EP2570509A1 - Production method for AlMgSi-aluminium strip - Google Patents

Abstract

The method comprises cast rolling bars (1) from an aluminum-magnesium-silicon (AlMgSi) alloy, where during rolling, the rolling bars are subjected to homogenization, are hot-rolled to a hot-rolling temperature and are optionally cold-rolled to a final thickness. The finished rolled tape is solution-annealed and deterred. The hot-rolled strip has, according to the discharge from the last hot-rolling stitch, a temperature of more than 230[deg] C. The hot-rolled strip is deterred using a circuit board radiator and an emulsion-subjected hot-rolling stitch on a discharge temperature. The method comprises cast rolling bars (1) from an aluminum-magnesium-silicon (AlMgSi) alloy, where during rolling, the rolling bars are subjected to homogenization, are hot-rolled to a hot-rolling temperature and are optionally cold-rolled to a final thickness. The finished rolled tape is solution-annealed and deterred. The hot-rolled strip has, according to the discharge from the last hot-rolling stitch, a temperature of more than 230[deg] C. The hot-rolled strip is deterred using a circuit board radiator and an emulsion-subjected hot-rolling stitch on a discharge temperature. The temperature of the hot-rolled strip: before starting the cooling process is more than 400[deg] C; during the last rolling stitch is more than 250[deg] C; and during the last rolling stitch and before recoiling is 200-230[deg] C. A thickness of the finished hot-rolled strip is 5-8 mm. The finished rolled aluminum strip is subjected to heat treatment, with which the aluminum strip is heated to more than 100[deg] C according to solutionizing and deterring and subsequently rolled up and outsourced with a temperature of more than 85[deg] C.

Description

The invention relates to a method for producing a strip of AlMgSi alloy, in which a ingot of an AlMgSi alloy is cast, the ingot is subjected to homogenization, the hot rolled to rolled slab is rolled, then optionally cold rolled to final thickness and finished rolled strip is solution-tempered and quenched. Moreover, the invention relates to advantageous uses of a correspondingly produced AlMgSi aluminum strip.

Above all, in the automotive industry but also in other applications, such as aircraft or rail vehicle sheet metal from aluminum alloys are needed, which are not only characterized by particularly high strength values, but also have a very good forming behavior and allow high degrees of deformation. In automotive engineering typical applications are the body and chassis parts. In the case of visible, painted components, for example exterior body panels, it is necessary that the forming of the materials must be carried out in such a way that the surface after painting is not impaired by defects such as flow patterns or roping. This is particularly important, for example, for the use of aluminum alloy sheets for the production of engine hoods and other body parts of a motor vehicle. However, it restricts the choice of material with regard to the aluminum alloy. In particular AlMgSi alloys, whose main alloying constituents are magnesium and silicon have relatively high strengths in the state T6 with at the same time good forming behavior in the state T4 and excellent corrosion resistance. AlMgSi alloys are the alloy types AA6XXX, for example, the alloy types AA6016, AA6014, AA6181, AA6060 and AA6111. Conventionally, aluminum tapes of AlMgSi alloy are produced by casting a roll bar, homogenizing the roll bar, hot rolling the roll bar, and cold rolling the hot strip. The homogenisation of the rolling ingot takes place at a temperature of 380 to 580 ° C for more than one hour. By a final solution annealing at typical temperatures of 500 ° C to 570 ° C with subsequent quenching and cold aging at about room temperature for at least three days, the tapes can be delivered in condition T4. The state T6 is set after quenching by thermal aging at temperatures between 100 ° C and 220 ° C.

The problem is that coarse Mg ₂ Si precipitates are present in hot-rolled aluminum strips of AlMgSi alloys, which are broken and reduced in the subsequent cold rolling by high degrees of deformation. Hot strips of AlMgSi alloy are usually produced in thicknesses of 3 mm to 12 mm and fed to a cold rolling with high degrees of deformation. Since the temperature range in which the AlMgSi phases form, is traversed very slowly during conventional hot rolling, these phases form very coarse. The temperature range for forming the above-mentioned phases is alloy-dependent. But it lies between 230 ° C and 550 ° C so in the range of hot rolling temperatures. It could be experimentally proven that these coarse phases in the hot strip negatively affect the elongation of the final product. This means that the forming behavior of aluminum strips made of AlMgSi alloys has not yet been fully exploited.

From the published European patent application EP 2 270 249 A1 , which is attributed to the Applicant, it has been proposed that the AlMgSi alloy strip has a maximum temperature of 130 ° C immediately after discharge from the last hot rolling pass and is wound at this or a lower temperature. By quenching the hot strip with this method, it was possible to produce aluminum strips in state T4, which in state T4 has an elongation at break of A80 of more than 30% or an equi-elongation Ag of more than 25%. In addition, very high elongation at break values were found in the T6 state. However, it has been shown that this temperature range at the outlet of the last hot roll pass leads to problems in the flatness of the hot strip, so that the subsequent manufacturing steps were disturbed. In addition, the specified cooling rate could only be achieved with reduced production speeds.
Based on this prior art, the present invention based on the object to provide an improved process for the production of an aluminum strip of an AlMgSi alloy available, with which AlMgSi aluminum strips can be produced with a very good forming behavior in the state T4 process reliable.

According to a first teaching of the present invention, the stated object of a method is achieved in that the hot strip immediately after leaving the last Hot rolling pass a temperature of more than 130 ° C, preferably 135 ° C to a maximum of 250 ° C, preferably 135 ° C to a maximum of 230 ° C and the hot strip is wound at this temperature.

In contrast to the known process with particularly low coiling temperatures showed
Surprisingly, that the mechanical properties in relation to the deformation behavior determining Equal Ag expansion Ag despite the changed
Winding temperatures did not change or only insignificantly changed. The AlMgSi alloy strips produced in accordance with the invention in the condition T4 furthermore showed an equal expansion of more than 25% in the tensile test according to DIN EN. In addition, they showed the very good hardenability in the state T6, as this is known from the applicant's prior application. However, the manufacturing process could be stabilized significantly and a higher production speed could be achieved.

According to an advantageous embodiment of the method according to the invention, this cooling takes place within the last two hot rolling passes, ie the cooling to more than 130 ° C, preferably 135 ° C to 250 ° C, preferably 135 ° C to 230 ° C within seconds, maximum within of five minutes. It has been found that in this procedure, the increased Gleichmaßdehnungswerte at usual strength or Dehngrenzwerte in the state T4 and the improved hardenability in the state T6 are achieved particularly reliable process.

According to a further embodiment of the method according to the invention, a process-reliable cooling of the hot strip is achieved by quenching the hot strip itself to coiling temperature using at least one sinker cooler and the hot rolling passes applied with emulsion. A board cooler consists of an array of coolant or lubricant nozzles which spray a rolling emulsion onto the aluminum strip. The sinker may be present in a hot rolling mill to cool rolled hot strip to rolling temperature prior to hot rolling and to achieve higher production speeds.

If the temperature of the hot strip prior to the start of the cooling process, which takes place preferably within the last two rolling passes, at least 400 ° C, preferably 470 ° C to 490 ° C, is achieved according to a next embodiment of the method that particularly small Mg ₂ Si precipitates are present in the quenched hot strip, since the largest proportion of the alloying constituents magnesium and silicon are present at these temperatures in the dissolved state in the aluminum matrix. This advantageous state of the hot strip is quasi "frozen" by quenching.

According to a further embodiment of the method, the temperature of the hot strip after the penultimate rolling pass is 290 ° C to 310 ° C. It has been found that these temperatures both allow a sufficient freezing of the precipitates and on the other hand at the same time the last pass can be carried out without problems.

If the rolled hot strip at the outlet immediately after the last hot roll pass a temperature of 200 ° C to 230 ° C, an optimum process speed can be achieved during hot rolling without deteriorating the properties of the produced aluminum strip.

The thickness of the finished hot strip is 3 mm to 12 mm, preferably 5 mm to 8 mm, so that conventional cold rolling stands for cold rolling can be used.

Preferably, the aluminum alloy used is of the alloy type AA6xxx, preferably AA6014, AA6016, AA6060, AA6111 or AA6181. All alloy types AA6xxx have in common that they have a particularly good forming behavior characterized by high elongation values in the state T4 and high strength or yield strength in use condition T6, for example, after a hot aging at 205 ° C / 30 min.

According to a further embodiment of the method according to the invention, the finished rolled aluminum strip is subjected to a heat treatment, wherein the aluminum strip is heated after solution treatment and quenching to more than 100 ° C and then at a temperature of more than 55 ° C, preferably more than 85 ° C. wound up and outsourced. This embodiment of the method, after cold aging by a shorter heating phase at lower temperatures, allows to set the state T6 in the strip or sheet in which the sheet-formed or strip-formed components are used in the application. These fast-curing aluminum strips are for this purpose only to temperatures of about 185 ° C for only 20 min. heated to reach the higher yield limits in state T6.

Although the elongation at break values A _{80 of} the aluminum strips produced in this embodiment of the method according to the invention in state T4 are slightly below 29%. However, the aluminum strip produced according to the invention is still characterized by a very good uniform elongation Ag of more than 25% after aging in state T4. Equilibrium Ag is understood as the maximum elongation of the sample at which no constriction of the sample occurs during the tensile test. The sample is thus stretched evenly in the region of the uniform expansion. The value for the uniform elongation used to be a maximum of 22% to 23% for similar materials. The uniform elongation significantly influences the forming behavior, since this determines the maximum degree of deformation of the material used in practice. In this respect, an aluminum strip with very good forming properties can be made available with the method according to the invention, which can also be transferred to the condition T6 via an accelerated thermal aging (185 ° C./20 min.).

An aluminum alloy of the type AA6016 has the following alloy constituents in percent by weight: 0.25% ≤ Mg ≤ 0.6%, 1.0% ≦ Si ≦ 1.5%, Fe ≤ 0.5%, Cu ≤ 0.2%, Mn≤0.2%, Cr ≤ 0.1%, Zn≤0.1%, Ti ≤ 0.1% and residual Al and unavoidable impurities in the sum total of 0.15%, individually a maximum of 0.05%.

At magnesium contents of less than 0.25% by weight, the strength of the aluminum strip intended for structural applications is too low, while on the other hand the workability at magnesium contents deteriorates above 0.6% by weight. Silicon, in interaction with magnesium, is essentially responsible for the hardenability of the aluminum alloy and thus also for the high strength, which can be achieved in the application example after a Lackiereinbrennen. With Si contents of less than 1.0% by weight, the hardenability of the aluminum strip is reduced, so that only reduced strengths can be provided in the application. Si contents of more than 1.5% by weight result in no improvement in the curing behavior of the alloy. The Fe content should be limited to a maximum of 0.5% by weight to prevent coarse precipitation. A limitation of the copper content to a maximum of 0.2 wt .-% leads above all to an improved corrosion resistance of the aluminum alloy in the specific application. The manganese content of less than 0.2% by weight reduces the tendency to form coarser manganese precipitates. Although chromium ensures a fine microstructure, it should be limited to 0.1% by weight in order to avoid coarse precipitation. On the other hand, the presence of manganese improved the weldability by reducing the cracking tendency or the quenching sensitivity of the manganese aluminum strip according to the invention. A reduction of the zinc content to a maximum of 0.1% by weight improves in particular the corrosion resistance of the aluminum alloy or of the finished sheet in the respective application. In contrast, titanium provides grain refining during casting, but should be limited to a maximum of 0.1% by weight to ensure good castability of the aluminum alloy.

An aluminum alloy of the type AA6060 has the following alloy constituents in percent by weight: 0.35% ≤ Mg ≤ 0.6%, 0.3% ≦ Si ≦ 0.6%, 0.1% ≤ Fe ≤ 0.3% Cu ≤ 0.1%, Mn ≤ 0.1%, Cr ≤ 0.05%, Zn≤0.10%, Ti ≤ 0.1% and Residual Al and unavoidable impurities up to a total of 0.15%, individually up to a maximum of 0.05%.

The combination of a precisely predetermined magnesium content with a reduced Si content and narrowly specified Fe content in comparison to the first embodiment results in an aluminum alloy in which the formation of Mg ₂ Si precipitates after hot rolling can be prevented particularly well by the method according to the invention, so that a sheet with improved elongation and high yield strengths can be provided compared to conventionally produced sheets. The lesser Upper limits of the alloying constituents Cu, Mn and Cr additionally reinforce the effect of the process according to the invention. With regard to the effects of the upper limit of Zn and Ti, reference is made to the comments on the first embodiment of the aluminum alloy.

An aluminum alloy of type AA6014 has the following alloy constituents in percent by weight: 0.4% ≤ Mg ≤ 0.8%, 0.3% ≦ Si ≦ 0.6%, Fe ≤ 0.35% Cu ≤ 0.25%, 0.05% ≤ Mn ≤ 0.20%, Cr ≤ 0.20%, Zn≤0.10%, 0.05% ≤ V ≤ 0.20%, Ti ≤ 0.1% and Residual Al and unavoidable impurities up to a total of 0.15%, individually up to a maximum of 0.05%.

An AA6181 aluminum alloy has the following alloy components in weight percent: 0.6% ≤ Mg ≤ 1.0%, 0.8% ≦ Si ≦ 1.2%, Fe ≤ 0.45% Cu ≤ 0.10%, Mn ≤ 0.15%, Cr ≤ 0.10%, Zn≤0.20%, Ti ≤ 0.1% and Residual Al and unavoidable impurities up to a total of 0.15%, individually up to a maximum of 0.05%.

An AA6111 aluminum alloy has the following alloy components in weight percent: 0.5% ≤ Mg ≤ 1.0%, 0.7% ≦ Si ≦ 1.1%, Fe ≤ 0.40% 0.50% ≤ Cu ≤ 0.90%, 0.15% ≤ Mn ≤ 0.45%, Cr ≤ 0.10%, Zn ≤ 0.15%, Ti ≤ 0.1% and Residual Al and unavoidable impurities up to a total of 0.15%, individually up to a maximum of 0.05%. Due to the increased copper content, the AA6111 alloy generally shows higher strength values in the T6 application, but is to be classified as more susceptible to corrosion.

All the aluminum alloys shown are specifically adapted to different applications in their alloy components. As already stated, tapes made of these aluminum alloys, which were produced using the method according to the invention, exhibit particularly high uniform strain values in state T4 coupled with a particularly pronounced increase in the yield strength, for example after heat aging at 205 ° C./30 min. This also applies to the aluminum strips subjected to a heat treatment after solution heat treatment in the condition T4.

Due to the excellent combination of good formability in the state T4, high corrosion resistance and high yield strength Rp0.2 in the operating state (state T6), the above object according to a second teaching of the present invention by the use of an AlMgSi prepared by the process according to the invention Alloy strip for a component, chassis or structural part and sheet in automotive, aircraft or rail vehicle, in particular as a component, chassis part, outer or inner panel in the automotive industry, preferably as a body component solved. Above all, visible body parts, such as hoods, fenders, etc., as well as outer skin parts of a rail vehicle or aircraft benefit from the high yield strengths Rp0.2 with good surface properties even after forming with high degrees of deformation.

Therefore, a fast-setting AlMgSi alloy ribbon having excellent forming properties can be provided by an aluminum alloy ribbon produced according to the present invention, which is subjected to solution annealing followed by heat treatment after its production. In state T4, it has, as already stated, a uniform elongation Ag of more than 25%, for example, at a yield strength Rp0.2 of 80 to 140 MPa. With this variant, a fast-hardening AlMgSi alloy strip, which can also be easily formed at the same time, can be made available. The heat aging to reach the state T6 can be 185 ° C for 20 min., To the required

To achieve stretching limit increases.

According to a next embodiment, an aluminum alloy strip produced according to the invention has an equiaxial elongation Ag of more than 25% in the rolling direction, transverse to the rolling direction and diagonally to the rolling direction, so that a particularly isotropic forming capability is made possible.

The aluminum strips produced according to the invention preferably have a thickness of 0.5 mm to 12 mm. Aluminum strips with thicknesses of 0.5 mm to 2 mm are preferably used for body parts, for example in the automotive industry, while aluminum bands with larger thicknesses of 2 to 4.5 mm, for example, find in chassis parts in automotive applications. Individual components can also be manufactured in a cold-rolled strip with a thickness of up to 6 mm. In addition, in specific applications aluminum strips with thicknesses of up to 12 mm can be used. These very thick aluminum strips are usually provided only by hot rolling.

The invention will now be explained in more detail with reference to embodiments in conjunction with the drawings.

The drawing shows in the only one FIG. 1 a schematic flow diagram of an embodiment of the inventive method for producing a strip of a MgSi aluminum alloy with the steps of a) producing and homogenizing the rolling ingot, b) hot rolling, c) cold rolling and d) solution treatment with quenching.

First, an aluminum alloy ingot 1 having the following alloy components by weight is poured: 0.25% ≤ Mg ≤ 0.6%, 1.0% ≦ Si ≦ 1.5%, Fe ≤ 0.50%, Cu ≤ 0.20%, Mn≤0.20%, Cr ≤ 0.10%, Zn≤0.20%, Ti ≤ 0.15% and Residual Al and unavoidable impurities up to a total of 0.15%, individually up to a maximum of 0.05%.

The ingot produced in this way is homogenized in a furnace 2 for 8 hours at a homogenization temperature of about 550 ° C., so that the alloyed components alloyed in are present in a particularly homogeneous distribution in the rolling ingot. Fig. 1a ).

In 1b ) is shown as the rolling ingot 1 is reversibly hot rolled in the present embodiment of the inventive method by a hot rolling stand 3, wherein the rolling ingot 1 has a temperature of 400 to 550 ° C during hot rolling. In this embodiment, after leaving the hot rolling mill 3 and before the penultimate hot rolling pass, the hot strip 4 preferably has a temperature of at least 400 ° C, preferably 470 ° C to 490 ° C. Preferably, at This hot strip temperature, the quenching of the hot strip 4 using a sinker cooler 5 and the work rolls of the hot rolling stand 3. Preferably, the hot strip is cooled here to a temperature of 290 ° C to 310 ° C before the last hot rolling pass. For this purpose, the sinker 5, sprayed only schematically, the hot strip 4 with cooling rolling emulsion and ensures an accelerated cooling of the hot strip 4 to the last-mentioned temperatures. The work rolls of the hot rolling stand 3 are also subjected to emulsion and cool the hot strip 4 in the last hot roll pass down further. After the last pass, the hot strip 4 at the outlet of the sinker cooler 5 'in the present embodiment has a temperature of 200 ° C to 230 ° C and is then wound on the take-up reel 6 at this temperature.

Characterized in that the hot strip 4 directly at the outlet of the last hot roll pass a temperature of more than 135 ° C to 250 ° C, preferably 200 ° C to 230 ° C or optionally in the last two hot rolling passes using the sinker cooler 5 and the work rolls of the hot rolling stand 3 is brought to said temperatures, the hot strip 4, despite the elevated coiling temperature, has a frozen crystal structure state, which leads to very good uniform elongation properties Ag of more than 25% in the state T4. It can still be processed faster and better due to the higher coiling temperature. The hot strip with a thickness of 3 to 12 mm, preferably 5 to 8 mm is wound on the take-up reel 6. As already stated, the coiling temperature in the present exemplary embodiment is preferably 135 ° C. to 250 ° C.

In the method according to the invention, no or only a few coarse Mg ₂ Si precipitates can now form in the wound hot strip 4. The hot strip 4 has a very favorable for further processing crystal state and can be unwound from the unwinding reel 7, for example, fed to a cold rolling mill 9 and rewound on a take-up reel 8, Fig. 1c ).

The resulting cold-rolled strip 11 is wound up. Subsequently, it is supplied to a solution annealing at temperatures of 520 ° C to 570 ° C and quenching 10, Fig. 1d ). For this purpose, it is again unwound from the coil 12, solution-annealed in an oven 10 and quenched again wound into a coil 13. The aluminum strip can then be delivered after a cold aging at room temperature in the state T4 with maximum formability. Alternatively (not shown), the aluminum strip 11 can be singulated into individual sheets, which are present after a cold aging in the state T4.

In the case of larger aluminum strip thicknesses, for example in chassis applications or components such as brake anchor plates, it is also possible alternatively to carry out piece annealing and then to quench the metal sheets.

In state T6, the aluminum strip or the aluminum sheet is brought by cold aging at 100 ° C to 220 ° C in order to achieve maximum values for the yield strength. For example, a thermal aging can also be performed at 205 ° C / 30 min.

The aluminum strips produced according to the illustrated embodiment, for example, have a thickness of 0.5 to 4.5 mm after cold rolling. Tape thicknesses of 0.5 to 2 mm are commonly used for body applications or tape thicknesses of 2.0 mm to 4.5 mm for chassis parts in the automotive industry. In both applications, the improved uniform strain values in the manufacture of the components are of crucial advantage, since mostly strong deformations of the sheets are carried out and still high strengths in the operating condition (T6) of the end product are required.

Table 1 shows the alloy compositions of aluminum alloys from which aluminum tapes have been produced conventionally or according to the invention. In addition to the contents of alloying constituents shown, the aluminum strips contain aluminum and impurities as a residual proportion, individually not more than 0.05% by weight and in total not more than 0.15% by weight. Table 1 bands Si% by weight Fe% by weight Cu% by weight Mn% by weight Mg% by weight Cr% by weight Zn% by weight Ti weight% 251 1.3 0.19 - 0.06 0, 3 - 0.01 0.02 252 1.3 0.19 - 0.06 0.3 - 0.01 0.02 491-1 1.39 0.18 0,002 0, 062 0.30 0.0006 0.01 0.0158 491-11 1.40 0.18 0, 002 0.063 0.31 0.0006 0.0104 0.0147

The tapes (samples) 251 and 252 were made by a process according to the invention, in which the hot strip was heated to about 135 ° C to 250 ° C within the last two hot rolling passes from about 470 ° C to 490 ° C Board cooler and the hot rolling itself cooled and wound up. Table 2 shows the measured values of these bands as "Inv." characterized. This was followed by cold rolling to a final thickness of 0.865 mm.

The tapes (samples) 491-1 and 491-11 were made with conventional hot rolling and cold rolling and with a "conv." characterized.

The results of the mechanical properties shown in Table 2 clearly show the difference in the achievable uniform strain values Ag. Table 2 Bander T4 T6 205 ° C / 30 min. Thickness (mm) Rp0.2 (MPa) R _m (MPa) A _g (%) A ₈₀ (%) Rp0.2 (MPa) R _m (MPa) A _g (%) ΔRp0.2 (MPa) 251 l Inv. 0, 865 93 207 26.3 30.4 251 Q. Inv. 0.865 86 203 26.4 29.0 193 249 12, 4 107 251 D Inv. 0, 865 87 203 27.0 30.0 252 l Inv. 0.865 93 206 26.1 31.5 252 p Inv. 0.865 88 205 26.6 29.0 185 244 12.2 97 252 D Inv. 0.865 87 202 27.3 31.1 491-1 Conv. 1.04 92 202 23.1 27.8 180 235 10.7 88 491-11 Conv. 1.04 88 196 23.0 27.4 179 232 11.2 91

To obtain the T4 state, the strips were subjected to solution annealing with subsequent quenching and subsequent cold aging for eight days at room temperature. The T6 state was achieved by cold aging followed by aging at 205 ° C for 30 minutes.

The samples marked L were cut in the rolling direction, the samples marked Q were cut transversely to the rolling direction, and the samples denoted D were cut diagonally to the rolling direction. The samples 491-1 and 491-11 were each measured transversely to the rolling direction.

It was found that the advantageous microstructure, which was set in the bands 251 and 252 by means of the method according to the invention, permits a significant increase in the uniform elongation Ag with identical yield strength Rp0.2 and strength Rm. The uniform elongation Ag increased from 23.0% to a maximum of 26.6% across the rolling direction in the According to the invention produced bands compared to the conventionally produced tapes.

The microstructure set with the method according to the invention leads to the particularly advantageous combination of high uniform elongation Ag of more than 25% at very high values for the yield strength Rp0.2 of 80 to 140 MPa. In state T6, the yield strength Rp0.2 increases to at least 185 MPa, with the uniform elongation Ag still remaining at more than 12%. The curability with a ΔRp0.2 of 97 and 107 MPa is still very good in the tapes produced according to the invention.

In state T6, the increase in the uniform elongation Ag was virtually preserved compared to conventionally produced strips.

The elongation at break values Ag and A ₈₀ , the elongation limits Rp0,2 and the tensile strength values Rm in the tables were measured according to DIN EN.

Claims (9)

A method of making a strip of AlMgSi alloy, casting a billet of AlMgSi alloy, homogenizing the billet, hot rolling the billet to hot rolling temperature, then optionally cold rolling to final gauge and solution tempering and quenching the finish rolled strip becomes,
characterized in that the hot strip immediately after the discharge from the last hot roll pass a temperature of more than 130 ° C to 250 ° C, preferably up to 230 ° C and the hot strip is wound at this temperature. Method according to claim 1,
characterized in that the hot strip is quenched itself to the outlet temperature using at least one sinker cooler and the emulsion-loaded hot rolling passes. Method according to claim 1 or 2,
characterized in that the temperature of the hot strip prior to the start of the cooling process during hot rolling is more than 400 ° C. Method according to one of claims 1 to 3,
characterized in that the temperature of the hot strip after the penultimate Walzstich is more than 250 ° C. Method according to one of claims 1 to 4,
characterized in that the temperature of the hot strip after the last rolling pass before the coiling is 200 ° C to 230 ° C. Method according to one of claims 1 to 5,
characterized in that the thickness of the finished hot strip is 3 mm to 12 mm, preferably 5 mm to 8 mm. Method according to one of claims 1 to 6,
characterized in that the aluminum alloy is of the alloy type AA6xxx, preferably AA6014, AA6016, AA6060, AA6111 or AA6181. Method according to one of claims 1 to 7,
characterized in that the finished rolled aluminum strip is subjected to a heat treatment in which the aluminum strip after solution annealing and quenching is heated to more than 100 ° C and then wound at a temperature of more than 55 ° C, preferably more than 85 ° C and paged becomes. Use of an aluminum strip produced by a method according to one of claims 1 to 8 for a component, suspension or structural part or sheet metal in motor vehicle, aircraft or rail vehicle construction, in particular as a component, chassis part, exterior or Inner panel in the automotive industry, preferably as a body component.

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