Aluminium alloy products having high electrical and thermal conductivity and improved mechanical properties, and manufacturing method

Abstract

In the method according to the invention, an aluminium alloy is prepared having a composition of, in wt.%, Si: 0.4-1.4, Fe: up to 0.5, Cu: up to 0.8, Mg: 0.2-0.9; Mn: 0.08-0.8 and / or Cr: 0.06-0.5, Zn: up to 0.5, where Mn + Cr + Zn ≥ 0.10; Ti: up to 0.05, V: up to 0.05, other elements or impurities < 0.05 each and < 0.15 total, the remainder being aluminium, which aluminium alloy is cast, homogenised, hot-rolled and optionally cold-rolled and heat-treated, the final thickness of the metal sheet being 0.5 mm to 10 mm, the transformation conditions being determined so as to obtain an IACS conductivity of at least 47% and to obtain, in the long-transverse direction, either a yield strength Rp0.2 of at least 35 MPa and an elongation A % of at least 25%, or a yield strength Rp0.2 of at least 145 MPa and an elongation A % of at least 5%. The products obtained by the method according to the invention are particularly advantageous for applications requiring good electrical or thermal conductivity such as heat sinks, battery cooling channels, stamped cooling panels, conductive bars, flat-panel cooling plates, chilled plates, squirrel-cage rotors, and roofing coils.

Description

[0001] DESCRIPTION

[0002] TITLE: Aluminum alloy products with high electrical and thermal conductivity and improved mechanical properties and manufacturing process

[0003] FIELD OF INVENTION

[0004] The invention relates to aluminium alloy products with high electrical and thermal conductivities and improved mechanical properties, as well as their manufacturing process.

[0005] STATE OF THE ART

[0006] For many aluminum alloy products, electrical and thermal conductivity properties are important. It is known that the electrical and thermal conductivities of metals are correlated according to the Wiedemann-Franz law. In the following description, we will refer to electrical conductivity; however, the results are correlated for thermal conductivity.

[0007] Examples include heat sink applications such as structural parts that dissipate heat, for example computer cases, satellite receivers, battery cooling applications such as battery cooling channels, stamped cooling panels, conductive bars such as bus bars, flat screen cooling plates, fiat panel cooling plates, squirrel cage rotors used especially in induction motors, and roof coils.

[0008] In general, age-hardening alloys have lower electrical or thermal resistivity than 1xxx or 3xxx series alloys because structurally hardening alloys contain significantly more solutes and obstacles in the form of precipitates, which impact electrical and thermal conductivity. The advantage of structurally hardening alloys is that they are generally stronger, potentially allowing the use of thinner products. However, there is a bias against their use in applications requiring high electrical conductivity.

[0009] US20020174923 A1 relates to a process for manufacturing an Al-Mg-Si series alloy plate with improved thermal conductivity and hardness. WO2017 / 168891 relates to a process for manufacturing an Al-Mg-Si alloy plate with improved thermal conductivity, electrical conductivity, and mechanical strength, with a hot rolling exit temperature of 230 °C or less.

[0010] US20190127826 aims to supply an aluminum alloy sheet that can serve as a substitute for an iron- or copper-based metallic material and that has high strength, as well as a conductive element, a battery element, a fastening element, a spring element and a structural element comprising the aluminum alloy material.

[0011] JP2006257505 relates to an aluminum alloy sheet comprising, by weight, 0.1 to 2.5% Si and 0.1 to 3.0% Mg, the remainder being composed of Al and impurities. In the aluminum alloy sheet, the average crystalline grain size in the thickness direction is controlled to <20 µm, the average electrical conductivity is controlled to 45 to 65% IACS, and the Vickers hardness is controlled to 40 to 65 Hv.

[0012] JP2020033604 relates to a method for manufacturing an Al-Mg-Si alloy sheet with a thickness between 0.2 mm and 3 mm, comprising sequential hot rolling and cold rolling of a cast ingot containing Si: 0.2 to 0.8 wt%, Mg: 0.3 to 1 wt%, Fe: 0.5 wt% or less, and Cu: 0.5 wt% or less, and further containing at least one type of Ti: 0.1 wt% or less or B: 0.1 wt% or less, and the remainder being Al with unavoidable impurities. In this method, the surface temperature of the Al-Mg-Si alloy sheet immediately after hot rolling is 230 °C or less.

[0013] CN110872664 relates to an Al-Mg-Si alloy sheet, and more particularly to an Al-Mg-Si alloy sheet exhibiting improved thermal conductivity, electrical conductivity and excellent mechanical strength.

[0014] JP2020033608 relates to a method for manufacturing an Al-Mg-Si based alloy sheet having high conductivity and resistance.

[0015] JP4807484 relates to an aluminum, magnesium and silicon (Al-Mg-Si) alloy sheet, intended for forming operations, particularly for automotive body applications, said sheet having excellent bending properties and the method of manufacturing said sheet.

[0016] JP2005082827 aims to provide an Al-Mg-Si based aluminum alloy sheet for forming, exhibiting excellent bendability and high performance stability, particularly when used as automotive body sheet or equivalent. JP2006037139 relates to a 6000 series aluminum alloy sheet for superplastic forming, exhibiting excellent hardenability, and in which the formation of coarse abnormal grains is avoided even after superplastic forming. The invention also relates to a method for manufacturing said sheet

[0017] Today, there is a need for industrially feasible methods for manufacturing aluminum alloy products that offer a good compromise between high electrical and thermal conductivity and improved mechanical properties.

[0018] SUBJECT OF THE INVENTION

[0019] A first object of the invention is a process for manufacturing an aluminum alloy sheet in which a) an aluminum alloy is prepared with the following composition, in wt%: Si: 0.4 - 1.4, Fe: up to 0.5, Cu: up to 0.8, Mn: 0.08 - 0.8 and / or Cr: 0.06 - 0.5, with Mn + Cr + Zn > 0.10, Mg: 0.2 - 0.9, Zn: up to 0.5, Ti: up to 0.05, V: up to 0.05, other elements or impurities < 0.05 each and < 0.15 total, remainder aluminum, b) it is cast in the form of a rolling sheet by vertical semi-continuous casting, c) said rolling sheet is homogenized at a temperature of 400 to 600 °C for a duration of 1 at 24 hours, d) the said homogenized plate is hot-rolled to a final exit temperature greater than or equal to 230 °C, e) optionally the said cast, homogenized and hot-rolled sheet is cold-rolled with a reduction of up to 95% and a final heat treatment is carried out on the said cast, homogenized sheet,hot-rolled and cold-rolled at a temperature of 150 to 400 °C and for a duration of 1 to 24 hours, characterized in that the final thickness of the sheet is from 0.5 mm to 10 mm and in that the processing conditions are determined so as to obtain at the end of step d or step e if it is carried out an IACS conductivity of at least 47% and to obtain in the cross-length direction either a yield strength Rp0.2 of at least 35 MPa and an elongation A% of at least 25%, or a yield strength Rp0.2 of at least 145 MPa and an elongation A% of at least 5%.

[0020] A second object of the invention is an aluminum alloy sheet with a thickness of 0.5 to 10 mm, composed, by weight percentage, of: Si: 0.4 - 1.4, Fe: up to 0.5, Cu: up to 0.8, Mn: 0.08 - 0.8 and / or Cr: 0.06 - 0.5, with Mn + Cr + Zn > 0.10, Mg: 0.2 - 0.9, Zn: up to 0.5, Ti: up to 0.05, V: up to 0.05, other elements or impurities < 0.05 each and < 0.15 total, remainder aluminum, obtainable by the process according to the first object and having an electrical conductivity (IACS) of at least 47% and, in the long transverse direction, a yield strength (Rp0.2) of at least 35 MPa and an elongation (A%). of at least 25%.

[0021] A third object of the invention is an aluminum alloy sheet with a thickness of 0.5 to 10 mm, composed, by weight percentage, of: Si: 0.4 - 1.4, Fe: up to 0.5, Cu: up to 0.8, Mn: 0.08 - 0.8 and / or Cr: 0.06 - 0.5, with Mn + Cr + Zn > 0.10, Mg: 0.2 - 0.9, Zn: up to 0.5, Ti: up to 0.05, V: up to 0.05, other elements or impurities < 0.05 each and < 0.15 total, remainder aluminum, obtainable by the process according to the first object and having an electrical conductivity (IACS) of at least 47% and, in the long transverse direction, a yield strength (Rp0.2) of at least 145 MPa and an elongation (A) % of at least 5%.

[0022] A fourth object of the invention is the use of aluminum alloy sheet obtained according to the process of the invention, with a thickness of 0.5 to 10 mm and a composition, in % by weight: Si: 0.4 - 1.4, Fe: up to 0.5, Cu: up to 0.8, Mg: 0.2 - 0.9, Mn: 0.08 - 0.8, Zn: up to 0.5, Ti: up to 0.05, V: up to 0.05, other elements or impurities < 0.05 each and < 0.15 total, remainder aluminum, having an electrical conductivity (IACS) of at least 47% and, in the long transverse direction, a yield strength (Rp0.2) of at least 35 MPa and an elongation (A%) of at least 25% for applications such as heat sinks, battery cooling channels, and cooling panels. stamped.

[0023] A fifth object of the invention is the use of aluminum alloy sheet obtained according to the process of the invention, with a thickness of 0.5 to 10 mm and a composition, in % by weight: Si: 0.4 - 1.4, Fe: up to 0.5, Cu: up to 0.8, Mg: 0.2 - 0.9, Mn: 0.08 - 0.8, Zn: up to 0.5, Ti: up to 0.05, V: up to 0.05, other elements or impurities < 0.05 each and < 0.15 total, remainder aluminum, having an electrical conductivity (IACS) of at least 47% and, in the long transverse direction, a yield strength (Rp0.2) of at least 145 MPa and an elongation (A%) of at least 5% for applications such as conductive bars, flat panel cooling plates, and other plates. refrigerated, squirrel cage rotors used especially in induction motors, roof coils.

[0024] DETAILED DESCRIPTION OF THE INVENTION

[0025] The designation of alloys is in accordance with the regulations of the Aluminium Association (AA), which are familiar to those skilled in the art. In particular, the 6XXX series is defined in these regulations. The definitions of the metallurgical states are given in the European standard EN 515. Unless otherwise specified, the definitions of standard EN 12258-1 apply. Unless otherwise stated, compositions are given as percentages by weight. A formula such as Mn + Cr + Zn > 0.10 means that the sum of the contents of Mn, Cr, and Zn, expressed as percentages by weight, is greater than or equal to 0.10.

[0026] Unless otherwise specified, the static mechanical properties, in other words the tensile strength Rm, the tensile yield strength Rp0.2, and the elongation at break A%, are determined by a tensile test according to EN 10002-1 or NF EN ISO 6892-1. The location and orientation of the parts are defined by EN 485-1. Unless otherwise specified, the mechanical properties are measured in the long transverse (LT) direction.

[0027] The electrical conductivity % IACS, percentage of the IACS (International Annealed Copper Standard) conductivity, was determined. 100% IACS is equivalent to a conductivity of 58 x 10⁸ megasiemens per meter (MS / m) at 20 °C or a resistivity of 1 / 58 x 10⁸ ohm per meter for a wire with a cross-section of one square millimeter.

[0028] The proposed solution improves the trade-off between mechanical property and electrical conductivity by increasing hardness with negligible changes in electrical conductivity.

[0029] The proposed solution to the problem uses a selection of 6XXX series alloy and optimized process steps to improve the trade-off between mechanical property and electrical conductivity by increasing hardness with negligible changes in electrical conductivity.

[0030] The inventors have surprisingly found that by acting on the transformation conditions, it is possible to obtain with certain 6XXX alloys high electrical and thermal conductivity and improved mechanical properties (Rp0.2, %A) compared to prior art alloys such as 3003 and 1050 alloys. Furthermore, these 6XXX alloy products are obtained economically through a process in which separate solution treatment and quenching steps are not required, thanks to the hot rolling conditions defined in the process according to the invention, which makes it possible to obtain the desired effects on the sheet even in the absence of solution treatment and quenching.

[0031] Thus, according to the invention, such products are manufactured by a process in which a) an aluminum alloy is prepared with the following composition, in % by weight: Si: 0.4 - 1.4, Fe: up to 0.5, Cu: up to 0.8, Mg: 0.2 - 0.9, Mn: 0.08 - 0.8 and / or Cr: 0.06 - 0.5, Mn + Cr + Zn > 0.10, Zn: up to 0.5, Ti: up to 0.05, V: up to 0.05, other elements or impurities < 0.05 each and < 0.15 total, remainder aluminum, b) it is cast in the form of a rolling plate by vertical semi-continuous casting, c) said rolling plate is homogenized at a temperature of 400 to 600 °C for a period of 1 to 24 hours, d) the homogenized plate is hot-rolled to a final exit temperature of 230 °C or higher, e) optionally the cast, homogenized and hot-rolled plate is cold-rolled to a reduction of up to 95% and a final heat treatment is carried out on the cast, homogenized plate,hot-rolled and cold-rolled at a temperature of 150 to 400 °C and for a duration of 1 to 24 hours, characterized in that the final thickness of the sheet is from 0.5 mm to 10 mm and in that the processing conditions are determined so as to obtain at the end of step d or step e if it is carried out an IACS conductivity of at least 47% and to obtain in the cross-length direction either a yield strength Rp0.2 of at least 35 MPa and an elongation A% of at least 25%, or a yield strength Rp0.2 of at least 145 MPa and an elongation A% of at least 5%.

[0032] Among the transformation steps determined so as to obtain at the end of step d or step e if it is carried out, the desired properties, the cold rolling conditions, including the cold rolling ratio, and the conditions of the final heat treatment can in particular be determined as illustrated by the examples.

[0033] The sum of the Zn, Mn, and Cr contents is greater than or equal to 0.10. The addition of Mn, Cr, or Zn negatively impacts conductivity but contributes to the hardening of the alloy. According to the invention, with a sum of the contents of these elements greater than or equal to 0.10, the mechanical strength is improved without significantly affecting the conductivity. Even if an element among Zn, Mn, and Cr was not selected for addition, its contribution to the sum of the contents of these elements is taken into account.

[0034] The Cr content is 0.06% to 0.5% and / or the Mn content is 0.08% to 0.8%. If Cr is not selected, its content is at most 0.05%, and preferably at most 0.04%. If Mn is not selected, its content is at most 0.07%, and preferably at most 0.06%, and even more preferably at most 0.05%. Preferably, the sum of the Mn and Cr contents is greater than or equal to 0.10. An advantageous embodiment in which the sum of the Mn and Cr contents is greater than or equal to 0.10 necessarily implies the condition Mn + Cr + Zn > 0.10, which need not be stated again in this embodiment. Thus, an embodiment according to the invention is a process in which a) an aluminum alloy is prepared with the following composition, in % by weight: Si: 0.4 - 1.4, Fe: up to 0.5, Cu: up to 0.8, Mg: 0.2 - 0.9, Mn: 0.08 - 0.8 and / or Cr: 0.06 - 0.5, Mn + Cr > 0.10, Zn: up to 0.5, Ti: up to 0.05, V: up to 0.05, other elements or impurities < 0,0.5 each and < 0.15 total, remaining aluminum, b) it is cast in the form of a rolling plate by vertical semi-continuous casting, c) said rolling plate is homogenized at a temperature of 400 to 600 °C for a period of 1 to 24 hours, d) said homogenized plate is hot-rolled at a final exit temperature greater than or equal to 230 °C, e) optionally said hot-rolled, homogenized cast sheet is cold-rolled with a reduction of up to 95% and a final heat treatment of said hot-rolled, homogenized cast sheet is carried out at a temperature of 150 to 400 °C for a period of 1 to 24 hours, characterized in that the final thickness of the sheet is 0,5 mm to 10 mm and in that the transformation conditions are determined so as to obtain at the end of step d or step e if it is carried out an IACS conductivity of at least 47% and to obtain in the transverse-long direction either a yield strength Rp0.2 of at least 35 MPa and an elongation A% of at least 25%, or a yield strength Rp0.2 of at least 145 MPa and an elongation A% of at least 5%.

[0035] In an advantageous embodiment, the chromium (Cr) content is 0.07% to 0.25% and the manganese (Mn) content is at most 0.05%. In another advantageous embodiment, the manganese (Mn) content is 0.08% to 0.50% and the chromium (Cr) content is at most 0.05%. The inventors have found that, surprisingly, it is possible to add manganese (Mn) and optionally chromium (Cr) without adversely affecting conductivity using the applied process. The addition of manganese (Mn) and / or chromium (Cr) contributes to the hardening of the alloy, particularly by controlling grain formation and recrystallization, without degrading elongation, thanks to the applied process.

[0036] It is possible to optionally add up to 0.5% zinc. As with manganese and chromium, adding up to 0.5% zinc also has a detrimental effect on conductivity but contributes to the hardening of the alloy. In one embodiment, the zinc content is 0.06% to 0.4%, and preferably 0.10% to 0.3%. If zinc is not selected, its content is at most 0.04%, and preferably at most 0.03%. The compositions of the invention mention other elements or impurities < 0.05%, meaning that the elements present in the indicated range may have been added intentionally or are present as impurities.

[0037] The alloy composition is advantageously chosen from the alloys defined by the intersection of the composition according to the invention and the composition defined by the Aluminium Association under one of the references AA6061, AA6082, AA6005, AA6005A, AA611, AA6316, AA6216, AA6016, preferably AA6061, AA6082, AA6005, AA6005A and AA6111.

[0038] The composition defined by the Aluminium Association under reference AA6005A is, in % by weight, as follows: Si: 0.50 - 0.9, Fe: up to 0.35, Cu: up to 0.30, Mg: 0.40 - 0.7, Mn: up to 0.50, Cr: up to 0.30, with Mn+Cr: 0.12-0.50, Zn: up to 0.20, Ti: up to 0.10, V: up to 0.05, other elements up to 0.05 each and up to 0.15 total, remainder aluminium.

[0039] The composition of the alloy defined by the intersection of the composition according to the invention and the composition defined by the Aluminium Association under reference AA6005A is therefore, in % by weight, as follows: Si: 0.50 - 0.9, Fe: up to 0.35, Cu: up to 0.30, Mg: 0.40 - 0.7, Mn: 0.08 - 0.50 and / or Cr: 0.06 - 0.30, with Mn+Cr: 0.12-0.50, Zn: up to 0.20, Ti: up to 0.05, V: up to 0.05, other elements or impurities < 0.05 each and < 0.15 total, remainder aluminium.

[0040] The composition defined by the Aluminium Association under reference AA6111 is, in % by weight, as follows: Si: 0.6 - 1.1, Fe: up to 0.40, Cu: 0.50 - 0.9, Mg: 0.50 - 1.0, Mn: 0.10 - 0.45, Cr: up to 0.10, Zn: up to 0.15, Ti: up to 0.10, V: up to 0.05, other elements or impurities up to 0.05 each and up to 0.15 total, remainder aluminium.

[0041] The composition of the alloy defined by the intersection of the composition according to the invention and the composition defined by the Aluminium Association under reference AA6111 is therefore, in % by weight, as follows: Si: 0.6 - 1.1, Fe: up to 0.40, Cu: 0.50 - 0.8, Mg: 0.50 - 0.9, Mn: 0.10 - 0.45, optionally Cr: 0.06 - 0.10, Zn: up to 0.15, Ti: up to 0.05, V: up to 0.05, other elements or impurities < 0.05 each and < 0.15 total, remainder aluminium.

[0042] The composition defined by the Aluminium Association under reference AA6082 is, in % by weight, as follows: Si: 0.7 - 1.3, Fe: up to 0.50, Cu: up to 0.10, Mg: 0.6 - 1.2, Mn: 0.40 - 1, Cr: up to 0.25, Zn: up to 0.20, Ti: up to 0.10, V: up to 0.05, other elements or impurities up to 0.05 each and up to 0.15 total, remainder aluminium.

[0043] The composition of the alloy defined by the intersection of the composition according to the invention and the composition defined by the Aluminium Association under reference AA6082: is, in % by weight, as follows: Si: 0.7 - 1.3, Fe: up to 0.50, Cu: up to 0.10, Mg: 0.6 - 0.9, Mn: 0.40 - 0.8 optionally Cr: 0.06 - 0.25, Zn: up to 0.20, Ti: up to 0.05, V: up to 0.05, other elements or impurities < 0.05 each and < 0.15 total, remainder aluminium.

[0044] The composition defined by the Aluminium Association under reference AA6061 is, in % by weight, as follows: Si: 0.40 - 0.8, Fe: up to 0.7, Cu: 0.15 - 0.40, Mg: 0.8 - 1.2, Mn: up to 0.15, Cr: 0.04 - 0.35, Zn: up to 0.25, Ti: up to 0.15, V: up to 0.05, other elements or impurities up to 0.05 each and up to 0.15 total, remainder aluminium.

[0045] The composition of the alloy defined by the intersection of the composition according to the invention and the composition defined by the Aluminium Association under reference AA6061: is, in % by weight, as follows: Si: 0.40 - 0.8, Fe: up to 0.5, Cu: 0.15 - 0.40, Mg: 0.8 - 0.9, Mn: 0.08 - 0.15 and / or Cr: 0.06 - 0.35 with Mn + Cr + Zn > 0.10, Zn: up to 0.25, Ti: up to 0.05, V: up to 0.05, other elements or impurities < 0.05 each and < 0.15 total, remainder aluminium.

[0046] After preparation, the alloy is cast by vertical semi-continuous casting ("DC casting") to obtain a rolling slab. The rolling slab is homogenized at a temperature of 400 to 600 °C for a period of 1 to 24 hours, and preferably at a temperature of 500 to 580 °C for a period of 4 to 23 hours.

[0047] The homogenized rolling plate is then hot-rolled with an outlet temperature greater than or equal to 230 °C.

[0048] Advantageously, the hot rolling outlet temperature is above 250 °C, preferably above 270 °C.

[0049] After hot rolling, the sheet metal typically has a thickness of 3 mm to 11 mm.

[0050] Optionally, the said cast, homogenized and hot-rolled sheet is cold-rolled with a reduction of up to 95% and a final heat treatment is carried out on the said cast, homogenized, hot-rolled and cold-rolled sheet at a temperature of 150 to 400 °C and for a period of 1 to 24 hours.

[0051] The final thickness of the sheet metal, after hot rolling and optionally cold rolling, is 0.5 to 10 mm. Preferably, the final thickness of the sheet metal is 0.75 to 8 mm, preferably 1.0 to 3.0 mm.

[0052] In the embodiment where cold rolling and final heat treatment are performed, the reduction ratio is advantageously at least 40% and / or the duration of the final heat treatment is from 1 to 20 hours, preferably from 1 to 16 hours. In one embodiment of the process, the final heat treatment of said cast, homogenized, hot-rolled, and cold-rolled sheet is carried out at a temperature of 250 to 400 °C and for a duration of 1 to 24 hours.

[0053] In a first embodiment, the transformation conditions are determined so as to obtain, at the end of the hot rolling or cold rolling and final heat treatment step, if these optional steps are carried out, an IACS conductivity of at least 47% and to obtain in the cross-long direction a yield strength Rp0.2 of at least 35 MPa and an elongation A% of at least 25%.

[0054] In this first embodiment, the final heat treatment temperature when carried out is preferably 250 to 400 °C, advantageously 275 to 400 °C, and preferably 300 to 400 °C.

[0055] In this first embodiment, the duration of the final heat treatment is preferably from 1 to 20 hours, preferably from 1 to 10 hours, more preferably from 2 to 8 hours.

[0056] In a second embodiment of the process, the transformation conditions are determined so as to obtain, after the hot rolling or cold rolling and final heat treatment step (if these optional steps are performed), an IACS conductivity of at least 47% and a yield strength Rp0.2 of at least 145 MPa and an elongation A% of at least 5% in the cross-length direction. In this second embodiment, the final heat treatment, when performed, is preferably carried out at a temperature of 150 to 325 °C for a duration of 1 to 24 hours.

[0057] The aluminum alloy sheet obtainable according to the first embodiment of the process according to the invention has a thickness of 0.5 to 10 mm and a composition, in % by weight: Si: 0.4 - 1.4, Fe: up to 0.5, Cu: up to 0.8, Mg: 0.2 - 0.9, Mn: 0.08 - 0.8 and / or Cr: 0.06 - 0.5, with Mn + Cr + Zn > 0.10, Zn: up to 0.5, Ti: up to 0.05, V: up to 0.05, other elements or impurities < 0.05 each and < 0.15 total, remaining aluminum, and exhibits an electrical conductivity (IACS) of at least 47% and, in the long transverse direction, a yield strength (Rp0.2) of at least 35 MPa and an elongation (A%). of at least 25%.

[0058] In one embodiment, the aluminum alloy sheet obtainable according to the first embodiment of the process according to the invention has a thickness of 0.5 to 10 mm and a composition, in % by weight: Si: 0.4 - 1.4, Fe: up to 0.5, Cu: up to 0.8, Mg: 0.2 - 0.9, Mn: 0.08 - 0.8 and / or Cr: 0.06 - 0.5, with Mn + Cr > 0.10, Zn: up to 0.5, Ti: up to 0.05, V: up to 0.05, other elements or impurities < 0.05 each and < 0.15 total, remaining aluminum, and exhibits an electrical conductivity (IACS) of at least 47% and, in the long transverse direction, a yield strength (Rp0.2) of at least 35 MPa and an elongation A% of at least 25%.

[0059] The use of such aluminum alloy sheet for applications such as heat sinks, battery cooling channels, and stamped cooling panels is advantageous.

[0060] The aluminum alloy sheet obtainable according to the second embodiment of the process according to the invention has a thickness of 0.5 to 10 mm and a composition, in % by weight: Si: 0.4 - 1.4, Fe: up to 0.5, Cu: up to 0.8, Mg: 0.2 - 0.9, Mn: 0.08 - 0.8 and / or Cr: 0.06 - 0.5, with Mn + Cr + Zn > 0.10, Zn: up to 0.5, Ti: up to 0.05, V: up to 0.05, other elements or impurities < 0.05 each and < 0.15 total, remaining aluminum, and exhibits an electrical conductivity (IACS) of at least 47%, a yield strength (Rp0.2) of at least 145 MPa, and an elongation (A%) of at least 5 %.

[0061] In one embodiment, the aluminum alloy sheet obtainable according to the second embodiment of the process according to the invention has a thickness of 0.5 to 10 mm and a composition, in % by weight: Si: 0.4 - 1.4, Fe: up to 0.5, Cu: up to 0.8, Mg: 0.2 - 0.9, Mn: 0.08 - 0.8 and / or Cr: 0.06 - 0.5, with Mn + Cr > 0.10, Zn: up to 0.5, Ti: up to 0.05, V: up to 0.05, other elements or impurities < 0.05 each and < 0.15 total, remaining aluminum, and exhibits an electrical conductivity (IACS) of at least 47%, a yield strength (Rp0.2) of at least 145 MPa, and an elongation (A%) of minus 5%.

[0062] The use of such aluminum alloy sheet for applications such as conductor bars, flat screen cooling plates, refrigerated plates, squirrel cage rotors used especially in induction motors, and roof coils is advantageous.

[0063] In an embodiment in which the composition is at the intersection of the composition of the alloy according to the invention and the AA6061 alloy, the sheet according to the invention has an electrical conductivity IACS of at least 48% and, in the long cross direction, a yield strength Rp0.2 of at least 40 MPa and preferably at least 55 MPa and an elongation A% of at least 25% and preferably at least 30% or a yield strength Rp0.2 of at least 150 MPa and preferably at least 190 MPa and an elongation A% of at least 5% and preferably at least 15%.The composition of the alloy defined by the intersection of the composition according to the invention and the composition defined by the Aluminium Association under reference AA6061: is, in % by weight, as follows: Si: 0.40 - 0.8, Fe: up to 0.5, Cu: 0.15 - 0.40, Mg: 0.8 - 0.9, Mn: 0.08 - 0.15 and / or Cr: 0.06 - 0.35, with Mn + Cr + Zn > 0.10, Zn: up to 0.25, Ti: up to 0.05, V: up to 0.05, other elements or impurities < 0.05 each and < 0.15 total, remainder aluminium.

[0064] In an embodiment in which the composition is at the intersection of the composition of the alloy according to the invention and the AA6082 alloy, the sheet according to the invention has an electrical conductivity IACS of at least 53% and, in the long cross direction, a yield strength Rp0.2 of at least 40 MPa and preferably at least 80 MPa and an elongation A% of at least 25% and preferably at least 30% or a yield strength Rp0.2 of at least 150 MPa and preferably at least 180 MPa and an elongation A% of at least 8% and preferably at least 14%.The composition of the alloy defined by the intersection of the composition according to the invention and the composition defined by the Aluminium Association under reference AA6082: is, in % by weight, as follows: Si: 0.7 - 1.3, Fe: up to 0.50, Cu: up to 0.10, Mg: 0.6 - 0.9, Mn: 0.40 - 0.8, optionally Cr: 0.06 - 0.25, Zn: up to 0.20, Ti: up to 0.05, V: up to 0.05, other elements or impurities < 0.05 each and < 0.15 total, remainder aluminium.

[0065] In an embodiment in which the composition is at the intersection of the composition of the alloy according to the invention and the AA6005A alloy, the sheet according to the invention has an electrical conductivity IACS of at least 53% and, in the long cross direction, a yield strength Rp0.2 of at least 36 MPa and preferably at least 38 MPa and an elongation A% of at least 29% and preferably at least 30%. The composition of the alloy defined by the intersection of the composition according to the invention and the composition defined by the Aluminium Association under reference AA6005A: is, in % by weight, as follows: Si: 0.50 - 0.9, Fe: up to 0.35, Cu: up to 0.30, Mg: 0.40 - 0.7, Mn: 0.08 - 0.50 and / or Cr: 0.06 - 0.30, with Mn + Cr: 0.12 - 0.50, Zn: up to 0.20, Ti: up to 0.05, V: up to 0.05, other elements or impurities < 0.05 each and < 0.15 total, remainder aluminium.

[0066] In an embodiment in which the composition is at the intersection of the composition of the alloy according to the invention and the AA6111 alloy, the sheet according to the invention has an electrical conductivity IACS of at least 51% and, in the long cross direction, a yield strength Rp0.2 of at least 140 MPa and preferably at least 190 MPa and an elongation A% of at least 9% and preferably at least 12%. The composition of the alloy defined by the intersection of the composition according to the invention and the composition defined by the Aluminium Association under reference AA6111: is, in % by weight, as follows: Si: 0.6 - 1.1, Fe: up to 0.40, Cu: 0.50 - 0.8, Mg: 0.50 - 0.9, Mn: 0.10 - 0.45 optionally Cr: 0.06 - 0.10, Zn: up to 0.15, Ti: up to 0.05, V: up to 0.05, other elements or impurities < 0.05 each and < 0.15 total, remainder aluminium.

[0067] Example

[0068] Table 1 gives the composition of alloys A, B, C, and D according to the invention, which were cast by semi-continuous vertical casting, as well as their homogenization and hot rolling conditions, first on a reversible rolling mill and then on a tandem rolling mill. In the compositions of Table 1, the other elements or impurities have a content of less than 0.05 each and less than 0.15 in total.

[0069] Table 1]

[0070] The treated sheets underwent cold rolling at different rolling rates, followed by final heat treatments at various temperatures and durations. Table 2 shows the results of the static mechanical properties in the transverse-longitudinal direction, specifically the yield strength, elongation, and electrical conductivity obtained as a function of the cold rolling and final heat treatment conditions.

[0071] Table 2 also provides typical values ​​corresponding to AA3003 or AA1050 alloy products according to the prior art.

[0072] The examples according to the invention demonstrate either a good compromise between electrical conductivity and formability, with, in particular, elongation rates exceeding 25%, or a good compromise between electrical conductivity and tensile strength, with, in particular, yield strengths exceeding 145 MPa. These values ​​are due to optimal combinations of parameters such as the final heat treatment conditions or the cold rolling rate, which allow these favorable compromises to be achieved. [Table 2]

Claims

DEMANDS 1. A process for manufacturing an aluminum alloy sheet in which a) an aluminum alloy is prepared with the composition, in % by weight Si: 0.4 - 1.4, Fe: up to 0.5, Cu: up to 0.8, Mn: 0.08 - 0.8 and / or Cr: 0.06 - 0.5, with Mn + Cr + Zn > 0.10, Mg: 0.2 - 0.9, Zn: up to 0.5, Ti: up to 0.05, V: up to 0.05, other elements or impurities < 0.05 each and < 0.15 total, remainder aluminum, b) it is cast in the form of a rolling slab by vertical semi-continuous casting, c) said rolling slab is homogenized at a temperature of 400 to 600 °C for a period of 1 to 24 hours, d) said homogenized slab is hot-rolled to a final exit temperature greater than or equal to 230 °C, e) Optionally, said cast, homogenized and hot-rolled sheet is cold-rolled with a reduction of up to 95% and a final heat treatment is carried out on said cast, homogenized, hot-rolled and cold-rolled sheet at a temperature of 150 to 400 °C and for a duration of 1 to 24 hours, characterized in that the final thickness of the sheet is 0,5 mm to 10 mm and in that the transformation conditions are determined so as to obtain at the end of step d or step e if it is carried out an IACS conductivity of at least 47% and to obtain in the transverse-long direction, either a yield strength Rp0.2 of at least 35 MPa and an elongation A% of at least 25%, or a yield strength Rp0.2 of at least 145 MPa and an elongation A% of at least 5%.

2. Method according to claim 1 wherein Mn + Cr > 0.

10.

3. Aluminum alloy sheet, 0.5 to 10 mm thick, with the following composition (in wt%): Si: 0.4–1.4, Fe: up to 0.5, Cu: up to 0.8, Mn: 0.08–0.8 and / or Cr: 0.06–0.5, with Mn + Cr + Zn > 0.10, Mg: 0.2–0.9, Zn: up to 0.5, Ti: up to 0.05, V: up to 0.05, other elements or impurities < 0.05 each and < 0.15 total, remaining aluminum, obtainable by the process according to claim 1 or claim 2, and having an electrical conductivity (IACS) of at least 47% and, in the long transverse direction, a yield strength (Rp0.2) of at least 35 MPa and an elongation (A) % of at least 25%.

4. Aluminum alloy sheet with a thickness of 0.5 to 10 mm, composition in % by weight: Si: 0.4 - 1.4, Fe: up to 0.5, Cu: up to 0.8, Mn: 0.08 - 0.8 and / or Cr: 0.06 - 0.5, with Mn + Cr + Zn > 0.10, Mg: 0.2 - 0.9, Zn: up to 0.5, Ti: up to 0.05, V: up to 0.05, other elements or impurities < 0.05 each and < 0.15 total, remainder aluminium, capable of being obtained by the process according to claim 1 or claim 2 and having an electrical conductivity IACS of at least 47% and, in the long cross direction, a yield strength Rp0.2 of at least 145 MPa and an elongation A% of at least 5%.

5. Sheet according to claim 3 having a composition at the intersection of the composition of the alloy of claim 3 and the alloy AA6082, having an electrical conductivity IACS of at least 53% and, in the long cross direction, a yield strength Rp0.2 of at least 40 MPa and preferably at least 80 MPa and an elongation A% of at least 25% and preferably at least 30%.

6. Sheet according to claim 4 having a composition at the intersection of the composition of the alloy of claim 4 and the AA6082 alloy, having an electrical conductivity IACS of at least 53% and, in the long cross direction, a yield strength Rp0.2 of at least 150 MPa and preferably at least 180 MPa and an elongation A% of at least 8% and preferably at least 14%.

7. Sheet according to claim 3 having a composition at the intersection of the composition of the alloy of claim 3 and the AA6005A alloy, having an electrical conductivity IACS of at least 53% and, in the long cross direction, a yield strength Rp0.2 of at least 36 MPa and preferably at least 38 MPa and an elongation A% of at least 29% and preferably at least 30%.

8. Sheet according to claim 4 having a composition at the intersection of the composition of the alloy of claim 4 and of the AA6111 alloy, having an electrical conductivity IACS of at least 51% and, in the long cross direction, a yield strength Rp0.2 of at least 140 MPa and preferably at least 190 MPa and an elongation A% of at least 9% and preferably at least 12%.

9. Use of an aluminum alloy sheet according to claim 3, 5 or 7, for applications of heat sinks, battery cooling channels, stamped cooling panels.

10. Use of an aluminium alloy sheet according to claim 4, 6 or 8 for applications of conductive bars, flat screen cooling plates, refrigerated plates, squirrel cage rotors used in particular in induction motors, roof coils.

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