Sheet metal for granular material skip

A controlled manufacturing process for 6xxx series aluminum alloy dumpsters addresses abrasion issues by enhancing durability and reducing costs, achieving effective abrasion resistance without relief patterns.

FR3151605A1Active Publication Date: 2025-01-31CONSTELLIUM ISSOIRE +1
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Patent Information

Application Number
FR2023008225
Authority / Receiving Office
FR · FR
Patent Type
Applications
Current Assignee / Owner
Filing Date
2023-07-28
Publication Date
2025-01-31
Estimated Expiration
2043-07-28

AI Technical Summary

Technical Problem

Existing aluminum alloy dumpsters for granular materials suffer from significant abrasion wear during unloading, particularly at the bottom, leading to high maintenance costs and material loss, and existing solutions like relief-patterned sheets are expensive or ineffective in preventing sliding retention.

Method used

A process for manufacturing an abrasion-resistant laminated aluminum alloy product using specific 6xxx series alloys, involving controlled hot rolling and cooling without solution/quenching, followed by optional cold rolling and heat treatment, to create a durable sheet for the dumpster bottom.

Benefits of technology

The process results in a cost-effective, lightweight aluminum dumpster with improved abrasion resistance, reducing material loss and maintenance costs without the need for relief patterns, maintaining mechanical integrity while ensuring effective granular material flow.

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Abstract

The invention relates to a method for manufacturing an abrasion-resistant rolled product made of 6XXX series aluminum alloy, wherein, after hot rolling and cooling to room temperature, the rolled aluminum alloy product is not subjected to a solution treatment / quenching process and is not embossed. The invention also relates to a granular material container comprising an abrasion-resistant rolled product obtained by the method according to the invention, and to the method for manufacturing such a container. The invention makes it possible to obtain an improved abrasion-resistant rolled aluminum alloy product with satisfactory mechanical properties for this application and an economical manufacturing process.
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Description

Title of the invention: Sheet metal for a skip for granular materials Field of invention

[0001] The invention relates to sheets for bins for granular materials which have improved abrasion resistance. State of the art

[0002] A skip for granular materials most often comprises a base, typically a flat or curved base 1, and a plurality of side walls 2, 4 intended to confine the granular material to be transported; typically, a skip has a rectangular shape and comprises two sets of side walls, at least one of which 2 can be opened to unload the granular material by tilting the skip using a jack 3 (see [Fig.l]). Another method of construction is the so-called "half-moon" shape comprising a curved base and side walls, of which the one which can be opened to unload the granular material can have a more or less complex curved shape. There are other shapes of skip, in particular those which allow unloading via the base. These skips may comprise, in addition to the base and the walls, external stiffeners or frames.The parts of the walls and bottom that come into contact with the granular material are usually smooth, so that the granular material slides well when unloading.

[0003] Bins for granular materials are typically unloaded by dumping: the bin is tilted, and the granular material flows out through an opening. This opening may be a side hatch. The flow may also be through an opening in the bottom of the bin. In all cases, during this flow, the granular material slides along the bottom of the bin. This leads to abrasion wear. This wear of the bottom of the bin is greater near the opening through which the bin is unloaded, because the pressure is higher there. The wear depends on the material used for the bottom of the bin and the granular material. It also depends on the tilting speed of the bin, as well as the rheological characteristics of the granular material.These rheological characteristics may depend, for example, on the humidity level: we know that dry sand flows as the bucket rises, while wet sand, which is more sensitive to compaction, flows in several blocks which detach from the main mass. The term "granular material" here includes any granular material, whatever its origin and nature, mineral or organic, which is usually transported in buckets, such as: sand, gravel, pebbles, stones, topsoil, backfill soil, seeds, etc.

[0004] The flow conditions encountered on steel skips lead to a Significant abrasion of the bottom of the skips. Several remedies have been proposed. The bottom of the skip can be covered with a rubber sheet or strip. More abrasion-resistant sheets have also been used, for example Hardox ® 400 or 500, these sheets typically exhibiting a weight loss of 200 to 300 mg after 4000 Taber test cycles. The geometry of the skip can also be optimized to minimize the pressure exerted by the granular material on the skip surfaces; the dumper-type skip is an example of such a geometry.

[0005] These products are quite expensive. Furthermore, we would like to have abrasion-resistant skips that can be made of aluminum alloy, because with equivalent performance, they are lighter than steel skips.

[0006] Patent application WO2006 / 035155 describes a skip for transporting, storing or handling granular material comprising a base and side walls, characterized in that at least part of the base comprises a sheet having been printed by rolling with one or more relief patterns on one face, said sheet being arranged so that during transport or during unloading of the granular material, said pattern is in contact with said granular material. The alloys used for the relief sheets can be steel or, preferably, an aluminum alloy, such as an alloy of the 5xxx series, the copper-free Al-Zn-Mg type alloys of the 7xxx series, such as 7020, and the alloys of the 6xxx series, such as 6061. The printed sheets, however, have two disadvantages: on the one hand, they are more expensive and on the other hand, the granular material is retained and only begins to slide with a high angle of incidence.

[0007] Patent application WO2018 / 104004 relates to a method for manufacturing an abrasion-resistant aluminum alloy rolled product comprising the steps of: (a) providing 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 remainder 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 wherein the exit temperature of the hot rolling mill is in a range of 130 to 285°C; (e) cooling the hot rolled material to room temperature.

[0008] The aim of the present invention is to propose an improved rolled product made of aluminium alloy, intended in particular for the production of skips for the transport of granular materials, resistant to abrasion, having satisfactory mechanical properties for this application and the manufacturing process of which is economical. Subject of the invention

[0009] A first object of the invention is a method of manufacturing an abrasion-resistant rolled product made of aluminum alloy, comprising the following successive steps: (a) casting a 6XXX series aluminium alloy into a rolling plate, (b) heating the rolling plate to a temperature of 450°C to 580°C, (c) hot rolling the thus heated rolling plate in one or more rolling stages to a sheet of intermediate thickness of 12 to 40 mm, preferably 15 to 30 mm, the inlet temperature of the hot rolling mill preferably being 450°C to 560°C and the outlet temperature of the hot rolling mill preferably being 380°C to 530°C, (d) hot rolling the intermediate thickness sheet in one or more rolling steps to a hot rolling exit thickness sheet of 3 mm to 15 mm, the temperature of the intermediate thickness sheet when step (d) starts being 330°C to 460°C, and the exit temperature of the hot rolling mill being 170°C to 320°C, (e) cooling the hot rolling outlet thickness sheet from the hot rolling mill outlet temperature to room temperature, (f) optionally cold rolling the hot rolling output thickness sheet with a reduction rate of 10% to 40% and / or carrying out heat treatment at a temperature of 150°C to 200°C, wherein, after hot rolling and cooling to room temperature, the rolled aluminum alloy product is not subjected to solution / quenching treatment and is not printed with a relief pattern.

[0010] A second subject of the invention is a method of manufacturing a bin for granular material in which an abrasion-resistant rolled product is obtained by the method according to the invention, said abrasion-resistant rolled product is shaped and / or assembled to form a bin for granular material comprising said abrasion-resistant rolled product.

[0011] A third object of the invention is a bin for granular material comprising an abrasion-resistant rolled product obtained by the method according to the invention.

[0012] A fourth object of the invention is the use of an abrasion-resistant rolled product obtained by the method according to the invention for manufacturing a container for granular material.

[0013] A fifth object of the invention is the use of a skip according to the invention for the transport of granular material. Description of figures

[0014] [Fig. 1] [Fig. 1] shows a bin for granular material made of sheets and profiles.

[0015] [Fig.2] [Fig.2] shows the relationship between the yield strength in the TL direction and the abrasion measured by the Taber test. Description of the invention

[0016] All aluminum alloys mentioned hereinafter are designated according to the rules and designations defined by The Aluminum Association in Registration Record Series which it publishes regularly, unless otherwise stated.

[0017] The metallurgical states referred to are designated according to European standard EN-515 (1993) unless otherwise stated.

[0018] All alloy compositions are provided in % by weight (wt%).

[0019] 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 standard NF EN ISO 6892-1 (2016), the location of gripping of the parts and their direction being defined in standard EN 485 (2016).

[0020] Unless otherwise stated, the definitions in EN 12258 (2012) apply.

[0021] The applicant has realized that it is possible to improve the wear resistance of the bottom of the skips by developing more abrasion-resistant alloys or materials from the 6XXX family, without increasing the manufacturing cost thanks to a process that does not include solution treatment and quenching after hot rolling. Contrary to what the person skilled in the art thought, the modification of the metallurgy resulted in a very significant improvement in abrasion resistance, without using alloys or materials that are unusual in the construction of industrial vehicles and / or much more expensive than the materials usually used and without using a relief sheet on the bottom of the skip.

[0022] The inventors have found that, surprisingly, alloy sheets of the 6XXX family which have not undergone solution treatment and quenching after hot rolling and which are not in the form of relief sheet, but whose processing conditions have been carefully chosen, have excellent abrasion resistance. According to standard EN 12258-1, the person skilled in the art understands by "relief sheet" a "sheet having been printed with a relief pattern on one face, by rolling".

[0023] According to the invention, the method for manufacturing an abrasion-resistant rolled product made of aluminum alloy comprises the successive steps of casting, heating, hot rolling to a sheet of intermediate thickness, hot rolling to a sheet of hot rolling outlet thickness and cooling to tem room temperature, optionally cold rolling and / or heat treatment at a temperature of 170°C to 320°C, but does not include solution treatment / quenching after hot rolling and is not printed with a relief pattern.

[0024] In a step (a), an aluminum alloy of the 6XXX series is cast in the form of a rolling plate.

[0025] Preferably the alloy of the 6XXX series has the composition, in % by weight, 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 aluminum.

[0026] The Si content is preferably at least 0.3 or 0.4% and / or at most 0.9% or 0.8%. In one embodiment the Si content is 0.4 to 0.8%. In one embodiment the Si content is 0.7 to 1.3%.

[0027] The Mg content is preferably at least 0.6 or 0.7% and / or at most 1.3%. or 1.2%. In one embodiment the Mg content is 0.8 to 1.2%.

[0028] The Fe content is preferably at most 0.6%. In one embodiment the Fe content is 0.3 to 0.7%. In one embodiment the Fe content is 0.1 to 0.5%.

[0029] The Cu content is preferably at most 0.8% or 0.7%. In one embodiment the Cu content is 0.1 to 0.4%. In one embodiment the Cu content is at most 0.2%.

[0030] The Mn content is preferably at most 0.9% or 0.8%. In one embodiment the Mn content is at most 0.2%. In one embodiment the Mn content is 0.4 to 1.0%.

[0031] The Cr content is preferably at most 0.35% or 0.30%. In one embodiment the Cr content is 0.05 to 0.25%.

[0032] The Zn content is preferably at most 0.30% or 0.25%. In one embodiment the Zn content is from 0.01 to 0.20%.

[0033] The Ti content is preferably at most 0.12% or 0.10%. In one embodiment the Ti content is 0.01 to 0.10%.

[0034] The other elements are unavoidable impurities, the maximum content of which for each is 0.05% and 0.15% in total.

[0035] In one embodiment, the alloy of the 6XXX series is chosen from the alloys AA6061, AA6063 and AA6082, as designated by The Aluminum Association.

[0036] The chosen composition makes it possible in particular to obtain improved abrasion resistance and satisfactory mechanical properties for producing skips and to use an economical manufacturing process, not requiring solution treatment after hot rolling.

[0037] In a step (b) the rolling plate is heated to a temperature of 450°C to 580°C. In one embodiment, the heating temperature of the rolling plate is at least 510°C, or is at least 520°C, or is at least 530°C, or is at least 540°C, or is at least 550°C, or is at least 560°C, and / or is at most 570°C, or is at most 560°C, or is at most 550°C, or is at most 540°C, or is at most 530°C, or is at most 520°C. In one embodiment, the heating is a homogenization, the duration of which is 4 to 48 hours. In one embodiment, the heating is a treatment making it possible to reach the hot rolling start temperature.

[0038] In a step (c) the rolling plate is hot rolled in one or more rolling steps to a sheet of intermediate thickness of 12 to 40 mm, preferably 15 to 30 mm, the inlet temperature of the hot rolling mill preferably being 450°C to 560°C and the outlet temperature of the hot rolling mill preferably being 380°C to 530°C.

[0039] In one embodiment, the inlet temperature of the hot rolling mill for the step(s) of rolling to an intermediate thickness sheet is at least 460°C, or is at least 470°C, or is at least 480°C, or is at least 490°C, or 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, or is at most 500°C, or is at most 490°C, or is at most 480°C, or is at most 470°C.

[0040] In one embodiment, the outlet temperature of the hot rolling mill for the step(s) of rolling to an intermediate thickness sheet is at least 390°C, or is at least 400°C, or is at least 410°C, or 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, or is at least 500°C, or is at least 510°C, and / or is at most 520°C, or is at most 510°C, or is at least 520°C. more than 500°C, or is at most 490°C, or is at most 480°C, or is at most 470°C, or is at more than 460°C, or is at most 450°C, or is at most 440°C, or is at most 430°C, or is at more than 420°C, or is at most 410°C, or is at most 400°C.

[0041] In a step (d) the intermediate thickness sheet is hot rolled in one or more rolling steps to a hot rolling exit thickness sheet of 3 mm to 15 mm, the temperature of the intermediate thickness sheet when step (d) begins being 330°C to 460°C and the exit temperature of the hot rolling mill being from 170°C to 320°C.

[0042] In one embodiment, the inlet temperature of the hot rolling mill for the rolling step(s) to a hot rolling exit thickness sheet is at least 340°C, or is at least 350°C, or is at least 360°C, or is at least 370°C, or is at least 380°C, or is at least 390°C, or is at least 400°C, or is at least 410°C, or is at least 420°C, or is at least 430°C, or is at least 440°C, and / or is at most 450°C, or is at most 440°C, or is at most 430°C, or is at most 420°C, or is at most 410°C, or is at most 400°C, or is at most 390°C, or is at most 380°C, or is at most 370°C, or is at most 360°C, or is at most 350°C.

[0043] In one embodiment, the outlet temperature of the hot rolling mill for the rolling step(s) to a hot rolling outlet thickness sheet is at least 180°C, or is at least 190°C, or is at least 200°C, or is at least 210°C, or is at least 220°C, or is at least 230°C, or is at least 240°C, or is at least 250°C, or is at least 260°C, or is at least 270°C, or is at least 280°C, or is at least 290°C, or is at least 300°C, and / or is at most 310°C, or is at most 300°C, or is at most 290°C, or is at most 280°C, or is at most 270°C, or is at most 260°C, or is at most 250°C, or is at most 240°C, or is at most 230°C, or is at most 220°C, or is at most 210°C, or is at most 200°C, or is at most 190°C.

[0044] In a step (e) the hot rolling outlet thickness sheet is cooled from the outlet temperature of the hot rolling mill to ambient temperature,

[0045] In an optional step (f), the hot rolling output thickness sheet is cold rolled with a reduction rate of 10% to 40% and / or a heat treatment is carried out at a temperature of 150°C to 200°C. In one embodiment of step (f), the reduction rate of the optional cold rolling step is at least 15%, or is at least 20%, or is at least 25%, or is at least 30%, and / or is at most 35%, or is at most 30%, or is at most 25%, or is at most 20%. In one embodiment of step (f) the reduction rate of the optional cold rolling step is at least 15%, or is at least 20%, or is at least 25%, or is at least 30%, and / or is at most 35%, or is at most 30%, or is at most 25%, or is 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 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.

[0046] According to the invention, after hot rolling and cooling to room temperature the rolled product made of aluminum alloy is not subjected to a solution treatment / quenching and is not printed with a relief pattern. If one or more optional steps of cold rolling and / or heat treatment at a temperature of 150 °C to 200 °C are carried out, the rolled product made of aluminum alloy is of course also not subjected to a solution treatment / quenching and is not printed with a relief pattern before or after these steps.

[0047] The abrasion-resistant product obtained by the process according to the invention is typically in a metallurgical state F, if it is not cold rolled, or H if it is cold rolled.

[0048] The surface of the abrasion-resistant rolled product according to the invention can be described as the rough rolling surface, whereby rolling lines are distinguished, parallel to the rolling direction, which correspond to peaks and valleys parallel to the rolling direction.

[0049] Surprisingly, although the abrasion-resistant rolled product according to the invention generally has a lower mechanical strength than products in a T state, cold-rolled and subjected to a solution treatment / quenching and tempering, its abrasion resistance is equivalent or slightly lower. The abrasion-resistant rolled product according to the invention also has a higher abrasion resistance than products made of 5XXX alloy according to the current state of the art.

[0050] Advantageously, the mass loss in mg under Taber test conditions of 60 rpm, number of revolutions 4,000 applied force 10N, room temperature, type of movement: rolling, friction radius: 31.75 mm (U = 200 mm), friction roller H-22, is less than 400 mg.

[0051] The invention also relates to a method for manufacturing a bin for granular material in which an abrasion-resistant rolled product is obtained by the method according to the invention and said abrasion-resistant rolled product is shaped and / or assembled to form a bin for granular material comprising said abrasion-resistant rolled product.

[0052] The invention also relates to a bin for granular material comprising an abrasion-resistant rolled product obtained by the method according to the invention.

[0053] According to the invention, the abrasion-resistant rolled product is arranged at the bottom of the bucket, so as to be in contact with the granular material when the bucket is loaded. The abrasion-resistant rolled product may be arranged over the entire surface of the bottom of the bucket, or only on the part which is close to the hatch through which the granular material is discharged. In the context of the present invention, the term "bottom" must be understood as meaning the part of the bucket on which the granular material exerts a downward force (when the bucket is in position horizontal (transport position), whereas the term "wall" should be understood as meaning the part of the bucket on which the granular material exerts a rather horizontal force. The bottom and the walls may be separate parts (assembled for example by welding or bolting), or represent a single curved shape (assembled or not). What matters is that at least part of the bottom of the bucket, namely the part on which the granular material slides during its unloading, is covered with abrasion-resistant laminated product according to the invention. In one embodiment, the bucket according to the invention is characterized in that the abrasion-resistant laminated product covers the entire surface of the bottom of the bucket, or only part of the surface of said bottom on which the granular material slides during its unloading.

[0054] In the following examples, advantageous embodiments of the invention are described by way of illustration. These examples are not limiting in nature. Example

[0055] In this example, the mechanical properties and abrasion resistance of alloy sheets according to the invention, obtained according to the method of the invention or not, were compared and compared with sheets according to the prior art made of alloy of the 5XXX series.

[0056] Table 1 discloses the composition of the alloys that were cast in the form of rolling slab, in % by weight.

[0057] [Table 1] - Chemical composition (% by weight) Alloy Si Fe Cu Mn Mg Cr Zn Ti A 0.7 0.4 0.3 0.0 1.0 0.2 0.15 0.01 B 0.6 0.1 0.3 0.1 1.0 0.2 0.01 C 0.1 0.2 0.0 0.8 4.8 0.1 0.01 D 0.1 0.2 0.0 0.8 4.9 0.1 0.01 E 0.1 0.3 0.1 0.5 4.4 0.1 0.01 F 0.1 0.1 0.0 0.9 4.7 0.1 0.01 0.01 G 0.9 0.3 0.1 0.5 0.8 0.01

[0058] The rolling plates were transformed by hot rolling and optionally by cold rolling. The transformation conditions are given in Table 2.

[0059] [Table 2] Transformation conditions Reference Alloy Heating having hot rolling i Hot rolling to a thickness mtennéÆaïrê Thickness mteiTnédidire (mm) Hot rolling to end thickness of hot filing End thickness of hot rolling (mmi Cold rolling Solution / quenching water Tempering T' entry m T' exit ro T entry CC) T' exit PC) Al A. 510 488 444 ■ 23.1' 434 272 6.3 - - A-2 A 510 488 444 23.1 454 -77 ? 6.3 10¾ - - A-3 A 51C 488 : 444 23.1. 434 2-2 6.3 20% ■ A-4. A 510 488 444 23.1 434 272 6.3 30 - - A-5 A 510 488 444 23.1 434 272 6.3 40% - - A-6 A 510 488 444 23.1 434 272 6.3 7555 211'65'0 211175^0 Bl B 510 494 420 22. ' 366 288 9.5 - 2h565'C 10E175aC Cl C 508 4S7 345 16.1 345 249 7.0 - - - Dl D 510 474 418 15.3 418 249 w - ■ ■ El E 5.1 ​​■ - - Kl '.F 25.4 - - - Gl G 530 465: 430 21.3 430 "274 5.3

[0060] The mechanical properties of the obtained sheets were characterized. The results are provided in Table 3.

[0061] [Table 3] - Mechanical properties Reference Rp0j2 TL(MPa) RmTL(MPa) A% TL HB Hardness Al 130 162 21 46 A-2 164 178 12 A-3 183 195 9 A-4 188 201 8 A-5 201 214 7 A-6 384 409 4 127 Bl 279 318 16 104 Cl 233 360 20 98 Dl 244 357 19 99 El 235 344 19.3 94 Fl 285 336 9.6 104 Gl 130 144 21

[0062] In an abrasion resistance test, the samples were tested using a standardized setup according to Taber 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, which means that the abrasion of the material takes place transversely. The weight loss is measured after 4000 revolutions and is called number of cycles (revolutions) as mass loss per revolution (mg / revolution). The applied test parameters were: 60 revolutions / min, number of revolutions 4000 (resulting in a sliding path of 800 m), applied force 10 N, room temperature, type of motion: rolling, friction radius: 31.75 mm (U = 200 mm), friction roller H-22, for each test series new friction rollers were used. The results are shown in Table 4

[0063] [Table 4] - Taber test results Reference Mass loss for 4000 cycles (mg) Mass loss / cycle (mg / cycle) Al 361 0.09 A-2 A-3 A-4 A-5 368 0.09 A-6 298 0.07 Bl 228 0.06 Cl 715 0.18 Dl 479 0.12 El 521 0.13 Fl 527 0.13 Gl

[0064] The relationship between the elastic limit and the mass loss during the Taber test is given in [Fig.2]. The samples according to the invention, A1 and A-5, show after 4000 cycles a mass loss of less than 400 mg despite a mechanical resistance lower than that of the other samples.

Claims

Claims

1. A method of manufacturing an abrasion-resistant rolled product of aluminum alloy, comprising the following successive steps: (a) casting a 6XXX series aluminum alloy into a rolling plate, (b) heating the rolling plate to a temperature of 450°C to 580°C, (c) hot rolling the thus heated rolling plate in one or more rolling stages to a sheet of intermediate thickness of 12 to 40 mm, preferably 15 to 30 mm, the inlet temperature of the hot rolling mill preferably being 450°C to 560°C and the outlet temperature of the hot rolling mill preferably being 380°C to 530°C, (d) hot rolling the intermediate thickness sheet in one or more rolling steps to a hot rolling exit thickness sheet of 3 mm to 15 mm, the temperature of the intermediate thickness sheet when step (d) starts being 330°C to 460°C, and the exit temperature of the hot rolling mill being 170°C to 320°C, (e) cooling the hot rolling exit thickness sheet from the exit temperature of the hot rolling mill to room temperature, (f) optionally cold rolling the hot rolling exit thickness sheet with a reduction ratio of 10% to 40% and / or performing a heat treatment at a temperature of 150°C to 200°C, wherein, after hot rolling and cooling to room temperature, the aluminum alloy rolled product is not subjected to a heat treatment solution / dip and is not printed with a raised pattern.

2. A method according to claim 1 wherein the 6XXX series alloy has the composition, in wt%, of 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 aluminum.

3. A method according to claim 1 or claim 2 wherein the 6XXX series alloy is selected from AA6061, AA6063 and AA6082 alloys, as designated by The Aluminum Association.

4. A method of manufacturing a granular material bin in which an abrasion-resistant rolled product is obtained by the method according to any one of claims 1 to 3, said abrasion-resistant rolled product is shaped and / or assembled to form a granular material bin comprising said abrasion-resistant rolled product.

5. A bin for granular material comprising an abrasion-resistant rolled product obtained by the method according to any one of claims 1 to 3.

6. A skip according to claim 5, characterized in that the abrasion-resistant laminated product covers the entire surface of the bottom of the skip or only a part of the surface of said bottom on which the granular material slides during its unloading.

7. Use of an abrasion-resistant rolled product obtained by the method according to any one of claims 1 to 3 for manufacturing a bin for granular material.

8. Use of a skip according to any one of claims 5 to 6 for the transport of granular material.

Citation Information

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