Method for manufacturing aluminium alloy sheets having improved abrasion resistance and / or improved conductivity
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- CONSTELLIUM ISSOIRE
- Filing Date
- 2026-01-21
- Publication Date
- 2026-07-30
Smart Images
Figure FR2026050051_30072026_PF_FP_ABST
Abstract
Description
[0001] Description
[0002] Title of the invention: Method for manufacturing aluminum alloy sheets exhibiting improved abrasion resistance and / or conductivity
[0003] Scope of the invention
[0004] The present invention relates to Al-Mg-Si alloys and their manufacturing process. The invention particularly relates to sheets exhibiting improved abrasion resistance. The invention also relates to aluminum alloy products with high electrical and thermal conductivities.
[0005] State of the art
[0006] 6xxx series alloys (Al-Mg-Si) are described as "structurally hardening," meaning they acquire their mechanical properties through the precipitation of the alloying elements (Mg, Si). It is known that, to obtain these mechanical properties, hot forming by rolling or extrusion is followed by solution heating, quenching, and tempering. These operations, usually performed separately, respectively dissolve the alloying elements, maintain them as a supersaturated solid solution at room temperature, and finally precipitate them in a controlled manner. In the case of sheet or strip products, the tempering process that provides maximum mechanical strength is designated T6, where forming by rolling or extrusion is followed by separate solution heating and quenching.
[0007] For the use of such a product, the parameters that govern the user's choice are essentially the static mechanical characteristics, that is to say, the breaking strength R m , the elastic limit R p o,2, and elongation at break A. Other parameters that come into play, depending on the specific needs of the intended application, are corrosion resistance, crack propagation resistance, toughness, dimensional stability after cutting or welding, abrasion resistance, fatigue resistance, and electrical or thermal conductivity. For each intended use, a suitable compromise must be found between these different properties.
[0008] The ability to industrially produce laminated products of consistent quality with the simplest possible manufacturing process and the lowest possible production cost is also an important factor in the choice of material.
[0009] Abrasion resistance is particularly important for many applications, including the manufacture of granular material skip bottoms, flooring, sprockets for conveyor systems, sprockets for bicycles, motorcycles, or cars, conveyor floors, tracks for construction machinery, various coatings, and brake shoes. A granular material skip most often comprises a bottom, typically a flat or curved bottom 1, and a plurality of side walls 2, 4 designed to contain the granular material to be transported; typically, a skip has a rectangular shape and two sets of two side walls, at least one of which 2 can be opened to discharge the granular material by tilting the skip using a cylinder 3 (see Figure 1).For example, skips for granular materials are typically unloaded by tipping: the skip is tilted, and the granular material flows out through an opening. This opening can be a side hatch. The flow can also occur through an opening in the bottom of the skip. In all cases, during this flow, the granular material slides along the bottom of the skip. This leads to wear by abrasion.
[0010] Patent application W02006 / 035155 describes a skip for the transport, storage or handling of granular material comprising a bottom and side walls, characterized in that at least a part of the bottom comprises a sheet metal having been printed by rolling one or more relief patterns on one face, said sheet metal being arranged so that during transport or during unloading of the granular material, said pattern is in contact with said granular material.
[0011] Patent application WO2018 / 104004 relates to a process for manufacturing an abrasion-resistant aluminum alloy rolled product comprising the steps of: (a) supplying an aluminum alloy rolling material having Mg 4.20% to 5.5%, Mn 0.50% to 1.1%, Fe up to 0.40%, Si up to 0.30%, Cu up to 0.20%, Cr up to 0.25%, Zr up to 0.25%, Zn up to 0.30%, Ti up to 0.25%, unavoidable impurities and remaining aluminum; (b) heating the rolling material; (c) hot rolling the rolling material to an intermediate thickness in a range of 15 mm to 40 mm; (d) hot rolling the rolling material from an intermediate thickness to a final thickness in a range of 3 mm to 15 mm and in which the exit temperature of the hot rolling mill is in a range of 130 to 285 °C; (e) cooling the hot-rolled material to ambient temperature.
[0012] Patent application WO2018206696 relates to a process for manufacturing a rolled aluminum alloy sheet product comprising: (a) casting an ingot of an Al-Si-Mg aluminum alloy comprising, by weight %: Si 1.0% to 1.50%, Mg 0.10% to 0.40%; (b) heating the ingot to a temperature above 550 °C; maintaining the ingot at a temperature above 550 °C for at least about (4) hours; cooling the ingot to a temperature in the range of 460 °C to 520 °C; and maintaining the ingot at a temperature in the range of 460 °C to 520 °C for less than (6) hours; (c) hot rolling the ingot in one or more rolling passes to an intermediate thickness in a range of 15 mm to 40 mm and in which the exit temperature of the hot rolling mill is in a range of 370 °C to 480 °C;(d) further hot rolling from an intermediate thickness in one or more rolling passes to a final hot-rolled thickness, wherein the hot rolling mill outlet temperature is between 310 °C and 400 °C; (e) cooling the hot-rolled material to the final hot-rolled thickness from the hot rolling mill outlet temperature to ambient temperature; (f) cold rolling of the hot-rolled product to a final cold-rolled product thickness. Patent application EP3842561 relates to a process for manufacturing a rolled aluminum alloy product with a thickness of at least 1 mm, comprising the following steps: semi-continuous casting of an aluminum alloy with a thickness of at least 250 mm; homogenization of the rolling ingot at a maximum metal temperature (PMT) and said aluminium alloy having a specific energy associated with a DSC signal of less than 2 J / g in absolute value;hot rolling of the rolling ingot in several hot rolling passes into a hot rolled product having a final rolling gauge of at least 1 mm, the hot rolled product having, during at least one of the last three rolling passes, a temperature below 50 °C below PMT; quenching of the hot rolled product to the final rolling gauge from the exit temperature of the hot rolling mill down to less than 175 °C; optionally stress relieving of the quenched and hot rolled product to the final rolling gauge; and aging of the quenched hot rolled product and optionally stress relieving.
[0013] Sheet metal used for flooring is also subject to wear. Many models of sheet metal with repetitive embossed patterns are already available on the market. These patterns are described, for example, in the NF-EN-1386 standard. The "rice grain" pattern, described in patent FR2747948, is also used for manufacturing aluminum alloy sheets for industrial flooring, which offer satisfactory performance properties, notably because they have good wear resistance and provide friction contact conditions that allow pedestrians to walk without risk of slipping and forklifts to move without skidding.
[0014] For many aluminum alloy products, electrical and thermal conductivity properties are also 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.
[0015] 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.
[0016] The present invention aims to provide an improved rolled product in aluminium alloy, intended in particular for the production of abrasion-resistant sheets and / or having high electrical and thermal conductivity, and having satisfactory mechanical properties for this application and whose manufacturing process is economical.
[0017] Object of the invention
[0018] A first object of the invention is a method for manufacturing a rolled product made of aluminum alloy, comprising the following successive steps:
[0019] (a) casting in the form of a rolling plate an aluminium alloy of the 6XXX series, (b) heating the rolling plate to a temperature of 520 °C to 600 °C, (c) first hot rolling of the thus heated rolling plate in one or more passes to an intermediate thickness sheet of 12 to 40 mm, preferably 15 to 30 mm, the hot rolling inlet temperature T1 being preferably 490 °C to 570 °C and the hot rolling outlet temperature T2 being preferably 470 °C to 530 °C,
[0020] (d) second hot rolling optionally preceded by quenching the intermediate thickness sheet in one or more passes to a hot rolling exit thickness of 2 mm to 15 mm, the temperature T3 of the intermediate thickness sheet when step (d) begins being 410 °C to 510 °C, and the hot rolling exit temperature T4 being 170 °C to 240 °C, wherein the sheet is cooled from T3 to T4 with a cooling rate of at least 165 °C / min,
[0021] (e) winding of the hot rolling output thickness sheet and cooling to ambient temperature, (f) optionally cold rolling of the hot rolling output thickness sheet with a reduction ratio of 10% to 60% and / or heat treatment at a temperature of 150°C to 250°C.
[0022] A second object of the invention is an abrasion-resistant laminated product obtainable by the process according to the invention which has an elastic limit RpO2 in the TL direction of at least 200 MPa, determined by a tensile test according to standard NF EN ISO 6892-1 2016.
[0023] A third object is a laminated product obtainable by the process according to the invention which has an electrical conductivity IACS of at least 50%, or at least 51%, or at least 52%, or at least 53%, or at least 55%, or at least 56%, or at least 57%, or at least 58%.
[0024] Another object of the invention is the use of an abrasion-resistant laminated product according to the invention or obtained by a process according to the invention for the production of tipper bottoms for granular materials or floors or sprockets for conveyor systems or sprockets for bicycle or motorcycle or car, or conveyors or tracks for construction machinery or floor coverings or ship deck plates or railway track components or machine guard panels or lining for hoppers or chutes and bins or brake shoes.Another object of the invention is the use of a laminated product according to the invention or obtained by a process according to the invention for the production of heat sinks 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, refrigerated plates, squirrel cage rotors used especially in induction motors, roof coils.
[0025] Description of the figures
[0026] Figure 1 shows a skip for granular material made of sheet metal and profiles. Figure 2 schematically shows one embodiment in a temperature / temperature diagram.
[0027] Figure 3 schematically shows one embodiment in a T time / T temperature diagram.
[0028] Figure 4 schematically shows one embodiment in a time / temperature diagram. Figure 5 schematically shows one embodiment in a time / temperature diagram.
[0029] Figure 6 shows the relationship between the yield strength in the TL direction and the abrasion measured by the Taber test.
[0030] Figure 7 shows the relationship between the yield strength in the TL direction and the conductivity.
[0031] Description of the invention
[0032] All aluminum alloys mentioned below are designated according to the rules and designations defined by The Aluminum Association in the Registration Record Series that it publishes regularly, unless otherwise stated.
[0033] The metallurgical states referred to are designated according to the European standard EN-515 1993 unless otherwise stated.
[0034] All alloy compositions are provided as % by weight (% by weight).
[0035] Unless otherwise stated, the static mechanical characteristics, i.e. the ultimate tensile strength Rm, the tensile yield strength Rp0.2, and the total elongation, also called elongation at break, are determined by a tensile test according to the standard NF EN ISO 6892-1 2016, the location of the parts and their direction being defined in the standard EN 4852016.
[0036] Unless otherwise stated, the definitions in standard EN 122582012 apply.
[0037] 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-sectional area of one square millimeter.
[0038] The applicant has found, surprisingly, that rolled products of Al-Mg-Si alloy which show a very good compromise of properties, including mechanical properties, abrasion resistance and / or conductivity, can be manufactured using a simplified process in which solution treatment and quenching are carried out during the hot rolling process.
[0039] The process according to the invention can be implemented on Al-Mg-Si alloys of type 6XXX in a wide range of chemical composition, in % by weight: Si 0.2 - 1.3; Mg 0.5 - 1.4; Fe < 0.7; Cu < 0.9; Mn < 1.0; Cr < 0.4; Zn < 0.25; Ti < 0.15; unavoidable impurities: each < 0.05%, total < 0.15%, remainder aluminium.
[0040] The applicant also realized that it is possible to improve wear resistance and / or conductivity through the development of more abrasion-resistant alloys or materials of the 6XXX family, without increasing manufacturing costs, through a process that does not involve solution treatment and quenching after hot rolling, but in which solution treatment and quenching are carried out during the hot rolling process.
[0041] The inventors found that, surprisingly, alloy sheets from the 6XXX series, which had not undergone solution treatment and quenching after hot rolling but whose processing conditions had been carefully chosen, exhibit excellent abrasion resistance. This process can be used for the manufacture of embossed sheets. According to standard EN 12258-1, those skilled in the art understand "embossed sheet" to mean "sheet that has been imprinted with a raised pattern on one face by rolling."
[0042] According to the invention, the manufacturing process for a rolled aluminum alloy product comprises the successive steps of casting, heating, hot rolling to an intermediate thickness sheet, hot rolling to the final hot-rolling thickness sheet, and cooling to ambient temperature, optionally cold rolling and / or heat treatment at a temperature of 170°C to 320°C. The process according to the invention does not include, after hot rolling, solution treatment and / or quenching.
[0043] In the manufacturing process according to the invention, the rolled aluminum alloy product is typically an abrasion-resistant rolled product.
[0044] In a step (a), a 6XXX series aluminum alloy is cast in the form of a rolling plate.
[0045] Preferably, the alloy of the 6XXX series has the following composition, expressed as a percentage by weight:
[0046] If 0.2 - 1.3
[0047] Mg 0.5 - 1.4
[0048] Fe < 0.7
[0049] Cu < 0.9
[0050] Mn < 1.0
[0051] Cr < 0.4
[0052] Zn < 0.25
[0053] Ti < 0.15
[0054] unavoidable impurities: each < 0.05%, total < 0.15%, remainder aluminum.
[0055] The silicon content is preferably at least 0.3% or 0.4% and / or at most 1.1% or 1.0%, or 0.9% or 0.8%. In one embodiment, the silicon content is 0.4% to 0.8%. In another embodiment, the silicon content is 0.7% to 1.3%. The magnesium content is preferably at least 0.6% or 0.7% and / or at most 1.3% or 1.2%. In one embodiment, the magnesium content is 0.8% to 1.2%. In another embodiment, the minimum magnesium content is 0.9%.
[0056] The Fe content is preferably no more than 0.6%. In one embodiment, the Fe content is 0.3 to 0.7%. In another embodiment, the Fe content is 0.1 to 0.5%.
[0057] The Cu content is preferably at most 0.8% or 0.7%. In one embodiment, the Cu content is at most 0.5%. In another embodiment, the Cu content is at most 0.3%. In another embodiment, the Cu content is from 0.1% to 0.4% or from 0.2% to 0.4%. In one embodiment, the Cu content is at most 0.2%.
[0058] The manganese content is preferably at most 0.9% or 0.8%. In one embodiment, the manganese content is at most 0.4%, 0.3%, or 0.2%. In one embodiment, the manganese content is at least 0.05%, 0.08%, or 0.1%. In one embodiment, the manganese content is from 0.4% to 1.0%.
[0059] The Cr content is preferably no more than 0.35% or 0.30%. In one embodiment, the Cr content is from 0.05% to 0.25%. In another embodiment, the minimum Cr content is 0.06%.
[0060] The Zn content is preferably at most 0.20% or 0.15%. In one embodiment the Zn content is from 0.01 to 0.20% or from 0.06 to 0.19%.
[0061] The Ti content is preferably at most 0.12% or 0.10%. In one embodiment the Ti content is from 0.01 to 0.10%.
[0062] The other elements are unavoidable impurities, the maximum content of each being 0.05% and 0.15% in total.
[0063] In an advantageous embodiment, the 6XXX series alloy has the following composition, expressed as a percentage by weight:
[0064] If 0.2 - 0.8
[0065] Mg 0.9 - 1.4
[0066] Fe < 0.7
[0067] Cu < 0.9
[0068] Mn < 0.4
[0069] Cr 0.06 - 0.4
[0070] Zn < 0.25Ti < 0.15
[0071] unavoidable impurities: each < 0.05%, total < 0.15%, remainder aluminum.
[0072] In one embodiment, the 6XXX series alloy is selected from the AA6005, AA6101, AA6061, AA6063 and AA6082 alloys, according to the designation of The Aluminum Association.
[0073] The chosen composition makes it possible in particular to obtain improved abrasion resistance and / or improved conductivity and satisfactory mechanical properties for the production of skips and to use an economical manufacturing process, not requiring solution treatment after hot rolling.
[0074] In step (b), the rolling plate is heated to a temperature of 520 °C to 600 °C. In one embodiment, the heating temperature of the rolling plate is at least 530 °C, or at least 540 °C, or at least 550 °C, or at least 560 °C, and / or at most 590 °C, or at most 580 °C, or at most 570 °C. In one embodiment, the heating is a homogenization process lasting from 4 to 48 hours. In another embodiment, the heating is a treatment to reach the hot rolling start temperature. In one embodiment, the heating temperature is from Ts - 50 °C to Ts, where Ts is the solidus temperature of the alloy.
[0075] In a first hot rolling operation (c), the sheet is hot-rolled in one or more rolling passes to an intermediate thickness of 12 to 40 mm, preferably 15 to 30 mm, the inlet temperature T1 of the first hot rolling operation being preferably 490 °C to 570 °C and the outlet temperature T2 of the first hot rolling operation being preferably 470 °C to 530 °C. Hot rolling to the intermediate thickness is typically carried out with one or more reversible rolling mills.
[0076] In one embodiment, the inlet temperature T1 of the first hot rolling for the rolling pass(es) up to an intermediate thickness sheet is at least 500 °C, or is at least 510 °C, or is at least 520 °C, or is at least 530 °C, or is at least 540 °C, and / or is at most 550 °C, or is at most 540 °C, or is at most 530 °C, or is at most 520 °C, or is at most 510 °C.
[0077] In one embodiment, the exit temperature T2 of the first hot rolling operation for the rolling pass(es) to an intermediate thickness plate is at least 480 °C, or at least 490 °C, or at least 500 °C, or at least 510 °C, or at least 520 °C, and / or at most 510 °C, or at most 500 °C, or at most 490 °C, or at most 480 °C. In a second hot rolling operation, optionally preceded by quenching the intermediate thickness plate (d), the intermediate thickness plate is hot-rolled after optional quenching in one or more rolling passes to an exit thickness of 3 mm to 15 mm, the temperature T3 of the intermediate thickness plate when step (d) begins being 410 °C. at 510 °C and the T4 outlet temperature of the hot rolling mill being 170 °C to 240 °C. The sheet is cooled from T3 to T4 with a cooling rate of at least 165 °C / min.Preferably, the sheet is cooled from T3 to T4 with a cooling rate of at least 200 °C / min, or at least 250 °C / min, or at least 300 °C / min, or at least 350 °C / min, or at least 400 °C / min. The second hot rolling from the intermediate thickness to the hot-rolling exit thickness is typically carried out on a tandem rolling mill comprising two, three, four, or five stands. The optional quenching preceding the second hot rolling can be performed by any means ensuring sufficiently rapid cooling, such as immersion, spraying, forced convection, or a combination thereof. As an example, the sheet can be conveyed through a spray-quenching cell.Quenching can be carried out using the rolling emulsion spray bars at the outlet of the mill used to achieve the intermediate thickness, typically a reversible mill, or using a spray quenching cell, possibly followed by a natural or forced convection quenching cell, or using the rolling emulsion spray bars at the inlet of the mill used to achieve the hot-rolling out-of-wall thickness, typically the first stand of a tandem mill. Quenching is not carried out at the hot-rolling out-of-wall thickness.
[0078] In one embodiment, a pattern is printed by engraving during the second hot rolling, typically in the last stand of a tandem rolling mill.
[0079] The target cooling rate can be achieved by combining rolling conditions such as rolling speed, amount of oil sprayed and optionally quenching conditions.In one embodiment, the cooling from T3 to T4 is achieved by using a spray cooling cell positioned between two rolling passes, typically between two stands of a tandem rolling mill, or by using the rolling emulsion spray ramps of the mill used to achieve the hot rolling exit thickness, typically the exit of the first stand of a tandem rolling mill and / or the inlet of the second stand of a tandem rolling mill and / or the exit of the second stand of a tandem rolling mill and / or the inlet of the third stand of a tandem rolling mill and / or the exit of the third stand of a tandem rolling mill and / or the inlet of the fourth stand of a tandem rolling mill and / or the exit of the fourth stand of a tandem rolling mill and / or the inlet of the fifth stand of a tandem rolling mill.The duration t during which the sheet metal is at a temperature of T3 to T4 is preferably at most 2 minutes or at most 1.5 minutes or at most 1.2 minutes or at most 1 minute or at most 0.8 minutes and preferably at most 0.6 minutes.
[0080] According to the invention, after hot rolling, the rolled aluminum alloy product is not subjected to solution heating and / or quenching. If one or more optional cold rolling and / or heat treatment steps at a temperature of 150 °C to 250 °C are performed, the rolled aluminum alloy product is, of course, also not subjected to solution heating / quenching before or after these steps.
[0081] In one embodiment, the temperature T3 of the intermediate thickness sheet when step (d) begins is at least 420 °C, or is at least 430 °C, or is at least 440 °C, or is at least 450 °C, or is at least 460 °C, or is at least 470 °C, or is at least 480 °C, or is at least 490 °C, and / or is at most 480 °C, or is at most 470 °C, or is at most 460 °C.
[0082] In one embodiment, the hot rolling exit temperature T4 for the rolling pass(es) up to a hot rolling exit thickness plate is at least 180 °C, or is at least 190 °C, or is at least 200 °C, or is at least 210 °C, and / or is at most 230 °C, or is at most 220 °C, or is at most 210 °C, or is at most 200 °C.
[0083] In step (e), the hot-rolled sheet of the required thickness is wound and cooled to ambient temperature. In one embodiment, the sheet of the required thickness is wound after hot rolling, and then the wound coil is cooled to ambient temperature, either naturally or by forced convection. In one embodiment, the winding after hot rolling and the cooling of the coil allow for tempering, and no further tempering is performed. In another embodiment, the winding after hot rolling and the cooling of the coil allow for pre-tempering, and further tempering is then performed, typically after cold rolling passes.
[0084] Different embodiments are shown in Figures 2 to 5. Figure 2 illustrates an embodiment in which the optional quenching step is carried out just before the second hot rolling, starting at temperature T3. Figure 3 illustrates an embodiment in which the cooling from T3 to T4 is carried out during the second hot rolling. Figure 4 illustrates an embodiment in which the optional quenching step is carried out shortly after the first hot rolling, at temperature T3. It should be noted in particular for this embodiment that if the time t is too long, the embodiment may not be according to the invention. Figure 5 illustrates an embodiment in which the cooling from T3 to T4 is carried out during the second hot rolling and in which the first hot rolling is carried out on two successive reversible rolling mills.
[0085] In an optional step (f), the hot-rolled sheet is cold-rolled with a reduction ratio of 10% to 60% and / or a heat treatment is carried out at a temperature of 150°C to 250°C. In one embodiment of step (f), the reduction ratio of the optional cold-rolling step is at least 15%, or at least 20%, or at least 25%, or at least 30%, or at least 40%, or at least 50%, and / or at most 55%, or at most 55%, or at most 40%, or at most 35%, or at most 30%, or at most 25%, or at most 20%.In one embodiment of step (f), the heat treatment temperature is at least 155 °C, or is at least 160 °C, or is at least 165 °C, or is at least 170 °C, or is at least 175 °C, or is at least 180 °C, or is at least 185 °C, or is at least 190 °C, and / or is at most 245 °C, or is at most 240 °C, or is at most 235 °C, or is at most 230 °C, or is at most 225 °C, or is at most 220 °C, or is at most 215 °C, or is at most 210 °C, or is at most 205 °C, or is at most 200 °C, or is at most 195 °C, or is at most 190 °C, or is at most 185 °C, or is at most 180 °C, or is at most 175 °C, or is at most 170 °C, or is at most 165 °C, or is at most 160 °C. In one embodiment of step (f), the heat treatment time is at least 1 hour, or at least 2 hours, or at least 3 hours, or at least 4 hours and / or at most 12 hours, or at most 11 hours, or at most 10 hours, or at most 9 hours.In one embodiment, heat treatment at a temperature of 150 °C to 250 °C enables the generation of income or supplementary income.
[0086] In one embodiment, the temperature and / or duration of heat treatment are chosen to obtain a favorable balance between mechanical strength and conductivity.
[0087] The heat treatment can be described by a temperature function T° c (t) as a function of time. This function T° c (t) is such that, according to the invention, the maximum temperature T ma The temperature reached during the heat treatment is between 150 °C and 250 °C. The heat treatment time is adjusted to obtain an equivalent time calculated at 170 °C. eq 170 ° cadjusted according to the desired mechanical resistance and conductivity. This equivalent duration is calculated using a formula based on the integration of the temperature function. c (t) with respect to time over the heat treatment time interval. The formula is as follows:
[0088]
[0089] " > "
[0090] The temperature is expressed in degrees Celsius (°C) and the time in hours.
[0091] In an embodiment intended to obtain a conductivity of at least 57% IACS and a yield strength Rp0.2 TL of at least 210 MPa, t eq 170 ° c is at least 20 h. In an embodiment intended to obtain a conductivity of at least 57.8% IACS and a yield strength Rp0.2 of at least 150 MPa, t eq 170 ° c is at least 500 hours.
[0092] In one embodiment t eq 170 ° cis at least 10 hours or at least 20 hours or at least 30 hours or at least 40 hours or at least 50 hours or at least 60 hours or at least 70 hours or at least 80 hours or at least 90 hours.
[0093] In one embodiment, a pattern is imprinted by engraving during cold rolling. Numerous sheet metal designs with repetitive embossed patterns are already available on the market. These patterns are described, for example, in the NF-EN-1386 standard. The "rice grain" pattern is advantageous.
[0094] In one embodiment, the surface of the abrasion-resistant laminated product according to the invention can be described as the as-rolled surface, where the rolling lines, parallel to the rolling direction, are visible, corresponding to peaks and valleys parallel to the rolling direction. In another embodiment, the surface of the abrasion-resistant laminated product according to the invention can be described as a surface imprinted with a pattern.
[0095] The laminated product obtained by the process according to the invention preferably has a thickness of 3 to 10 mm.
[0096] Surprisingly, although the abrasion-resistant rolled product according to the invention generally has lower mechanical strength than products in a cold-rolled state that have undergone solution quenching / quenching and tempering after hot rolling, its abrasion resistance is equivalent or even lower. Furthermore, the abrasion-resistant rolled product according to the invention has superior abrasion resistance compared to 5XXX alloy products according to the prior art. Advantageously, the mass loss in mg under Taber test conditions of 60 rpm, 4000 rpm, 10 N applied force, ambient temperature, rolling motion, 31.75 mm friction radius, U = 200 mm, and H-22 friction roller, is less than 350 mg, preferably less than 320 mg, or 300 mg, and preferably 280 mg, 270 mg, 260 mg, or 250 mg.
[0097] Advantageously, the yield strength Rp02 in the TL direction of the abrasion-resistant laminated product according to the invention is at least 200 MPa, preferably at least 210 MPa and preferably at least 200 MPa and preferably at least 230 MPa.
[0098] In an advantageous embodiment, the abrasion-resistant laminated product according to the invention has a mass loss in mg under Taber test conditions of 60 rpm, number of revolutions 4000, applied force 10 N, ambient temperature, type of movement: rolling, friction radius: 31.75 mm, II = 200 mm, friction roller H-22, less than 250 mg and a yield strength RpO2 in the TL direction of at least 200 MPa.
[0099] In one embodiment, the laminated product according to the invention, which is typically abrasion resistant, has an electrical conductivity IACS of at least 50%, or at least 51%, or at least 52%, or at least 53%, or at least 55%, or at least 56%, or at least 57%, or at least 58%.
[0100] In one embodiment, the laminated product according to the invention, which is typically abrasion-resistant, has an electrical conductivity IACS of at least 55%, preferably at least 57% and preferably at least 58%, and mechanical properties such that the yield strength Rp02 in the TL direction is at least 150 MPa, preferably at least 160 MPa and preferably at least 170 MPa and preferably at least 180 MPa and / or the resistance Rm in the TL direction is at least 170 MPa, preferably at least 180 MPa and preferably at least 190 MPa and preferably at least 200 MPa.
[0101] In one embodiment, the laminated product according to the invention, which is typically abrasion-resistant, has an electrical conductivity IACS of at least 50%, preferably at least 51% and preferably at least 52%, and mechanical properties such that the yield strength Rp02 in the TL direction is at least 190 MPa, preferably at least 200 MPa and preferably at least 210 MPa and preferably at least 220 MPa and / or the resistance Rm in the TL direction is at least 210 MPa, preferably at least 220 MPa and preferably at least 230 MPa and preferably at least 240 MPa.
[0102] In one embodiment, the laminated product according to the invention, which is typically abrasion-resistant, has an electrical conductivity IACS of at least 55%, preferably at least 56% and preferably at least 57%, and mechanical properties such that the yield strength Rp02 in the TL direction is at least 170 MPa, preferably at least 180 MPa and preferably at least 190 MPa and preferably at least 200 MPa and / or the resistance Rm in the TL direction is at least 200 MPa, preferably at least 210 MPa and preferably at least 220 MPa and preferably at least 230 MPa.
[0103] In one embodiment, the laminated product according to the invention, which is typically abrasion-resistant, has an electrical conductivity IACS of at least 54%, preferably at least 55% and preferably at least 56%, and mechanical properties such that the yield strength Rp02 in the TL direction is at least 210 MPa, preferably at least 220 MPa and preferably at least 230 MPa and preferably at least 240 MPa and / or the resistance Rm in the TL direction is at least 220 MPa, preferably at least 230 MPa and preferably at least 240 MPa and preferably at least 250 MPa.
[0104] In an advantageous embodiment, the laminated product according to the invention, which is typically abrasion-resistant, is an AA6005 or AA6101 alloy and has an IACS electrical conductivity of at least 50%, or at least 51%, or at least 52%, or at least 53%, or at least 55%, or at least 56%, or at least 57%, or at least 58%.
[0105] The invention also relates to a method for manufacturing a granular material skip in which an abrasion-resistant laminated product is obtained by the method according to the invention and said abrasion-resistant laminated product is shaped and / or assembled to form a granular material skip comprising said abrasion-resistant laminated product.
[0106] The invention also relates to a skip for granular material comprising an abrasion-resistant laminated product obtained by the process according to the invention.
[0107] According to the invention, the abrasion-resistant laminated product can be placed at the bottom of the skip so as to be in contact with the granular material when the skip is loaded. The abrasion-resistant laminated product can be placed over the entire surface of the skip bottom, or only on the part closest to the hatch through which the granular material is discharged. For the purposes of this invention, the term "bottom" should be understood as meaning the part of the skip on which the granular material exerts a downward force (when the skip is in a horizontal position (transport position)), while the term "wall" should be understood as meaning the part of the skip on which the granular material exerts a more horizontal force. The bottom and the walls can be separate parts (joined, for example, by welding or bolting), or constitute a single curved shape (whether assembled or not).What is important is that at least a portion of the bottom of the skip, namely the portion over which the granular material slides during unloading, is covered with an abrasion-resistant laminated product according to the invention. In one embodiment, the skip according to the invention is characterized in that the abrasion-resistant laminated product covers the entire surface of the bottom of the skip, or only a portion of the surface of said bottom over which the granular material slides during unloading.
[0108] The use of the abrasion-resistant laminated product is advantageous in many applications including the production of tipper bottoms for granular materials, floors, sprockets for conveyor systems, sprockets for bicycles or motorcycles or cars, conveyors, tracks for construction machinery, floor coverings, ship deck plates, railway track components, machine protection panels, lining for hoppers, chutes and bins or brake shoes.
[0109] The use of the laminated product according to the invention, which is typically abrasion-resistant, is also advantageous for 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, roof coils.
[0110] The following examples describe, by way of illustration, advantageous embodiments of the invention. These examples are not intended to be limiting.
[0111] Example
[0112] In this example, the mechanical properties and abrasion resistance of alloy sheets according to the invention, obtained according to the process of the invention or not, were compared and compared.
[0113] Table 1 shows the composition of the alloys cast in the form of rolling slabs, in % by weight. [Table 1] - Chemical composition (% by weight)
[0114] < < < < < < < < <
[0115]
[0116] The rolling plates were processed by hot rolling and optionally by cold rolling. The processing conditions are given in Table 2. Conditions E-1, F-1, H-1, I-1, and J-1 are according to the invention. Condition C-1 is shown in Figure 4. Conditions D-1 and J-1 are shown in Figure 2. Conditions E-1, F-1, H-1, and I-1 are shown in Figure 5.
[0117] [Table 2] Transformation conditions
[0118]
[0119] * Solution treatment, quenching and tempering after cold rolling. The mechanical properties of the resulting sheets were characterized. The results are provided in Table 3.
[0120] [Table 3] - Mechanical properties
[0121]
[0122] In an abrasion resistance test, samples were tested using a standardized Taber setup in which two abrasive wheels with a specified surface area are rotated with a defined force on a rotating material sample. The two abrasive wheels rotate in opposite directions, meaning that the material is abrasiond transversely. The weight loss is measured after 4000 revolutions and is referred to as the number of cycles (revolutions) as mass loss per revolution (mg / revolution). The applied test parameters were: 60 rpm, 4000 revolutions (resulting in a sliding path of 800 m), applied force 10 N, ambient temperature, type of motion: rolling, friction radius: 31.75 mm, U = 200 mm, friction roller H-22. For each series of tests, new friction rollers were used. The results are presented in Table 4. [Table 4] - Taber Test Results
[0123]
[0124] Conductivity measurements were performed on some samples. The results are presented in Table 5.
[0125] [Table 5] - Conductivity measurement results
[0126]
[0127] Heat treatments were carried out on the alloy product H-1 to optimize the compromise between conductivity and mechanical strength.
[0128] The results are presented in Table 6. [Table 6] - Results of conductivity measurements and mechanical properties obtained on test H-1 after heat treatment
[0129]
[0130] By modifying the heat treatment conditions, it is possible to achieve different compromises between mechanical strength and conductivity.
Claims
Demands 1. A process for manufacturing a rolled product of aluminum alloy, comprising the following successive steps: (a) cast in the form of a rolling plate of an aluminium alloy of the 6XXX series, (b) heating the rolling plate to a temperature of 520 °C to 600 °C, (c) first hot rolling of the rolling plate thus heated in one or more passes to an intermediate thickness of 12 to 40 mm, preferably 15 to 30 mm, the hot rolling inlet temperature T1 preferably being 490 °C to 570 °C and the hot rolling outlet temperature T2 preferably being 470 °C to 530 °C, (d) second hot rolling optionally preceded by quenching the intermediate thickness sheet in one or more passes to a hot rolling exit thickness of 2 mm to 15 mm, the temperature T3 of the intermediate thickness sheet when step (d) begins being 410 °C to 510 °C, and the hot rolling exit temperature T4 being 170 °C to 240 °C, wherein the sheet is cooled from T3 to T4 with a cooling rate of at least 165 °C / min, (e) winding of the hot-rolled sheet of the required thickness and cooling to ambient temperature, (f) optionally cold rolling of the hot rolling output thickness sheet with a reduction ratio of 10% to 60% and / or heat treatment at a temperature of 150°C to 250°C.
2. A method according to claim 1, wherein the rolled aluminum alloy product is an abrasion-resistant rolled aluminum alloy product.
3. A method according to claim 1 or claim 2, wherein the 6XXX series alloy has the following composition, in wt%, If 0.2 - 1.3 Mg 0.5 - 1.4 Fe < 0.7 Cu < 0.9 Mn < 1.0 Cr < 0.4 Zn < 0.25 Ti < 0.15 unavoidable impurities: each <= 0.05%, total <= 0.15%, remainder aluminium.
4. Process according to any one of claims 1 to 3 wherein the copper content is at most 0.5% and preferably from 0.1 to 0.4%.
5. A method according to any one of claims 1 to 3 wherein the 6XXX series alloy is selected from the alloys AA6005, AA6101, AA6061, AA6063 and AA6082, according to the designation of The Aluminum Association.
6. A method according to any one of claims 1 to 5 in which a pattern is printed by engraving during the second hot rolling or during the cold rolling.
7. A method for manufacturing a granular material container in which an abrasion-resistant laminated product is obtained by the method according to any one of claims 1 to 6, and said abrasion-resistant laminated product is shaped and / or assembled to form a granular material container comprising said abrasion-resistant laminated product.
8. Abrasion-resistant laminated product obtainable by the process according to any one of claims 1 to 7 which has a yield strength RpO2 in the TL direction of at least 200 MPa, determined by a tensile test according to standard NF EN ISO 6892-1 2016.
9. A rolled product according to claim 8 exhibiting a mass loss in mg under Taber test conditions of 60 rpm, 4000 rpm, 10 N applied force, ambient temperature, rolling motion, 31.75 mm friction radius, II = 200 mm, H-22 friction roller, of less than 250 mg.
10. A rolled product according to claim 8 characterized in that it is a raised plate obtained by the process according to claim 6.
11. Laminated product obtainable by the process according to any one of claims 1 to 5 which has an electrical conductivity IACS of at least 50%, or at least 51%, or at least 52%, or at least 53%, or at least 55%, or at least 56%, or at least 57%, or at least 58%.
12. Laminated product according to claim 11 having an electrical conductivity IACS of at least 55%, preferably of at least 57% and preferably of at least 58%, and mechanical properties such that the yield strength Rp02 in the TL direction is at least 150 MPa, preferably at least 160 MPa and preferably at least 170 MPa and preferably at least 180 MPa and / or the resistance Rm in the TL direction is at least 170 MPa, preferably at least 180 MPa and preferably at least 190 MPa and preferably at least 200 MPa.13.laminated product according to claim 11 having an electrical conductivity IACS of at least 50%, preferably of at least 51% and preferably of at least 52%, and mechanical properties such that the yield strength Rp02 in the TL direction is at least 190 MPa, preferably at least 200 MPa and preferably at least 210 MPa and preferably at least 220 MPa and / or the resistance Rm in the TL direction is at least 210 MPa, preferably at least 220 MPa and preferably at least 230 MPa and preferably at least 240 MPa.
14. Laminated product according to claim 11 having an electrical conductivity IACS of at least 54%, preferably of at least 55% and preferably of at least 56%, and mechanical properties such that the yield strength Rp02 in the TL direction is at least 210 MPa, preferably at least 220 MPa and preferably at least 230 MPa and preferably at least 240 MPa and / or the resistance Rm in the TL direction is at least 220 MPa, preferably at least 230 MPa and preferably at least 240 MPa and preferably at least 250 MPa.
15. Use of an abrasion-resistant laminated product obtained by the process according to any one of claims 1 to 7 or according to any one of claims 8 to 10 for the production of tipper bottoms for granular materials or floors or sprockets for conveyor systems or sprockets for bicycle or motorcycle or car, or conveyors or tracks for construction machinery or floor coverings or ship deck plates or railway track components or machine guard panels or lining for hoppers or chutes and bins or brake shoes.
16. Use of a laminated product obtained by the process according to any one of claims 1 to 5 or according to any one of claims 11 to 14 for the production of heat sinks such as structural parts which 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, refrigerated plates, squirrel cage rotors used especially in induction motors, roof coils.