Method for manufacturing a sheet or plate of high strength aluminum alloy and article including an aluminum alloy produced using the method for manufacturing the sheet or plate of high strength aluminum alloy

Abstract

A method for producing a sheet or plate of aluminum alloy comprising the steps of: casting the alloy, the alloy having a composition including the following elements and percentage by weight: 6.80 – 10.00% Zn, 2.20 – 3.50% Mg, 1.30 – 4.00% Cu, 0.01 – 0.30% Sc, 0.05 – 0.20% Zr; cold rolling of the aluminum alloy sheet or plate at room temperature with a reduction per pass of between about 5% and 20%; applying a solution heat treatment to the sheet or plate by heating the sheet or plate to a temperature of between about 400°C and 500°C; quenching the sheet or plate; and performing an artificial ageing treatment by heating the sheet or plate to a temperature of between about 80°C and 200°C and maintaining the sheet or plate at this temperature for a time period of between about 30 minutes and 100 hours.

Description

METHOD FOR MANUFACTURING A SHEET OR PLATE OF HIGH STRENGTH ALUMINUM ALLOY AND ARTICLE INCLUDING AN ALUMINUM ALLOY PRODUCED USING THE METHOD FOR MANUFACTURING THE SHEET OR PLATE OF HIGH STRENGTH ALUMINUM ALLOYTECHNICAL FIELD OF THE INVENTION

[0001] The present invention relates to the production of high-strength aluminum alloys. More particularly, it relates to a method for producing a sheet or plate of high-strength aluminum alloy and to high performance articles and products, such as, for example and without being limitative, sport equipment, aircraft components, or the like, including an aluminum alloy manufactured using the method for producing the sheet or plate of high-strength aluminum alloy, which is especially well adapted for use in these products.BACKGROUND

[0002] It is known in the art to add zinc (Zn) and magnesium (Mg) in an aluminum alloy, to produce a high-strength aluminum. Such a combination is referred to in the art as aluminum alloys of the 7000 series. Within this series, it is also known to add additional elements to further increase the desired characteristics of the alloy. Amongst those additional elements, the most popular elements added to this aluminum series are copper (Cu) and zirconium (Zr).

[0003] One of the best aluminum alloys of the 7000 series with added copper (Cu) and zirconium (Zr) is the 7068 aluminum alloy, which is known to have a yield strength of about 600MPa of and tensile strength of about 650MPa. The composition of this alloy is as follows:Element 7068 (wt. %)Zn 7.3 - 8.3 Mg 2.2 - 3.0 Cu 1.6 - 2.4 Zr 0.05 - 0.15 Fe 0.15 max Si 0.12 max Mn 0.1 max Ti 0.1 maxCr 0.05 max

[0004] In the case of the 7068 aluminum alloys, the combination of the optimized alloying elements concentrations and specific thermomechanical sequence used for production, results in an optimized aluminum alloy for high resistance. In view of the above, 7068 aluminum alloys are often used in the aerospace industry, medical devices, high-end sport equipment, the automotive industry and the like which require components with a high yield strength and / or tensile strength. Drawbacks of such high-strength alloys however commonly include relatively low elongation at break, limited stress corrosion cracking resistance, limited thermal stability and / or poor weldability.

[0005] In general, 7000 series alloys are widely used in the manufacture of sports equipment or other type of components requiring a good balance between being lightweight while offering high performance characteristics, such as stiffness, durability, strength or the like. For example, this is the case for high-performance stiff alpine skis for expert and advanced skiers, which can include reinforcements of modern high-strength aluminum alloys order to increase the rigidity, minimize vibration, etc. This is also the case for aircraft components or other types of components where weight is an important aspect.

[0006] Other doping elements can be added to an aluminum alloy in order to increase its mechanical properties. One of these non-standard doping elements is scandium (Sc). When added to an aluminum alloy, this element greatly increases the strength by promoting a smaller, even-sized grain structure in alloys during solidification and by forming fine aluminum-scandium precipitates. However, because scandium is expensive, it is commonly only used in alloys for most demanding applications and products. Hence, the commercial introduction of scandium in wide-spread applications and products has so far been limited.

[0007] The increase in strength from the addition of a small concentration of scandium is greater in some aluminum series than others. For example, the 5000 series aluminum alloy shows a great strength response from the addition of small quantities of scandium, but even with scandium, the yield strength of these alloys does not surpass the yield strength of the 7000 series. The 7000 series aluminum alloy also shows a strength response from the addition of small quantities ofscandium, but for some applications such as high-end sport equipment, aerospace, automotive industry or the like, there is still a need for greater increase in mechanical properties, such as strength, than what is currently known in the art.

[0008] In view of the above, there is a need for an improved method for manufacturing high strength aluminum alloy especially in sheet or plates, as well as article or components using the manufactured high strength aluminum alloy which, by virtue of its design and components, would be able to overcome or at least minimize some of the above-discussed prior art concerns.SUMMARY OF THE INVENTION

[0009] In accordance with a first general aspect, there is provided a method for producing a sheet or plate of aluminum alloy. The method comprises the steps of: casting the alloy, the alloy having a composition including the following elements in the specified range in percentage by weight: 6.80 - 10.00% Zn, 2.20 - 3.50% Mg, 1.30 - 4.00% Cu, 0.01 - 0.30% Sc, 0.05 - 0.20% Zr; cold rolling of the aluminum alloy sheet or plate, this step being performed at room temperature with a reduction rate of between about 5% and about 20% per pass;applying a solution heat treatment to the sheet or plate of aluminum alloy, this step being performed by heating the sheet or plate of aluminum alloy to a temperature of between about 400 °C and about 500 °C; quenching the sheet or plate of aluminum alloy; and performing an artificial ageing treatment, this step being performed by heating the sheet or plate of aluminum alloy to a temperature of between about 80 °C and about 200 °C and maintaining the sheet or plate of aluminum alloy at this temperature for a time period of between about 30 minutes and about 100 hours.

[0010] In an embodiment, the step of cold rolling of the aluminum alloy sheet or plate allows a reduction between about 20 % and about 95% of the thickness of the ingot.

[0011] In an embodiment, the step of cold rolling of the aluminum alloy sheet or plate allows a reduction between about 50 % and about 95% of the thickness of the ingot.

[0012] In an embodiment, the method further comprises the step of homogenizing the alloy ingot, this step being performed at a maximum temperature of between about 400 °C and about 500 °C.

[0013] In an embodiment, the step of homogenizing the alloy ingot is performed for a time period of between about 4 hours and about 26.5 hours.

[0014] In an embodiment, the step of homogenizing the alloy ingot includes performing hot isostatic pressing of the ingot, this step being performed at a temperature of between about 300 °C and about 500 °C, for a time period of between about 1 hour to 5 hours, while an isostatic pressure of between about 10 000 psi and about 20 000 psi, is applied simultaneously on the ingot.

[0015] In an embodiment, the method further comprises performing hot rolling of the previously homogenized aluminum alloy ingot, this step being performed at a temperature of between about 400 °C and about 500 °C, with a reduction rate of between about 5% and about 20% per pass and prior to the step of cold rolling of the aluminum alloy sheet or plate.

[0016] In an embodiment, the method further comprises fully annealing the previously hot rolled aluminum alloy sheet or plate, this step being performed at a temperature of between about 365 °C and about 465 °C, for a time period of between about 15 minutes and 5 hours.

[0017] In an embodiment, a step of cooling of the aluminum alloy sheet or plate at a rate of about 30°C / h until a temperature of the aluminum alloy sheet or plate of about 260°C is reached is provided following the step of fully annealing the previously hot rolled aluminum alloy sheet or plate.

[0018] In an embodiment, the method includes performing at least one intermediate partial annealing of the aluminum alloy sheet or plate, between passes of the cold rolling of the aluminum alloy sheet or plate.

[0019] In an embodiment, the intermediate partial annealing is performed at a temperature of between about 200 °C and about 500 °C, for a time period of between about 1 minute and 4 hours.

[0020] In an embodiment, the method further includes stretching of the sheet or plate of aluminum alloy before the step of performing the artificial ageing treatment.

[0021] In accordance with another general aspect, there is provided a sliding device including at least one sheet or plate of aluminum alloy manufactured using the method for producing a sheet or plate of aluminum alloy as described herein.

[0022] In an embodiment, the sliding device includes a core with the at least one sheet or plate of aluminum alloy being laminated to the core.

[0023] In accordance with another general aspect there is provided a sporting article comprising an aluminum alloy, the aluminum alloy being manufactured using the method for producing a sheet or plate of aluminum as described herein.

[0024] In accordance with another general aspect there is provided an aerospace article or component comprising an aluminum alloy, the aluminum alloy being manufactured using the method for producing a sheet or plate of aluminum alloy as described herein.

[0025] In accordance with another general aspect there is provided a use of an aluminum alloy being manufactured using the method for producing a sheet or plate of aluminum alloy as described herein in the manufacture of an article or component.

[0026] In an embodiment, the article or component is at least one of a sporting article or component, an aerospace article or component, a medical device article or component and a transport vehicle article or component.BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Other objects, advantages and features will become more apparent upon reading the following non-restrictive description of embodiments thereof, given for the purpose of exemplification only, with reference to the accompanying drawings in which:

[0028] Figure 1 is a flowchart showing the steps of the method for manufacturing a sheet or plate of high strength aluminum alloy in accordance with an embodiment.

[0029] Figure 2 is a metallographic image of the structure of a 7068 aluminum alloy.

[0030] Figure 3 is a metallographic image of the structure of an aluminum alloy produced using the method for manufacturing a sheet or plate of high strength aluminum alloy described herein.DETAILED DESCRIPTION

[0031] In the following description, the same numerical references refer to similar elements. The embodiments, configurations, materials mentioned and / or dimensions shown in the figures or described in the present description are embodiments only, given solely for exemplification purposes.

[0032] Moreover, although method for manufacturing high strength aluminum alloy and article using same includes steps as explained and illustrated herein, not all of these steps are necessarily essential and thus should not be taken in their restrictive sense. It will be appreciated that the steps of the method for manufacturing high strength aluminum alloy and for manufacturing article using same described herein may be performed in the described order, or in any suitable order.

[0033] To provide a more concise description, some of the quantitative and qualitative expressions given herein may be qualified with the terms "about", approximately, "substantially" and the like. It is understood that whether the terms "about", approximately, "substantially" and the likes are used explicitly or not, every quantity or qualification given herein is meant to refer to an actual given value or qualification, and it is also meant to refer to the approximation to such given value or qualification that would reasonably be inferred based on the ordinary skill in the art, including approximations due to the experimental and / or measurement conditions for such given value.

[0034] Especially, for the description of alloy compositions that follow, all references are to weight percentages (wt %) unless otherwise indicated. When referring to any numerical range of values, such ranges are to be understood to include each and every number and / or fraction between the stated range minimum and maximum. A range of about 0.001 to 0.1 wt % of an element, for example, would include all intermediate values between the lower and higher stated values, along with any intermediate value therebetween.

[0035] In the course of the present description, the term “substantially free” is understood to mean having no significant composition. One skilled in the art will however understand that trace amounts of incidental elements and / or impurities can find their way into a desired end product, with the product still being substantially free of the corresponding element.

[0036] The terms “a”, “an” and “one” are defined herein to mean “at least one”, that is, these terms do not exclude a plural number of items, unless stated otherwise.

[0037] With reference to Figure 1 , in accordance with one embodiment, there is provided a method 100 for manufacturing high-strength aluminum (Al) - magnesium (Mg) - zinc (Zn) - copper (Cu) alloy having additions of scandium (Sc). More particularly, as will be described in more details below, the method is used for manufacturing sheet or plates of the Al-Mg-Zn-Cu alloy having additions of scandium (Sc). The method of manufacturing the alloy as described herein includes a combination of the steps of the process for the manufacture of the sheet or plates of alloy and the associated specific alloy composition used. As will be described in more details below, the combination of the process for the manufacture of the alloy and the specific alloy composition described below allows the method of manufacture to produce a sheet or plate of an aluminum-scandium alloy having advantageous mechanical properties, over know prior art alloys.

[0038] More specifically, in an embodiment, the present Al-Mg-Zn-Cu alloy having additions of scandium (Sc) is characterized by a high yield / tensile strength and ductility. Furthermore, in an embodiment, the present manufactured Al-Mg-Zn- Cu alloy having additions of scandium (Sc) offers at least one of an increased weldability, fracture toughness, thermal stability and corrosion resistance.

[0039] In an embodiment, the present Al-Mg-Zn-Cu alloy having additions of scandium (Sc) can include between about 0.01 % and about 1 % of scandium (Sc). However, as will be described in more details below, given the high price of scandium (Sc), in some embodiments, the quantity of scandium (Sc) in the alloy is balanced to produce an alloy having the desired increased mechanical properties (e.g. the desired increase in yield strength and / or tensile strength) while minimizing the costs thereof. Therefore, in an embodiment the present Al-Mg-Zn-Cu alloy having additions of scandium (Sc) can include up to 0.3% of scandium (Sc).

[0040] In an embodiment, the present aluminum-scandium alloy can include aluminum (Al) produced by electrolysis using inert anode or other industrial process that produce aluminum (Al) with oxygen byproducts, such as the aluminum produced using the processed used by Elysis™.

[0041] In an embodiment, the present aluminum-scandium alloy can also include scandium (Sc) extracted from spent acid of titania slag upgrading using ionexchange resins, such as the scandium (Sc) produced using the proprietary process from Element North 21™, to produce high purity scandium oxide from titanium production byproducts.

[0042] The method 100 for manufacturing the high-strength aluminum- scandium alloy includes an initial step 110 of casting the alloy. During this step, the constituent elements of the aluminum-scandium alloy are melted and subsequently casted in ingots for subsequent processing. In the course of the description below, reference to a single ingot will be made, thereby describing the steps being applied to form a sheet or plate of the high-strength aluminum-scandium alloy following casting of an ingot. One skilled in the art will understand that, in an embodiment, a plurality of ingots could be processed using similar steps to produce a plurality of sheet or plates of the high-strength aluminum-scandium alloy.

[0043] In an embodiment, the constituent elements of the aluminum-scandium alloy are melted to a temperature of 650 °C. In an alternative embodiment the constituent elements of the aluminum-scandium alloy can be melted to a temperature of 710 °C.

[0044] In an embodiment, referring to Table I, the working range for each one of the main alloying elements used in the present alloy are shown below:Table IElement Concentration (wt. %)Zn 6.80 - 10.0Mg 2.20 - 3.50Cu 1.30 - 4.00Sc 0.01 - 0.30Zr 0.05 - 0.020Fe 0.00 - 0.03Si 0.00 - 0.15Mn 0.00 - 0.10Ti 0.00 - 0.10Cr 0.00 - 0.10Al Remainder

[0045] As mentioned above, in alternative embodiments, higher quantity of scandium (Sc) can be used in the alloy. For example and without being limitative, in an embodiment, the quantity of scandium (Sc) can be between about 0.01 % and about 1 %. It will be understood that, over a quantity of about 0.3% of scandium (Sc), the price of the alloy is considerably augmented. However, in applications where the needs justify high-cost alloys, such quantity of scandium can be desirable.

[0046] The above-mentioned range of quantity for the doping elements in the present alloy are specifically dedicated to provide a targeted alloy structure with the above-mentioned advantageous mechanical properties such as, for example and without being limitative, the increased yield / tensile strength, ductility, weldability, thermal stability and / or corrosion resistance.

[0047] For example and without being limitative, the zinc (Zn) and magnesium (Mg) provided in the above-mentioned range of quantity is dedicated to form a secondary separation of the strengthening phases (MgZn2) due to dispersion hardening, with lower amounts negatively impacting the yield / tensile strength of the alloy and higher amounts negatively impacting the ductility of the alloy.

[0048] Moreover, the copper (Cu) provided in the above-mentioned range of quantity is dedicated to further increase the strength of the alloy by forming fine precipitates during artificial ageing which will be described in more details below. In an embodiment, the copper (Cu) provided in the above-mentioned range of quantity can also refine the micro structure of the material, leading to smaller and more uniformly distributed primary and secondary phase particles, which can lead to improved mechanical properties such as higher strength, better fatigue resistance, and improved toughness. It will be understood that, at lower concentrations, the strengthening will no longer be sufficient to increase the alloy strength. Conversely, higher amounts of copper (Cu) in aluminum-scandium alloys can lead to a decreased ductility, stress-corrosion cracking resistance and hot tear resistance, or to an increase of brittleness of the alloy.

[0049] Furthermore, the scandium (Sc) and zirconium (Zr) provided in the above-mentioned range of quantity are dedicated to increasing the yield / tensile strength of the alloy, with lower amounts negatively impacting the yield / tensile strength of the alloy and higher amounts greatly impacting on the price of the resulting alloy and even being susceptible to adversely affecting some of the mechanical properties of the alloy.

[0050] Still referring to Figure 1 , in the embodiment shown, the method 100 for manufacturing the high-strength aluminum-scandium alloy also includes a step 120 of homogenizing the alloy ingot at a high temperature. In an embodiment, the step of homogenizing the alloy ingot can be performed for a time period of between about 4 hours and about 26.5 hours, at a maximum temperature of between about 400 °C and about 500°C. In other words, during this manufacturing step, the aluminum- scandium alloy ingot is subjected to heating at a temperature within the above- mentioned range, for a time period also being within the above-mentioned range. For example and without being limitative, more specifically, in an embodiment, the step of homogenizing the aluminum-scandium alloy ingot can be performed for a time period of about 26.5 hours, at a temperature of about 465 °C. In an embodiment, this step can be omitted. One skilled in the art will understand that the length of the period of time can vary depending on the size of the alloy ingot. For example and without being limitative, in embodiments where the alloy ingot is of a bigger size, thestep of homogenizing the alloy ingot can be performed for a time period over 26.5 hours.

[0051] In an embodiment, a further step of the step 120 of homogenizing the aluminum-scandium alloy ingot can further include performing hot isostatic pressing of the ingot, to improve the density and remove remaining porosity thereof. In an embodiment, this step is performed by applying isostatic pressure onto a heated ingot. In an embodiment, the isostatic pressing of the ingot can be performed at a temperature of between about 300 °C and about 500 °C, for a time period of between about 1 hour to 5 hours, while an isostatic pressure of between about 10 000 psi and about 20 000 psi, is applied simultaneously on the ingot. More specifically, in an embodiment, the hot isostatic pressing of the ingot can be performed by subjecting the ingot to a temperature of about 350°C, while an isostatic pressure of about 14 000 psi is being applied simultaneously on the ingot, for a time period of about 2 hours. In an embodiment, this step can however be omitted.

[0052] Still referring to Figure 1 , in the embodiment shown, the method 100 for manufacturing the sheet or plate of high-strength aluminum alloy includes a subsequent step 130 of performing hot rolling of the previously homogenized aluminum alloy ingot. In an embodiment, the hot rolling of the previously homogenized aluminum alloy ingot is performed at a temperature of between about 400 °C and about 500 °C, with a reduction rate of between about 5% and about 20% per pass. In an embodiment, a different reduction rates can be applied during a first portion of the hot rolling and during a second portion of the hot rolling. For example and without being limitative, in an embodiment a first reduction rate can be applied during the first portion of the hot rolling and a second reduction rate can be applied during the second portion of the hot rolling.

[0053] In an embodiment, the hot rolling step can be performed until a remaining thickness of the ingot requires a reduction of between about 20 % and about 95% of the thickness of the ingot before reaching the final thickness (i.e. the subsequent step of cold rolling, which will be described in more details below, provides a reduction of between about 20 % and about 95% of the thickness of the ingot between the end of the hot rolling step and the final thickness).

[0054] In an alternative embodiment, the hot rolling step can be performed until a remaining thickness of the ingot requires a reduction of between about 50 % and about 95% of the thickness of the ingot before reaching the final thickness (i.e. the subsequent step of cold rolling, which will be described in more details below, provides a reduction of between about 50 % and about 95% of the thickness of the ingot between the end of the hot rolling step and the final thickness).

[0055] In an embodiment, the step of hot rolling of the previously homogenized aluminum alloy ingot can be omitted.

[0056] In an embodiment, the present method of manufacture of the sheet or plate of aluminum alloy includes a step 140 of fully annealing the previously hot rolled aluminum alloy sheet or plate. In an embodiment, the step of fully annealing the aluminum alloy sheet or plate can be performed at a temperature of between about 365 °C and about 465 °C, for a time period of between about 15 minutes and 5 hours. Moreover, in an embodiment, this step includes a subsequent cooling of the aluminum alloy sheet or plate at a rate of about 30°C / h until a temperature of the aluminum alloy sheet or plate of about 260°C is reached. In an embodiment, this step of fully annealing the previously hot rolled aluminum alloy sheet or plate can be omitted.

[0057] In an embodiment, the present method 100 of manufacture of the aluminum alloy sheet or plate includes a further step 150 of cold rolling of the aluminum alloy sheet or plate to further reduce the material's thickness and improve surface finish. In an embodiment, the cold rolling of the aluminum alloy sheet or plate is performed at room temperature with a reduction rate of between about 5% and about 20% per pass.

[0058] In an embodiment, the step of cold rolling of the aluminum alloy sheet or plate allows a reduction of between about 20 % and about 95% of the thickness of the ingot. In an embodiment where a step of hot rolling is provided, the step of cold rolling of the aluminum alloy sheet or plate can therefore allow a reduction of between about 20 % and about 95% of the thickness of the ingot from the thickness of the ingot at the end of the step of hot rolling of the ingot and the final thickness.

[0059] In an alternative embodiment, the step of cold rolling of the aluminum alloy sheet or plate allows a reduction of between about 50% and about 95% of the thickness of the ingot. In an embodiment where a step of hot rolling is provided, the step of cold rolling of the aluminum alloy sheet or plate can therefore allow a reduction of between about 50% and about 95% of the thickness of the ingot from the thickness of the ingot at the end of the step of hot rolling of the ingot and the final thickness.

[0060] In an embodiment, the method 100 includes performing at least one intermediate partial annealing of the aluminum alloy sheet or plate, between passes of the previously mentioned cold rolling of the aluminum alloy sheet or plate. In an embodiment, the intermediate partial annealing of the aluminum alloy sheet or plate can be performed at a temperature of between about 200 °C and about 500 °C, for a time period of between about 1 minute and 4 hours. In an embodiment, each partial annealing is performed at a temperature of about 350 °C for a time period of about 30 minutes. In an embodiment, this step of performing at least one intermediate partial annealing of the aluminum alloy sheet or plate can be omitted.

[0061] In an embodiment, the present method 100 of manufacture of the aluminum alloy sheet or plate includes a further step 160 of performing a solution heat treatment to the sheet or plate of aluminum alloy, to dissolve any second-phase particles or solute clusters formed during previous processing. In an embodiment, during this step, the sheet or plate of aluminum alloy is heated to a temperature of between about 400 °C and about 500 °C and is maintained at this temperature for a corresponding time period. In an embodiment, the step of performing a solution heat treatment includes heating the aluminum alloy is at a temperature of about 460 °C and maintaining the sheet or plate of aluminum alloy at this temperature for a time period of about 30 minutes. One skilled in the art will understand that the length of the time period for which the sheet pr plate is maintained at the above-mentioned temperatures depends on the thickness of the sheet or plate, thicker sheets or plates requiring linger time periods.

[0062] Still referring to Figure 1 , in an embodiment, the present method 100 of manufacture of the aluminum alloy sheet or plate includes quenching 170 of thesheet or plate of aluminum alloy to prevent unwanted precipitates. In an embodiment, quenching of the aluminum alloy sheet or plate can be performed by water quenching thereof.

[0063] In an embodiment a step of stretching of the of the aluminum alloy sheet or plate can be performed to allow mechanical stress relief and straightening of the sheet or plate. For example and without being imitative, in an embodiment, the stretching can be performed to stretch the aluminum alloy sheet or plate of between about 1 % and about 3 %. In an embodiment, this step can be omitted.

[0064] Finally, in an embodiment a further step 180 of subjecting the aluminum alloy sheet or plate to an artificial ageing treatment can be provided, to promote the formation of desirable precipitates. In an embodiment, during this step, the sheet or plate of aluminum alloy is heated to a temperature of between about 80 °C and about 200 °C and is maintained at this temperature for a time period of between about 30 minutes and about 100 hours. For example and without being limitative, in an embodiment, the artificial ageing treatment includes heating the sheet or plate of aluminum alloy to a temperature of about 120 °C and maintaining the sheet or plate of aluminum alloy at this temperature for a time period of about 18 hours. In another alternative embodiment, the artificial ageing treatment includes heating the sheet or plate of aluminum alloy to a temperature of about 120 °C and maintaining the sheet or plate of aluminum alloy at this temperature for a time period of about 24 hours.

[0065] The technical effect obtained by using the above-described method 100 of manufacture of the sheet or plate of aluminum alloy having the above-described elements in the mentioned ranges includes enhancing strength properties and / or reducing the weight of the articles made of the alloy resulted from the addition of scandium. In an embodiment, the increase in yield strength and mechanical properties of the alloy results from the precipitation of AbSc and the refinement of the grain size by the presence of disperse secondary particles of AbSc, that also inhibit recrystallization to a certain extent during thermomechanical processing, as can be clearly seen from the images of Figures 2 and 3 where the structure of a 7068 alminum alloy (Figure 2) is compared to the structure of an aluminum alloy producedusing the method for manufacturing a sheet or plate of high strength aluminum alloy described herein (Figure 3).

[0066] Given that bonding aluminum sheet or plates with other flexible materials is often challenging, to improve the adhesion of aluminum sheet or plates, in an embodiment, a surface treatment can be applied to the sheet or plate of aluminum alloy. One skilled in the art will understand that such surface treatment will affect the surface layer of the sheet or plate of aluminum alloy to improve mechanical and / or chemical bonding with compatible adhesives. For example and without being limitative, in an embodiment, a surface treatment of phosphoric anodization can be applied. One skilled in the art will understand that other surface treatment can also be used.Working examplesShown below are working examples of aluminum alloys prepared using the abovedescribed method for manufacturing aluminum alloy sheet or plates and the associated measured mechanical property values of measured yield strength and tensile strength, which show the increase of mechanical values over prior art aluminum alloys.Example 1

[0067] In a first working example, three alloys were prepared using the abovedescribed method for manufacturing aluminum alloy sheet or plates. The composition of the alloys, including values associates to each one of the main alloying elements used in the present alloys are listed in table II below. One skilled in the art will understand that the alloys are substantially free of additional alloying elements not mentioned in table II below.Table IIAlloy Zn Mg Cu Sc Zr Fe Si Mn Ti Cr Al#1 8.3 3 1.6 0.05 0.15 0.15 0.12 0.1 0.1 0.05 Remainder#2 8.3 3 1.6 0.1 0.15 0.15 0.12 0.1 0.1 0.05 Remainder#3 8.3 3 1.6 0.2 0.15 0.15 0.12 0.1 0.1 0.05 Remainder

[0068] The mechanical properties of interest of each one of the alloys (#1 , #2, #3) of this working example and generated using the above-described method for manufacturing aluminum alloy sheet or plates are listed in Table III below.Table IIIYield strength UlitmateAlloy (Offset = 0.2%) tensile#1 560 625#2 611 662#3 637 692

[0069] As can be seen by the results shown in Table III, the strength of the alloy increases with the increase in quantity of scandium (Sc). The comparison of these alloys doesn’t show an optimal scandium concentration. However, given the price of scandium, the price of these alloys is sensitive to the concentrations of scandium. As mentioned above, for this reason, in an embodiment the concentration of scandium should remain between 0.01 % and 1 %.Example 2

[0070] In a second working example, another alloy was prepared using the above-described method for manufacturing aluminum alloy sheet or plates. The composition of the alloy, including values associated to each one of the main alloying elements used in the present alloy are listed in table IV below. One skilled in the art will understand that the alloy is substantially free of additional alloying elements not mentioned in table IV below.Table IVElement Concentration (wt. %)Zn 8.5 Mg 2.9 Cu 1.8 Sc 0.2 Zr 0.10 Fe 0.14 Si 0.068Mn 0.005Ti 0.02Cr 0.05 max> Al Remainder

[0071] The mechanical properties of this alloy were measured over 10 samples. The mean of the mechanical properties of this alloy are presented in TableV below.Table VYield strength Ulitmate(Offset = 0.2%) tensile Elongation at(MPa) strength (MPa) break (%)710 749 8.2>

[0072] As can be seen, the alloy produced in this working example further shows the potential of scandium additions in aluminum when further combined with the proposed steps of the process for the manufacture of the alloy. In this working example, the measured mechanical properties show that the mechanical strength of the alloy was further increased to 710 MPa while keeping high ductility with an elongation at break of 8.2%.Use of the aluminum alloy manufactured using the method of manufacture described above

[0073] In view of the above results showing that the proposed method of manufacture of a sheet or plate of aluminum alloy results in a product having increased mechanical properties, such as increased mechanical strength, one skilled in the art will understand that the manufacture of articles or components using the manufactured aluminum alloy would consequently result in articles or components offering advantageous characteristics.

[0074] In view of the above, one skilled in the art will therefore understand that the present description extends to the manufacture of articles, components or the likes produced using the aluminum alloy manufactured using the above-described method of manufacture.

[0075] One skilled in the art will understand that, as mentioned above, sporting articles requiring a good balance between being lightweight while offering high performance characteristics, such as stiffness, durability, strength or the like are especially well suited for being manufactured using the sheet or plate of aluminum alloy produced using the above-described method of manufacture.

[0076] Again, this includes alpine skis produced using alloy reinforcements in order to, amongst others, increase the rigidity of the skis. For example and without being limitative, in an embodiment, alpine skis can be manufactured using a core made of wood or material offering the desired flexibility, stiffness, etc. In an embodiment a sheet or plate of the aluminum alloy produced using the abovedescribed method of manufacture can be laminated to the core to extend along at least a section of the core (alone or in combination with a sheet or plate of composite material), in order to provide the desired mechanical properties of the resulting alpine ski. One skilled in the art will understand that, in alternative embodiments, other sliding devices such as, for example and without being limitative, snowboards, crosscountry skis or the like could also be manufactured with a core having a laminated sheet or plate of the aluminum alloy produced using the above-described method of manufacture extending along at least a section thereof. In alternative embodiments, the sheet or plate of aluminum alloy produced using the above-described method of manufacture could also be used as a top sheet or plate of the sliding device, for vertical strips along the sliding device or a section thereof, in the production of a binding mounting plate of the sliding device, as a tip / tail protector for protecting the tip and / or tail of the sliding device, etc.

[0077] For example and without being limitative, other articles or components which would benefit from the increased mechanical properties of the aluminum alloy produced using the above-described method of manufacture can include other sports articles and especially those including a shaft or tube such as, ski poles, baseball bats, hockey sticks, golf sticks, bicycle frames, climbing axes etc.

[0078] One skilled in the art will understand that aerospace articles or components produced using the above-described method of manufacture would also benefit from the increased mechanical properties of the aluminum alloy disclosedabove as these components require a good balance between weight and performance characteristics, such as stiffness, durability, strength or the like.

[0079] The above examples of articles or components which could benefit from aluminum alloy produced using the above-described method of manufacture are understood to be given as exemplary only, given that the articles or components which could benefit from aluminum alloy produced using the above-described method of manufacture are varied and cannot be listed exhaustively. Indeed, articles from many fields such as automobile, train, bus, boat or the like easily come to mind.

[0080] Several alternative embodiments and examples have been described and illustrated herein. The embodiments of the invention described above are intended to be exemplary only. A person of ordinary skill in the art would appreciate the features of the individual embodiments, and the possible combinations and variations of the components. A person of ordinary skill in the art would further appreciate that any of the embodiments could be provided in any combination with the other embodiments disclosed herein. It is understood that the invention could be embodied in other specific forms without departing from the central characteristics thereof. The present examples and embodiments, therefore, are to be considered in all respects as illustrative and not restrictive, and the invention is not to be limited to the details given herein. Accordingly, while the specific embodiments have been illustrated and described, numerous modifications come to mind. The scope of the invention is therefore intended to be limited solely by the scope of the appended claims.

Claims

CLAIMS:

1. A method for producing a sheet or plate of aluminum alloy, the method comprising the steps of: casting the alloy, the alloy having a composition including the following elements in the specified range in percentage by weight: 6.80 - 10.00% Zn, 2.20 - 3.50% Mg, 1.30 - 4.00% Cu, 0.01 - 0.30% Sc, 0.05 - 0.20% Zr; cold rolling of the aluminum alloy sheet or plate, this step being performed at room temperature with a reduction rate of between about 5% and about 20% per pass; applying a solution heat treatment to the sheet or plate of aluminum alloy, this step being performed by heating the sheet or plate of aluminum alloy to a temperature of between about 400 °C and about 500 °C; quenching the sheet or plate of aluminum alloy; and performing an artificial ageing treatment, this step being performed by heating the sheet or plate of aluminum alloy to a temperature of between about 80 °C and about 200 °C and maintaining the sheet or plate of aluminum alloy at this temperature for a time period of between about 30 minutes and about 100 hours.

2. The method of claim 1 , wherein the step of cold rolling of the aluminum alloy sheet or plate allows a reduction between about 20 % and about 95% of the thickness of the ingot.

3. The method of claim 2, wherein the step of cold rolling of the aluminum alloy sheet or plate allows a reduction between about 50 % and about 95% of the thickness of the ingot.

4. The method of any one of claims 1 to 3, further comprising the step of homogenizing the alloy ingot, this step being performed at a maximum temperature of between about 400 °C and about 500 °C.

5. The method of claim 4, wherein the step of homogenizing the alloy ingot is performed for a time period of between about 4 hours and about 26.5 hours.

6. The method of claim 4 or 5, wherein the step of homogenizing the alloy ingot includes performing hot isostatic pressing of the ingot, this step being performed at a temperature of between about 300 °C and about 500 °C, for a time period of between about 1 hour to 5 hours, while an isostatic pressure of between about 10 000 psi and about 20 000 psi, is applied simultaneously on the ingot.

7. The method of any one of claims 1 to 6, further comprising performing hot rolling of the previously homogenized aluminum alloy ingot, this step being performed at a temperature of between about 400 °C and about 500 °C, with a reduction rate of between about 5% and about 20% per pass and prior to the step of cold rolling of the aluminum alloy sheet or plate.

8. The method of claim 7, further comprising fully annealing the previously hot rolled aluminum alloy sheet or plate, this step being performed at a temperature of between about 365 °C and about 465 °C, for a time period of between about 15 minutes and 5 hours.

9. The method of claim 8, wherein a step of cooling of the aluminum alloy sheet or plate at a rate of about 30°C / h until a temperature of the aluminum alloy sheet or plate of about 260°C is reached is provided following the step of fully annealing the previously hot rolled aluminum alloy sheet or plate.

10. The method of any one of claims 1 to 9, including performing at least one intermediate partial annealing of the aluminum alloy sheet or plate, between passes of the cold rolling of the aluminum alloy sheet or plate.

11. The method of claim 10, wherein, the intermediate partial annealing is performed at a temperature of between about 200 °C and about 500 °C, for a time period of between about 1 minute and 4 hours.

12. The method of any one of claims 1 to 11 , further including stretching of the sheet or plate of aluminum alloy before the step of performing the artificial ageing treatment.

13. A sliding device including at least one sheet or plate of aluminum alloy manufactured using the method for producing a sheet or plate of aluminum alloy of any one of claims 1 to 12 integrated thereto.

14. The sliding device of claim 13, the sliding device including a core with the at least one sheet or plate of aluminum alloy being laminated to the core.

15. A sporting article comprising an aluminum alloy, the aluminum alloy being manufactured using the method for producing a sheet or plate of aluminum alloy of any one of claims 1 to 12.

16. An aerospace article or component comprising an aluminum alloy, the aluminum alloy being manufactured using the method for producing a sheet or plate of aluminum alloy of any one of claim 1 to 12.

17. Use of an aluminum alloy being manufactured using the method for producing a sheet or plate of aluminum alloy of any one of claim 1 to 12 in the manufacture of an article or component.

18. Use of an aluminum alloy of claim 17, wherein the article or component is at least one of a sporting article or component, an aerospace article or component, a medical device article or component and a transport vehicle article or component.

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