching will be insufficient, and the strength will be improved even if heat treatment is performed after the end of hot rolling and before the end of cold rolling. Is insufficient. The surface temperature of the Al—Mg—Si alloy plate immediately after the completion of hot rolling is preferably 200 ° C. or lower, more preferably 150 ° C. or lower, and particularly preferably 130 ° C. or lower.

When performing hot rolling after rough hot rolling, the surface temperature of the Al-Mg—Si alloy plate immediately before hot rolling is set in order to obtain the quenching effect due to the pass of hot rolling. It is preferably 270 ° C. or lower.

Similarly, when the final pass of rough hot rolling is not the control pass without performing finish hot rolling, the surface temperature of the Al—Mg—Si alloy plate immediately before the final pass of rough hot rolling is 270 ° C or lower. preferable.

On the other hand, when the final pass of rough hot rolling is the control pass without performing finish hot rolling, the control pass is the final pass of hot rolling, so the Al-Mg-Si system immediately before the final pass of hot rolling. Control path so that the surface temperature of the alloy plate is 470-350 ° C and the surface temperature of the alloy plate is 230 ° C or less at a cooling rate of 50 ° C / min or more by rolling or rolling and forced cooling after rolling. To carry out.

Mg ₂ Si is finely and uniformly precipitated on the Al—Mg—Si alloy plate after the completion of hot rolling and before the completion of cold rolling, and the machining strain existing in the Al—Mg—Si alloy plate is reduced. Heat treatment is performed for the purpose of making it.

In the present application, the heat treatment of the Al—Mg—Si alloy plate after the completion of hot rolling and before the completion of cold rolling is carried out at a temperature of 200 ° C. or higher and 400 ° C. or lower in order to obtain the effect of improving the conductivity. If the heat treatment temperature is less than 200 ° C., there is a limit to the improvement of conductivity, and if the heat treatment temperature exceeds 400 ° C., coarse precipitates are formed and high strength and good molding processability of the final product cannot be obtained. Further, when the temperature is 450 ° C. or higher, the coarseness of the recrystallized grains adversely affects the moldability of the final product. The temperature of the heat treatment is preferably 200 ° C. or higher and 300 ° C. or lower, and more preferably 210 ° C. or higher and 280 ° C. or lower.

The time of the heat treatment of the Al—Mg—Si alloy plate to be carried out after the completion of the hot rolling and before the completion of the cold rolling is not particularly limited, but the time may be adjusted at a predetermined temperature in order to improve the conductivity, for example. , The heat treatment may be carried out by adjusting the time in the range of 1 to 12 hours.

After the heat treatment, cold rolling is performed to work harden and further improve the strength.

The heat treatment is preferably carried out after the end of hot rolling and before the start of cold rolling in order to enhance the effect of improving the strength of the Al—Mg—Si based alloy plate by cold rolling.

After the heat treatment, cold rolling is performed to obtain an Al—Mg—Si based alloy plate having a predetermined thickness. Cold rolling after the heat treatment is preferably carried out at a rolling ratio of 20% or more in order to improve the strength. The rolling ratio of the Al—Mg—Si alloy plate by cold rolling after the heat treatment is more preferably 30% or more, and particularly preferably 60% or more.

If necessary, the Al—Mg—Si alloy plate after cold rolling may be washed.

When the workability of the Al—Mg—Si alloy plate is more important, final annealing may be performed after cold rolling. The final annealing is preferably carried out at 200 ° C. or lower, and more preferably 180 ° C. or lower, particularly 160 ° C. or lower, in order to prevent the strength of the Al—Mg—Si alloy plate from becoming too low.

The final annealing time of the Al—Mg—Si alloy plate may be adjusted so as to obtain the required workability and strength, and may be selected, for example, in the range of 1 to 10 hours depending on the final annealing temperature.

The Al—Mg—Si alloy plate of the present application may be produced by a coil or a single plate. Further, the alloy plate may be cut in an arbitrary step after cold rolling and the step after cutting may be performed on a single plate, or slits may be formed depending on the application.

Examples and comparative examples of the present invention are shown below.

Aluminum alloy slabs having different chemical compositions shown in Table 1 were obtained by a DC casting method. For the ingot having a chemical composition number 20 containing rare earths, a raw material containing mischmetal was used for casting.

[Example 1]
The aluminum alloy slab having the chemical composition No. 1 in Table 1 was face-cut. Next, the alloy slab after face cutting was subjected to a homogenization treatment at 570 ° C. for 5 hours in a heating furnace, and then the temperature was changed in the same furnace to perform hot rolling preheating at 540 ° C. for 4 hours. Before hot rolling After heating, the slab at 540 ° C. was taken out from the heating furnace, and rough hot rolling was started. After the thickness of the alloy plate during rough hot rolling is 25 mm, the final pass of rough hot rolling is carried out from the alloy plate temperature of 460 ° C immediately before the pass to an average cooling rate of 80 ° C / min. An alloy plate having a rolled-up temperature of 242 ° C and a thickness of 12 mm was used. In the final pass of rough hot rolling, the alloy plate was moved while rolling, and forced cooling by water cooling was performed by sequentially spraying water on the alloy plate from above and below to the portion of the alloy plate after rolling.

After the rough hot rolling, the alloy plate was subjected to the finish hot rolling from the temperature immediately before the finish hot rolling at 240 ° C. to obtain an alloy plate having a thickness of 7.0 mm. The temperature of the alloy plate immediately after hot rolling was 130 ° C. After the alloy plate after the finish hot rolling was heat-treated at 215 ° C. for 2 hours, cold rolling with a rolling ratio of 98% was carried out to obtain an aluminum alloy plate having a product plate thickness of 0.15 mm.

[Examples 2-41, Comparative Examples 1-6]
After surface-cutting the aluminum alloy slabs shown in Table 1, the treatment was performed under the conditions shown in Tables 2 to 6 to obtain an aluminum alloy plate. As in Example 1, in all Examples and Comparative Examples, homogenization treatment and pre-hot rolling heating were continuously performed in the same furnace, and forced cooling after the final pass of rough hot rolling was performed while rolling. The selection was made from water cooling in which the alloy plate was moved and water was sequentially sprayed onto the alloy plate from above and below on the part of the alloy plate after rolling, air cooling in which air cooling was performed after the final pass of rough hot rolling was completed, and no forced cooling. In some examples, final annealing was performed after cold rolling.

In Example 14, the final pass of the rough hot rolling was set as the final pass of the hot rolling, and the finishing hot rolling was not carried out.

The tensile strength, conductivity, and workability of the obtained alloy plate were evaluated by the following methods.

The tensile strength was measured by a conventional method at room temperature for the JIS No. 5 test piece.

The conductivity was determined as internationally adopted have been annealed standard soft copper (volume resistivity 1.7241 × ^{10 -2} μΩm) relative value when the conductivity was set to 100% IACS of (% IACS).

For workability, the bending angle is 90 °, the thickness of each alloy plate is bent inside radius when the thickness of the alloy plate is 0.4 mm or more, and the bending inside when the thickness of the alloy plate is less than 0.4 mm. A bending test was carried out by the 6.3 V block method of the JIS Z 2248 metal material bending test method with the radius set to 0, and those without cracks were evaluated as ◯, and those with cracks were evaluated as ×.

The evaluation results of tensile strength, conductivity, and workability are shown in Tables 2 to 6.

It has the chemical composition specified in the present application, the surface temperature of the alloy plate immediately after the end of hot rolling is 230 ° C or less, and the heat treatment temperature after the end of hot rolling and before the end of cold rolling is within the range of 200 ° C or more and 400 ° C or less. In one example, the tensile strength and conductivity are high and the workability is good, whereas the chemical composition specified in the present application, the surface temperature of the alloy plate immediately after the end of hot rolling, or the cooling after the end of hot rolling. In the comparative example in which at least one of the heat treatment temperatures before the end of inter-rolling does not satisfy the specified range of the present application, at least either the tensile strength or the conductivity is inferior to that of the examples, and some are inferior in processability.

Claims (12)

Si: 0.2 to 0.8% by mass, Mg: 0.3 to 1% by mass, Fe: 0.5% by mass or less, Cu: 0.5% by mass or less, and Ti: 0.1% by mass. % Or less or B: 0.1% by mass or less of an alloy plate in which hot rolling and cold rolling are sequentially carried out on an Al—Mg—Si based alloy ingot containing at least one kind and consisting of the balance Al and unavoidable impurities. In the manufacturing method, heating before hot rolling is carried out at 500 ° C. or higher and 580 ° C. or lower, and the surface temperature of the Al—Mg—Si alloy plate immediately after the completion of hot rolling is 230 ° C. or lower, which is higher than that of hot rolling. A method for producing an Al—Mg—Si alloy plate, which is heat-treated at a temperature of 200 ° C. or higher and 400 ° C. or lower after the completion of hot rolling and before the completion of cold rolling without performing solution treatment in a later step. .. The method for producing an Al—Mg—Si based alloy plate according to claim 1, wherein Mn, Cr, and Zn as unavoidable impurities are each regulated to 0.1% by mass or less. The Al—Mg—Si alloy plate according to claim 1 or 2, wherein Ni, V, Ga, Pb, Sn, Bi and Zr as unavoidable impurities are regulated to 0.05% by mass or less, respectively. Production method. The method for producing an Al—Mg—Si based alloy plate according to any one of claims 1 to 3, wherein Ag as an unavoidable impurity is regulated to 0.05% by mass or less. The method for producing an Al—Mg—Si based alloy plate according to any one of claims 1 to 4, wherein the total content of rare earth elements as unavoidable impurities is regulated to 0.1% by mass or less. The method for producing an Al—Mg—Si based alloy plate according to any one of claims 1 to 5, wherein the heat treatment is carried out after the completion of hot rolling and before the start of cold rolling. The method for producing an Al-Mg-Si-based alloy plate according to any one of claims 1 to 6, wherein the surface temperature of the Al-Mg-Si-based alloy plate immediately after the completion of hot rolling is 200 ° C. or lower. The method for producing an Al—Mg—Si based alloy plate according to any one of claims 1 to 7, wherein the heat treatment temperature is 200 ° C. or higher and 300 ° C. or lower. The method for producing an Al—Mg—Si based alloy plate according to any one of claims 1 to 8, wherein the rolling ratio of cold rolling after heat treatment is 20% or more. The method for producing an Al—Mg—Si based alloy plate according to any one of claims 1 to 9, wherein final annealing is performed after cold rolling. The method for producing an Al—Mg—Si based alloy plate according to claim 10, wherein the final annealing temperature is 200 ° C. or lower. Of the multiple passes of hot rolling, the surface temperature of the Al-Mg-Si alloy plate immediately before the pass is 470 to 350 ° C., and the Al-Mg-Si alloy plate is cooled by the pass, or after the pass and the pass. The method for producing an Al—Mg—Si based alloy plate according to any one of claims 1 to 11, wherein a pass in which the average cooling rate by forced cooling is 50 ° C./min or more is carried out at least once.