US20110209801A2 - Aluminum-Copper-Lithium Alloy With Improved Mechanical Strength and Toughness - Google Patents
Aluminum-Copper-Lithium Alloy With Improved Mechanical Strength and Toughness Download PDFInfo
- Publication number
- US20110209801A2 US20110209801A2 US12/820,495 US82049510A US2011209801A2 US 20110209801 A2 US20110209801 A2 US 20110209801A2 US 82049510 A US82049510 A US 82049510A US 2011209801 A2 US2011209801 A2 US 2011209801A2
- Authority
- US
- United States
- Prior art keywords
- weight
- mpa
- yield strength
- product
- thickness
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 239000001989 lithium alloy Substances 0.000 title claims description 12
- -1 Aluminum-Copper-Lithium Chemical compound 0.000 title claims description 6
- 229910000733 Li alloy Inorganic materials 0.000 title claims description 6
- 238000000034 method Methods 0.000 claims abstract description 16
- 229910052782 aluminium Inorganic materials 0.000 claims abstract description 13
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims abstract description 13
- 230000008569 process Effects 0.000 claims abstract description 10
- 229910000838 Al alloy Inorganic materials 0.000 claims abstract description 8
- 230000032683 aging Effects 0.000 claims description 39
- 229910045601 alloy Inorganic materials 0.000 claims description 28
- 239000000956 alloy Substances 0.000 claims description 28
- 239000011777 magnesium Substances 0.000 claims description 25
- 239000010949 copper Substances 0.000 claims description 21
- 239000011701 zinc Substances 0.000 claims description 17
- 239000011572 manganese Substances 0.000 claims description 15
- 230000003068 static effect Effects 0.000 claims description 15
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 14
- 229910052744 lithium Inorganic materials 0.000 claims description 13
- 239000000203 mixture Substances 0.000 claims description 13
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 claims description 12
- 229910052749 magnesium Inorganic materials 0.000 claims description 12
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 claims description 11
- 239000010936 titanium Substances 0.000 claims description 11
- 229910052802 copper Inorganic materials 0.000 claims description 9
- 238000010791 quenching Methods 0.000 claims description 9
- 229910052709 silver Inorganic materials 0.000 claims description 9
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 8
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 claims description 8
- 238000010276 construction Methods 0.000 claims description 8
- 239000004332 silver Substances 0.000 claims description 8
- 230000000171 quenching effect Effects 0.000 claims description 7
- 229910052710 silicon Inorganic materials 0.000 claims description 7
- 229910052725 zinc Inorganic materials 0.000 claims description 7
- 229910001338 liquidmetal Inorganic materials 0.000 claims description 6
- 229910052748 manganese Inorganic materials 0.000 claims description 6
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims description 5
- 229910052804 chromium Inorganic materials 0.000 claims description 5
- 229910052742 iron Inorganic materials 0.000 claims description 5
- 239000010703 silicon Substances 0.000 claims description 5
- 229910052719 titanium Inorganic materials 0.000 claims description 5
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 claims description 4
- 238000010438 heat treatment Methods 0.000 claims description 4
- 238000005482 strain hardening Methods 0.000 claims description 4
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 claims description 3
- 241000256259 Noctuidae Species 0.000 claims description 2
- 238000005266 casting Methods 0.000 claims description 2
- 238000004519 manufacturing process Methods 0.000 abstract description 6
- 238000012360 testing method Methods 0.000 description 13
- 238000005259 measurement Methods 0.000 description 7
- 229910017539 Cu-Li Inorganic materials 0.000 description 6
- 230000007797 corrosion Effects 0.000 description 5
- 238000005260 corrosion Methods 0.000 description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 5
- 238000011156 evaluation Methods 0.000 description 4
- 230000007423 decrease Effects 0.000 description 3
- 238000005096 rolling process Methods 0.000 description 3
- 229910052726 zirconium Inorganic materials 0.000 description 3
- 239000002970 Calcium lactobionate Substances 0.000 description 2
- QCWXUUIWCKQGHC-UHFFFAOYSA-N Zirconium Chemical compound [Zr] QCWXUUIWCKQGHC-UHFFFAOYSA-N 0.000 description 2
- 238000003483 aging Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 238000001816 cooling Methods 0.000 description 2
- 230000002349 favourable effect Effects 0.000 description 2
- 238000005242 forging Methods 0.000 description 2
- 238000000265 homogenisation Methods 0.000 description 2
- 230000006872 improvement Effects 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 230000035945 sensitivity Effects 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- 230000035882 stress Effects 0.000 description 2
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 description 1
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 1
- 125000000218 acetic acid group Chemical class C(C)(=O)* 0.000 description 1
- 230000004913 activation Effects 0.000 description 1
- AZDRQVAHHNSJOQ-UHFFFAOYSA-N alumane Chemical class [AlH3] AZDRQVAHHNSJOQ-UHFFFAOYSA-N 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 230000033228 biological regulation Effects 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000005097 cold rolling Methods 0.000 description 1
- 230000008094 contradictory effect Effects 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000018109 developmental process Effects 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 229910052735 hafnium Inorganic materials 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 230000000977 initiatory effect Effects 0.000 description 1
- 238000003754 machining Methods 0.000 description 1
- 230000014759 maintenance of location Effects 0.000 description 1
- 238000000691 measurement method Methods 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000003801 milling Methods 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000007670 refining Methods 0.000 description 1
- 229910052706 scandium Inorganic materials 0.000 description 1
- 239000007921 spray Substances 0.000 description 1
- 239000003381 stabilizer Substances 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- 239000003351 stiffener Substances 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000009864 tensile test Methods 0.000 description 1
- 229910052720 vanadium Inorganic materials 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C21/00—Alloys based on aluminium
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C21/00—Alloys based on aluminium
- C22C21/12—Alloys based on aluminium with copper as the next major constituent
- C22C21/16—Alloys based on aluminium with copper as the next major constituent with magnesium
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
- C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
- C22F1/04—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working of aluminium or alloys based thereon
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
- C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
- C22F1/04—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working of aluminium or alloys based thereon
- C22F1/057—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working of aluminium or alloys based thereon of alloys with copper as the next major constituent
Definitions
- the invention relates to aluminum-copper-lithium alloy products, and more specifically, such products and processes for production and use thereof, in particular in the field of aeronautical and aerospace construction.
- Products in particular thick rolled, forged or extruded aluminum alloy products, are developed in order to produce, by cutting, surface milling or machining from the solids, high-strength parts intended in particular for the aeronautical industry, the aerospace industry or mechanical construction.
- Aluminum alloys comprising lithium are very beneficial in this regard because lithium can reduce the density of aluminum by 3% and increase the modulus of elasticity by 6% for each weight percent of lithium added.
- their performance with respect to other usage properties must be as good as that of commonly used alloys, in particular in terms of the compromise between the static mechanical strength properties (yield strength, ultimate tensile strength) and the damage tolerance properties (fracture toughness, resistance to fatigue crack propagation), these properties generally being contradictory.
- these properties must particularly be obtained at the quarter- and half-thickness, and the products therefore must have low quench sensitivity. It is said that a product is quench sensitive if these static mechanical properties, such as the yield strength, decrease when the quenching rate decreases.
- the quenching rate is the average cooling rate of the product during quenching.
- These alloys must also have sufficient corrosion resistance, be capable of being formed according to usual processes and have low residual stress so as to be capable of being integrally machined.
- U.S. Pat. No. 5,032,359 describes a very large family of aluminum-copper-lithium alloys in which the addition of, magnesium and silver, in particular between 0.3 and 0.5 percent by weight, enables the mechanical strength to be increased.
- U.S. Pat. No. 5,234,662 describes alloys with the following composition (in weight percent): Cu: 2.60-3.30, Mn: 0.0-0.50, Li: 1.30-1.65, Mg: 0.0-1.8, and elements controlling the granular structure chosen from Zr and Cr: 0.0-1.5.
- U.S. Pat. No. 7,438,772 describes alloys comprising, in weight percentages: Cu: 3-5, Mg: 0.5-2, Li: 0.01-0.9 and discourages the use of higher lithium contents due to degradation of the compromise between toughness and mechanical strength.
- U.S. Pat. No. 7,229,509 describes an alloy comprising (weight %): (2.5-5.5) Cu, (0.1-2.5) Li, (0.2-1.0) Mg, (0.2-0.8) Ag, (0.2-0.8) Mn, 0.4 max Zr or other grain-refining agents such as Cr, Ti, Hf, Sc or V, in particular having a toughness K 1C (L)>37.4 MPa ⁇ m for a yield strength of R p0.2 (L)>448.2 MPa (products with a thickness above 76.2 mm) and in particular a toughness K 1C (L)>38.5 MPa ⁇ m for a yield strength of R p0.2 (L)>489.5 MPa (products with a thickness below 76.2 mm).
- US Patent Application No 2009/142222 A1 describes alloys comprising (in weight 3%), 34 to 4.2% Cu, 0.9 to 1.4% Li, 0.3 to 0.7% Ag, 0.1 to 0.6% Mg, 0.2 to 0.8% Zn, 0.1 to 0.6% Mn and 0.01 to 0.6% of at least one element for controlling the granular structure.
- alloy AA2050 which includes (weight %): (3.02-3.9) Cu, (0.7-1.3) Li, (0.20-0.6) Mg, (0.20-0.7) Ag, 0.25 max. Zn, (0.20-0.50) Mn, (0.06-0.14) Zr and alloy AA2095 (3.7-4.3) Cu, (0.7-1.5) Li, (0.25-0.8) Mg, (0.25-0.6) Ag, 0.25 max. Zn, 0.25 max. Mn, (0.04-0.18) Zr. Products of alloy AA2050 are known for their quality in terms of static mechanical strength and toughness.
- the invention first relates to a wrought, product such as an extruded, rolled and/or forged aluminum alloy-based product, comprising, in weight %:
- the invention secondly relates to a method to manufacture an extruded, rolled and/or forged aluminum alloy-based product in which:
- said unwrought shape is homogenized at a temperature of between 450° C. and 550° and preferably between 480° C. and 530° C. for a period of between 5 and 60 hours;
- said unwrought shape is hot and optionally cold worked into an extruded, rolled and/or forged product
- said product is aged artificially, by heating at a temperature of from 130 to 170° C. for 5 to 100 hours and preferably from 10 to 40 h so as to obtain a yield strength close to the peak.
- the invention also relates to a structural element comprising a product according to the invention.
- the invention also relates to the use of a structural element according to the invention for aeronautical construction.
- FIG. 2 Results of the yield strength and toughness obtained for the samples of example 1.
- FIG. 4 Results of the yield strength and toughness obtained for the samples of example 3, with the yield strength being close to the peak.
- the static mechanical properties in other words the ultimate tensile strength R m , the conventional yield strength at 0.2% elongation R p0.2 (“yield strength”) and the elongation at rupture A %, are determined by a tensile test according to standard EN 10002-1, with the sample and the direction of the test being defined by standard EN 485-1.
- K Q The stress intensity factor
- ASTM E 399 gives criteria making it possible to determine whether K Q is a valid value of K 1C .
- the values of K Q obtained for different materials are comparable to one another insofar as the yield strengths of the materials are on the same order of magnitude.
- the thickness of the profiles is defined according to standard EN 2066:2001: the transverse cross-section is divided into basic rectangles with dimensions A and B; A is always the largest dimension of the basic rectangle and B can be considered to be the thickness of the basic rectangle.
- the die holder is the basic rectangle having the largest dimension A.
- the MASTMAASIS (Modified ASTM Acetic Acid Salt Intermittent Spray) is performed according to standard ASTM G85.
- structural element or “structural element” of a mechanical construction will refer to a mechanical part for which the static and/or dynamic mechanical properties are particularly important for the performance of the structure, and for which a structural calculation is normally prescribed or performed. This typically involves elements of which the failure is likely to endanger said construction, users thereof or others.
- these structural elements include tin particular the fuselage (such as the fuselage skin), the stringers, the bulkheads, the circumferential frames, the wing skins, the stringers or stiffeners, the ribs and spars and the tail unit comprised in particular of horizontal and vertical stabilizers, as well as floor beams, seat tracks and doors.
- the present inventors have surprisingly noted that according to embodiments of the present invention, it is possible to improve the compromise between the static mechanical resistance properties and the damage tolerance properties, in particular of thick aluminum-copper-lithium alloy products such as, in particular, alloy AA2050 by increasing the magnesium content.
- the choice of copper, magnesium and lithium contents enables a favorable compromise of properties to be achieved, and satisfactory thermal stability of the product to be obtained.
- the copper content of the products according to the invention is advantageously from 3.0 to 3.9% by weight. In an advantageous embodiment of the invention, the copper content is from 3.2 to 3.7% by weight.
- the copper content is too high, the toughness may be insufficient, in particular for near-peak aging processes, and, moreover, the density of the alloy may not be advantageous.
- the copper content is too low, the minimum static mechanical properties may not be capable of being achieved.
- the lithium content of the products according to the present invention is advantageously from 0.8 to 13% by weight.
- the lithium content is from 0.9 to 1.2% by weight.
- the lithium content is at least 0.93% by weight or even at least 0.94% by weight.
- the density reduction associated with the addition of lithium may be insufficient.
- the magnesium content of the products according to the present invention is advantageously from 0.6 to 1.2% by weight and preferably from 0.65 or 0.67 to 1.0% by weight. In an advantageous embodiment of the present invention, the magnesium content is at most 0.9% by weight and preferably at most 0.8% by weight. For certain applications, it may be advantageous for the magnesium content to be at least 0.7%.
- the zirconium content is advantageously from 0.05 to 0.18% by weight and preferably between 0.08 and 0.14% by weight so as to preferably obtain a fibrous or slightly recrystallized grain structure.
- the silver content is advantageously from 0.0 to 0.5% by weight.
- the present inventors have noted that, although the presence of silver is advantageous, in the presence of a magnesium amount according to the present invention, a large amount of silver may not be necessary for obtaining an improvement desired in the compromise between the mechanical strength and the damage tolerance. The limitation of the amount of silver is generally economically highly favorable.
- the silver content is from 0.15 to 0.35% by weight.
- the silver content is preferably not more than 0.25% by weight.
- the sum of the iron content and the silicon content is preferably not more than 0.20% by weight.
- the iron and silicon contents are each not more than 0.08% by weight.
- the iron and silicon contents are at most 0.06 and 0.04% by weight, respectively.
- a controlled and limited iron and silicon content can contribute to an improvement in the compromise between mechanical strength and damage tolerance.
- the alloy also advantageously contains at least one element capable of contributing to the control of the grain size selected from among Cr, Sc, Hf and Ti, with the amount of the element, if chosen, being between 0.05 and 0.3% by weight for Cr and for Sc, 0.050 to 0.5% by weight for Hf 0.01 to 0.15% by weight for Ti.
- titanium is chosen in an amount of 0.02 and 0.10% by weight.
- Zinc is an undesirable impurity.
- the zinc content is preferably Zn ⁇ 0.15% by weight and preferably Zn ⁇ 0.05% by weight.
- Zinc content is advantageously not more than 0.04% by weight.
- the density of products according to the present invention is advantageously not more than 2.72 g/cm 3 .
- An advantageous alloy according to the present invention is particularly intended for producing thick, extruded, rolled and/or forged products.
- thick products in the context of the present invention, is intended products of which the thickness is at least 30 mm and preferably at least 50 mm.
- an advantageous alloy according to the present invention preferably has a low quenching sensitivity, which is particularly advantageous for thick products.
- Rolled products according to the present invention preferably have a thickness of from 30 to 200 mm and more preferably from 50 to 170 mm.
- the thick products according to the present invention have a particularly advantageous compromise between mechanical strength and toughness.
- a product according to the present invention in a rolled state, solution treated, quenched and aged so as to reach near-peak yield strength, advantageously has, at half-thickness at least one of the following pairs of properties for thicknesses from 30 to 100 mm.
- a tensile yield strength R p0.2 (L) and an elongation at rupture A % (L) having a difference with a tensile yield strength R p0.2 (L) and an elongation at rupture A % (L) before thermal exposure of less than 10%, and preferably less than 5%.
- a product according to the present invention in a rolled state, solution treated, quenched and aged so as to reach near-peak yield strength, advantageously has, at least one of the following pairs of properties at half-thickness for thicknesses from 10 to 30 mm:
- a tensile yield strength R p0.2 (L) and an elongation at rupture A % (L) having a difference with a tensile yield strength R p0.2 (L) and an elongation at rupture A % (L) before thermal exposure of less than 10%, and preferably less than 5%.
- Products according to embodiments of the present invention also have advantageous properties in terms of fatigue behavior with regard to both crack initiation (s/N) and propagation rate (da/dN).
- the corrosion resistance of the products of the present invention is generally high; thus, the MASTMAASIS test result (standards ASTMG85 & G34) is at least EA and preferably P for the products according to the present invention.
- a suitable process for producing products according to the present invention includes steps of development, casting, hot working, solution, treating, quenching and aging. A suitable process is described below.
- a liquid metal bath is prepared so as to obtain an aluminum alloy with a composition according to the invention.
- the liquid metal bath is then cast as an unwrought shape, such as a billet, a rolling ingot or a forging stock.
- the unwrought shape is then homogenized at a temperature of between 450° C. and 550° and preferably between 480° C. and 530° C. for a period of between 5 and 60 hours.
- the unwrought shape is generally cooled to room temperature before being preheated so as to be hot worked.
- the preheating is intended to reach a temperature preferably between 400 and 500° C. and more preferably on the order of 450° C., enabling the raw product to be worked.
- the hot working and optionally cold working is typically performed by extruding, rolling and/or forging, so as to obtain an extruded, rolled and/or forged product of which the thickness is preferably at least 30 mm.
- the product thus obtained is then solution heat treated by solution heat treatment at between 490 and 530° C. for 15 min to 8 hours, then typically quenched with water at room temperature or preferably with cold water.
- the product is then subjected to a controlled stretching with a permanent set of 1 to 6% and preferably at least 2%.
- the rolled products are preferably subjected to controlled stretching with a permanent set of above 3%.
- the controlled stretching is performed with a permanent set of between 3 and 5%.
- a preferred metallurgical temper is T84.
- Known steps such as rolling, flattening, straightening and forming can optionally be performed after solution heat treating and quenching and before or after the controlled stretching.
- a step of cold rolling of at least 7% and preferably at least 9% is carried out before performing a controlled stretching with a permanent set of 1 to 3%.
- the yield strength increases with the artificial aging time at a given temperature to a maximum value called the hardening peak or “peak”, then decreases with the aging time.
- the term aging curve will refer to the change in the yield strength as a function of the equivalent aging time at 155° C.
- An example of an aging curve is provided in FIG. 1 .
- the yield strength of a point N on the aging curve is considered to be close to the peak yield strength if the absolute value of the slope P N is at most 3 MPa/h.
- an under-aged temper is a temper for which P N is positive and an over-aged temper is a temper for which P N is negative.
- t i ⁇ exp ⁇ ( - 16400 / T ) ⁇ d t exp ⁇ ( - 16400 / T ref )
- T in Kelvin
- T ref is a reference temperature set at 428 K.
- t i is expressed in hours.
- the yield strength close to the peak yield strength is typically equal to at least 90%, generally even equal to fat least 95% and frequently at least 97% of the peak yield strength R p0.2 .
- the maximum peak yield strength can be obtained by varying the time and temperature parameters of the aging.
- the peak yield strength is generally considered to bed satisfactory when the aging time is varied between 10 and 70 h for a temperature of 155° C. after a stretching of 3.5%.
- the clearly under-aged tempers correspond to compromises between the static mechanical strength (R p0.2 , R m ) and the damage tolerance (toughness, fatigue crack propagation resistance) that are better than at the peak and especially beyond the peak.
- R p0.2 , R m the static mechanical strength
- R m the damage tolerance
- the present inventors have noted that a near-peak under-aged temper may enable a beneficial damage tolerance to be obtained, while also improving the performances in terms of corrosion resistance and thermal stability.
- the use of a near-peak under-aged temper can enable the robustness of the industrial process to be improved: a variation in the aging conditions leads to a low variation in the properties obtained.
- Products according to the present invention can advantageously be used for example, in structural elements, in particular for airplanes.
- the use of a structural element incorporating at least one product according to the present invention and/or manufactured from such a product is advantageous, in particular for aeronautical construction.
- Products according to the present invention are particularly advantageous in the production of products machined from solids, such as in particular underwing or upper wing elements of which the skin and stringers are obtained from the same starting material, spars and ribs, as well as any other use in which these properties might be advantageous.
- the slabs were homogenized at around 500° C. for around 12 hours, then cut and scalped so as to obtain parts with dimensions of 400 ⁇ 335 ⁇ 90 mm.
- the parts were hot rolled to obtain plates with a thickness of 20 mm.
- the plates were solution treated at 505+/ ⁇ 2° C. for 1 h, quenched with water at 75° C. so as to obtain a cooling rate of around 18° C./s and thus simulate the properties obtained at half-thickness in a plate with a thickness of 80 mm.
- the plates were then stretched with a permanent elongation of 3.5%.
- the plates were subjected to artificial aging for between 10 h and 50 h at 155° C. Samples were taken at half-thickness in order to measure the static mechanical tensile properties as well as the toughness K Q .
- the products according to the invention have a significantly improved compromise in properties over reference samples.
- the slabs were homogenized, then scalped. After homogenization, the slabs were hot rolled in order to obtain plates with a thickness of 50 mm. The plates were solution treated, quenched with cold water and stretched with a permanent elongation of between 3.5% and 4.5%
- points 8 , 9 and 10 have been added to FIG. 2 (slope P N between 0 and 3), although they concern test pieces of different shapes for the measurement of K Q (K 1C ) so as to facilitate the comparison between the invention and the prior art. It is thus confirmed that the products according to the invention have an improved compromise in properties over the prior art.
- the slabs were homogenized fat around 500° C. for around 12 hours, then cut and scalped so as to obtain parts with dimensions of 400 ⁇ 335 ⁇ 90 mm.
- the parts were hot rolled to obtain plates with a thickness of 20 mm.
- the plates were solution treated at 505+/ ⁇ 2° C. for 1 h, and quenched with cold water. The plates were then stretched with a permanent elongation of 3.5%.
- the plates were subjected to artificial aging for between 18 h and 72 h at 155° C. Samples were taken at half-thickness in order to measure the static mechanical tensile properties as well as the toughness K Q .
- the products according to the invention have a significantly improved compromise in properties over reference samples.
- thermal stability of products made of alloy 12 were compared for different aging conditions. Plates made of alloy 12 and manufactured according to the method described in example 3 until the artificial aging step excluded underwent artificial aging at 155° C. or at 143° C. for the increasing durations indicated in Table 7. Plates which were artificially aged 34 h at 143° C. or 40 h at 155° C. were subsequently thermally tested for 1000 hours at 85° C. Samples were taken at half-thickness in order to measure the static mechanical tensile properties before and after thermal exposure.
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Heat Treatment Of Steel (AREA)
- Conductive Materials (AREA)
Abstract
Description
- This application claims priority to U.S. Provisional Application 61/220,249 filed Jun. 25, 2009 and FR 09/03096 filed Jun. 25, 2009, the contents of which are incorporated herein by reference in their entireties.
- 1. Field of the Invention
- The invention relates to aluminum-copper-lithium alloy products, and more specifically, such products and processes for production and use thereof, in particular in the field of aeronautical and aerospace construction.
- 2. Description of Related Art
- Products, in particular thick rolled, forged or extruded aluminum alloy products, are developed in order to produce, by cutting, surface milling or machining from the solids, high-strength parts intended in particular for the aeronautical industry, the aerospace industry or mechanical construction.
- Aluminum alloys comprising lithium are very beneficial in this regard because lithium can reduce the density of aluminum by 3% and increase the modulus of elasticity by 6% for each weight percent of lithium added. In order for these alloys to be selected in airplanes, their performance with respect to other usage properties must be as good as that of commonly used alloys, in particular in terms of the compromise between the static mechanical strength properties (yield strength, ultimate tensile strength) and the damage tolerance properties (fracture toughness, resistance to fatigue crack propagation), these properties generally being contradictory. For thick products, these properties must particularly be obtained at the quarter- and half-thickness, and the products therefore must have low quench sensitivity. It is said that a product is quench sensitive if these static mechanical properties, such as the yield strength, decrease when the quenching rate decreases. The quenching rate is the average cooling rate of the product during quenching.
- These mechanical properties must also preferably be stable over time and not be significantly modified by aging at the working temperature. Thus, prolonged use of products in civil aviation applications requires good stability of the mechanical properties, which is simulated for example by thermal exposure for 1000 hours at 85° C.
- These alloys must also have sufficient corrosion resistance, be capable of being formed according to usual processes and have low residual stress so as to be capable of being integrally machined.
- U.S. Pat. No. 5,032,359 describes a very large family of aluminum-copper-lithium alloys in which the addition of, magnesium and silver, in particular between 0.3 and 0.5 percent by weight, enables the mechanical strength to be increased.
- U.S. Pat. No. 5,234,662 describes alloys with the following composition (in weight percent): Cu: 2.60-3.30, Mn: 0.0-0.50, Li: 1.30-1.65, Mg: 0.0-1.8, and elements controlling the granular structure chosen from Zr and Cr: 0.0-1.5.
- U.S. Pat. No. 5,455,003 describes a process for producing Al—Cu—Li alloys that have improved mechanical strength and toughness at cryogenic temperature, in particular owing to suitable strain hardening and aging. This patent recommends in particular the following composition, in weight percentages: Cu: 3.0-45, Li: 0.7-1.1, Ag: 0-0.6, Mg: 0.3-0.6 and Zn: 0-0.75. The problem of thermal stability for civil aeronautics applications is not mentioned in said document because the intended applications are essentially cryogenic storages for rocket launchers or space shuttles.
- U.S. Pat. No. 7,438,772 describes alloys comprising, in weight percentages: Cu: 3-5, Mg: 0.5-2, Li: 0.01-0.9 and discourages the use of higher lithium contents due to degradation of the compromise between toughness and mechanical strength.
- U.S. Pat. No. 7,229,509 describes an alloy comprising (weight %): (2.5-5.5) Cu, (0.1-2.5) Li, (0.2-1.0) Mg, (0.2-0.8) Ag, (0.2-0.8) Mn, 0.4 max Zr or other grain-refining agents such as Cr, Ti, Hf, Sc or V, in particular having a toughness K1C(L)>37.4 MPa√m for a yield strength of Rp0.2(L)>448.2 MPa (products with a thickness above 76.2 mm) and in particular a toughness K1C(L)>38.5 MPa√m for a yield strength of Rp0.2(L)>489.5 MPa (products with a thickness below 76.2 mm). US Patent Application No 2009/142222 A1 describes alloys comprising (in
weight 3%), 34 to 4.2% Cu, 0.9 to 1.4% Li, 0.3 to 0.7% Ag, 0.1 to 0.6% Mg, 0.2 to 0.8% Zn, 0.1 to 0.6% Mn and 0.01 to 0.6% of at least one element for controlling the granular structure. - Also known are alloy AA2050, which includes (weight %): (3.02-3.9) Cu, (0.7-1.3) Li, (0.20-0.6) Mg, (0.20-0.7) Ag, 0.25 max. Zn, (0.20-0.50) Mn, (0.06-0.14) Zr and alloy AA2095 (3.7-4.3) Cu, (0.7-1.5) Li, (0.25-0.8) Mg, (0.25-0.6) Ag, 0.25 max. Zn, 0.25 max. Mn, (0.04-0.18) Zr. Products of alloy AA2050 are known for their quality in terms of static mechanical strength and toughness.
- There is a need for products, in particular thick products made of an aluminum-copper-lithium alloy having improved properties over those of known products, in particular in terms of compromise between properties of static mechanical strength and properties of damage tolerance, thermal stability, corrosion resistance and machinability, while having a low density.
- The invention first relates to a wrought, product such as an extruded, rolled and/or forged aluminum alloy-based product, comprising, in weight %:
- Cu: 3.0-3.9;
- Li: 0.8-1.3;
- Mg: 0.6-1.0;
- Zr: 0.05-0.18;
- Ag: 0.0-0.5;
- Mn: 0.0-0.5;
- Fe+Si≦0.20;
- Zn≦0.15;
- at least one element among:
- Ti: 0.01-0.15;
- Sc: 0.05-0.3;
- Cr: 0.05-0.3;
- Hf: 0.05-0.5;
- other elements ≦0.05 each and ≦0.15 total, remainder aluminum.
- The invention secondly relates to a method to manufacture an extruded, rolled and/or forged aluminum alloy-based product in which:
- a) an aluminum-based liquid metal bath is prepared, comprising 3.0 to 3.9% by weight Cu, 0.8 to 1.3% by weight Li, 0.6 to 1.0% by weight Mg, 0.05 à 0.18% by weight Zr, 0.0 to 0.5%, by weight Ag, 0.0 to 0.5% by weight Mn, at most 0.20% by weight Fe+Si, at most 0.15% by weight Zn, at least one element chosen from among Cr, Sc, Hf and Ti, the amount of said element, if chosen, being from 0.05 to 0.3% by weight for Cr and for Sc, 0.05 to 0.5% by weight for Hf and 0.01 to 0.15% by weight for Ti, the other elements at most 0.05% by weight each, and 0.15% by weight in total, remainder aluminum;
- b) an unwrought shape is cast from said liquid metal bath;
- c) said unwrought shape is homogenized at a temperature of between 450° C. and 550° and preferably between 480° C. and 530° C. for a period of between 5 and 60 hours;
- d) said unwrought shape is hot and optionally cold worked into an extruded, rolled and/or forged product;
- e) said product is solution heat treated at between 490 and 530° C. for 15 min at 8 h and quenched;
- f) said product is stretched in a controlled manner with a permanent set of 1 to 6% and preferably at least 2%;
- g) said product is aged artificially, by heating at a temperature of from 130 to 170° C. for 5 to 100 hours and preferably from 10 to 40 h so as to obtain a yield strength close to the peak.
- The invention also relates to a structural element comprising a product according to the invention.
- The invention also relates to the use of a structural element according to the invention for aeronautical construction.
-
FIG. 1 : Example of a curve of ageing and determination of the slope of the tangent PN. -
FIG. 2 : Results of the yield strength and toughness obtained for the samples of example 1. -
FIG. 3 : Results of the yield strength and toughness obtained for the samples of examples 1 and 2, with the yield strength being close to the peak. -
FIG. 4 Results of the yield strength and toughness obtained for the samples of example 3, with the yield strength being close to the peak. - Unless otherwise indicated, all of the indications relating to the chemical composition of the alloys are expressed as a weight percentage based on the total weight of the alloy. The expression 1.4 Cu means that the copper content expressed in weight % is multiplied by 1.4. The alloys are designated according to the regulations of The Aluminum Association, known to a person skilled in the art. The density is dependent on the composition and is determined by calculation rather than by a weight measurement method. The values are calculated according to the procedure of The Aluminum Association, which is described on pages 2-12 and 2-13 of “Aluminum Standards and Data”. The definitions of metallurgical tempers are indicated in the European standard EN 515.
- Unless otherwise indicated, the static mechanical properties, in other words the ultimate tensile strength Rm, the conventional yield strength at 0.2% elongation Rp0.2 (“yield strength”) and the elongation at rupture A %, are determined by a tensile test according to standard EN 10002-1, with the sample and the direction of the test being defined by standard EN 485-1.
- The stress intensity factor (KQ) is determined according to standard ASTM E 399. Standard ASTM E 399 gives criteria making it possible to determine whether KQ is a valid value of K1C. For a given test piece shape, the values of KQ obtained for different materials are comparable to one another insofar as the yield strengths of the materials are on the same order of magnitude.
- Unless otherwise indicated, the definitions of standard EN 12258 apply. The thickness of the profiles is defined according to standard EN 2066:2001: the transverse cross-section is divided into basic rectangles with dimensions A and B; A is always the largest dimension of the basic rectangle and B can be considered to be the thickness of the basic rectangle. The die holder is the basic rectangle having the largest dimension A.
- The MASTMAASIS (Modified ASTM Acetic Acid Salt Intermittent Spray) is performed according to standard ASTM G85.
- In this document, the term “structure element” or “structural element” of a mechanical construction will refer to a mechanical part for which the static and/or dynamic mechanical properties are particularly important for the performance of the structure, and for which a structural calculation is normally prescribed or performed. This typically involves elements of which the failure is likely to endanger said construction, users thereof or others. For an airplane, these structural elements include tin particular the fuselage (such as the fuselage skin), the stringers, the bulkheads, the circumferential frames, the wing skins, the stringers or stiffeners, the ribs and spars and the tail unit comprised in particular of horizontal and vertical stabilizers, as well as floor beams, seat tracks and doors.
- According to the present invention, it has been discovered that by using a selected class of aluminum alloys that contain specific and important amounts of lithium, copper and magnesium and zirconium, wrought products are able to be prepared with an improved compromise between toughness and mechanical strength, and good corrosion resistance. In addition, these products, when they are subjected to an aging process chosen so as to obtain a yield strength Rp0.2 close to the peak yield strength Rp0.2, have excellent thermal stability.
- The present inventors have surprisingly noted that according to embodiments of the present invention, it is possible to improve the compromise between the static mechanical resistance properties and the damage tolerance properties, in particular of thick aluminum-copper-lithium alloy products such as, in particular, alloy AA2050 by increasing the magnesium content. In particular, for thick products having been subjected to near-peak aging, the choice of copper, magnesium and lithium contents enables a favorable compromise of properties to be achieved, and satisfactory thermal stability of the product to be obtained.
- The copper content of the products according to the invention is advantageously from 3.0 to 3.9% by weight. In an advantageous embodiment of the invention, the copper content is from 3.2 to 3.7% by weight. When the copper content is too high, the toughness may be insufficient, in particular for near-peak aging processes, and, moreover, the density of the alloy may not be advantageous. When the copper content is too low, the minimum static mechanical properties may not be capable of being achieved.
- The lithium content of the products according to the present invention is advantageously from 0.8 to 13% by weight. Advantageously, the lithium content is from 0.9 to 1.2% by weight. Preferably, the lithium content is at least 0.93% by weight or even at least 0.94% by weight. When the lithium content is too low, the density reduction associated with the addition of lithium may be insufficient.
- The magnesium content of the products according to the present invention is advantageously from 0.6 to 1.2% by weight and preferably from 0.65 or 0.67 to 1.0% by weight. In an advantageous embodiment of the present invention, the magnesium content is at most 0.9% by weight and preferably at most 0.8% by weight. For certain applications, it may be advantageous for the magnesium content to be at least 0.7%.
- The zirconium content is advantageously from 0.05 to 0.18% by weight and preferably between 0.08 and 0.14% by weight so as to preferably obtain a fibrous or slightly recrystallized grain structure.
- The manganese content is advantageously from 0.0 and 0.5% by weight. In particular in the production of thick sheets, the manganese content is preferably from 0.2 to 0.4% by weight which typically enables the toughness to be improved without compromising mechanical strength.
- The silver content is advantageously from 0.0 to 0.5% by weight. The present inventors have noted that, although the presence of silver is advantageous, in the presence of a magnesium amount according to the present invention, a large amount of silver may not be necessary for obtaining an improvement desired in the compromise between the mechanical strength and the damage tolerance. The limitation of the amount of silver is generally economically highly favorable. In an advantageous embodiment of the invention, the silver content is from 0.15 to 0.35% by weight. In an embodiment of the present invention, which has the advantage of typically minimizing density, the silver content is preferably not more than 0.25% by weight.
- The sum of the iron content and the silicon content is preferably not more than 0.20% by weight. Preferably, the iron and silicon contents are each not more than 0.08% by weight. In an advantageous embodiment of the present invention, the iron and silicon contents are at most 0.06 and 0.04% by weight, respectively. A controlled and limited iron and silicon content can contribute to an improvement in the compromise between mechanical strength and damage tolerance.
- The alloy also advantageously contains at least one element capable of contributing to the control of the grain size selected from among Cr, Sc, Hf and Ti, with the amount of the element, if chosen, being between 0.05 and 0.3% by weight for Cr and for Sc, 0.050 to 0.5% by weight for Hf 0.01 to 0.15% by weight for Ti. Preferably, titanium is chosen in an amount of 0.02 and 0.10% by weight.
- Zinc is an undesirable impurity. The zinc content is preferably Zn≦0.15% by weight and preferably Zn≦0.05% by weight. Zinc content is advantageously not more than 0.04% by weight.
- The density of products according to the present invention is advantageously not more than 2.72 g/cm3. To reduce the density of products, it may be advantageous to select the composition so as to obtain a density of not more than 2.71 g/cm3 and preferably not more than 2.70 g/cm3.
- An advantageous alloy according to the present invention is particularly intended for producing thick, extruded, rolled and/or forged products. By thick products, in the context of the present invention, is intended products of which the thickness is at least 30 mm and preferably at least 50 mm. Indeed, an advantageous alloy according to the present invention preferably has a low quenching sensitivity, which is particularly advantageous for thick products.
- Rolled products according to the present invention preferably have a thickness of from 30 to 200 mm and more preferably from 50 to 170 mm.
- The thick products according to the present invention have a particularly advantageous compromise between mechanical strength and toughness.
- A product according to the present invention, in a rolled state, solution treated, quenched and aged so as to reach near-peak yield strength, advantageously has, at half-thickness at least one of the following pairs of properties for thicknesses from 30 to 100 mm.
- (i) for thicknesses of 30 to 60 mm, at half-thickness, a yield strength Rp0.2(L)≧525 MPa and preferably Rp0.2(L)≧545 MPa and a toughness K1C (L−T)≧38 MPa√m and preferably K1C (L−T)≧43 MPa√m,
- (ii) for thicknesses of 60 to 100 mm at half-thickness, a yield strength Rp0.2(L)≧515 MPa and preferably Rp0.2(L)≧535 MPa and a toughness K1C (L−T)≧35 MPa√m and preferably K1C (L−T)≧40 MPa√m,
- (iii) for thicknesses of 100 to 130 mm, at half-thickness, a yield strength Rp0.2(L)≧505 MPa and preferably Rp0.2(L)≧525 MPa and a toughness K1C (L−T)≧32 MPa√m and preferably K1C (L−T)≧37 MPa√m,
- (iv) for thicknesses of 30 to 100 mm, at half-thickness, a yield strength Rp0.2(L) expressed in MPa and a toughness K1C (L−T) expressed in MPa√m so that K1C (L−T)≧−0.217 Rp0.2(L)+157 and preferably K1C (L−T)≧−0.217 Rp0.2 (L)+163 and greater than 35 MPa √m;
- (v) after thermal exposure for 1000 hours at 85° C., a tensile yield strength Rp0.2 (L) and an elongation at rupture A % (L) having a difference with a tensile yield strength Rp0.2(L) and an elongation at rupture A % (L) before thermal exposure of less than 10%, and preferably less than 5%.
- In another embodiment, thinner products, with a thickness comprised from 10 to 30 mm, typically around 20 mm, are however preferred because the compromise between mechanical strength and toughness in these conditions is particularly advantageous.
- A product according to the present invention, in a rolled state, solution treated, quenched and aged so as to reach near-peak yield strength, advantageously has, at least one of the following pairs of properties at half-thickness for thicknesses from 10 to 30 mm:
- (i) a yield strength Rp0.2(L)≧525 MPa and preferably Rp0.2(L)≧545 MPa and a toughness K1C (L−T)≧40 MPa√m and preferably K1C (L−T)≧45 MPa√m,
- (ii) a yield strength Rp0.2 (L) expressed in MPa and a toughness K1C (L−T) expressed in MPa√m so that K1C (L−T)≧−0.4 Rp0.2(L)+265 and preferably K1C (L−T)≧−0.4 Rp0.2(L)+270 and greater than 45 MPa √m,
- (iii) after thermal exposure for 1000 hours at 85° C., a tensile yield strength Rp0.2(L) and an elongation at rupture A % (L) having a difference with a tensile yield strength Rp0.2(L) and an elongation at rupture A % (L) before thermal exposure of less than 10%, and preferably less than 5%.
- Products according to embodiments of the present invention also have advantageous properties in terms of fatigue behavior with regard to both crack initiation (s/N) and propagation rate (da/dN).
- The corrosion resistance of the products of the present invention is generally high; thus, the MASTMAASIS test result (standards ASTMG85 & G34) is at least EA and preferably P for the products according to the present invention.
- A suitable process for producing products according to the present invention includes steps of development, casting, hot working, solution, treating, quenching and aging. A suitable process is described below.
- In a first step, a liquid metal bath is prepared so as to obtain an aluminum alloy with a composition according to the invention.
- The liquid metal bath is then cast as an unwrought shape, such as a billet, a rolling ingot or a forging stock.
- The unwrought shape is then homogenized at a temperature of between 450° C. and 550° and preferably between 480° C. and 530° C. for a period of between 5 and 60 hours.
- After homogenization, the unwrought shape is generally cooled to room temperature before being preheated so as to be hot worked. The preheating is intended to reach a temperature preferably between 400 and 500° C. and more preferably on the order of 450° C., enabling the raw product to be worked.
- The hot working and optionally cold working is typically performed by extruding, rolling and/or forging, so as to obtain an extruded, rolled and/or forged product of which the thickness is preferably at least 30 mm. The product thus obtained is then solution heat treated by solution heat treatment at between 490 and 530° C. for 15 min to 8 hours, then typically quenched with water at room temperature or preferably with cold water. The product is then subjected to a controlled stretching with a permanent set of 1 to 6% and preferably at least 2%. The rolled products are preferably subjected to controlled stretching with a permanent set of above 3%. In an advantageous embodiment of the invention, the controlled stretching is performed with a permanent set of between 3 and 5%. A preferred metallurgical temper is T84. Known steps such as rolling, flattening, straightening and forming can optionally be performed after solution heat treating and quenching and before or after the controlled stretching. In an embodiment of the invention, a step of cold rolling of at least 7% and preferably at least 9% is carried out before performing a controlled stretching with a permanent set of 1 to 3%.
- Artificial aging is carried out, by heating at a temperature of between 130 and 170° C. and preferably between 150 and 160° C. for 5 to 100 hours and preferably for 10 to 40 hours so as to achieve a yield strength of Rp0.2 near the peak yield strength of Rp0.2.
- It is known that, for alloys with age hardening such as Al—Cu—Li alloys, the yield strength increases with the artificial aging time at a given temperature to a maximum value called the hardening peak or “peak”, then decreases with the aging time. In the context of this invention, the term aging curve will refer to the change in the yield strength as a function of the equivalent aging time at 155° C. An example of an aging curve is provided in
FIG. 1 . In the context of this invention, it is determined whether a point N on the aging curve, with an equivalent time at 155° C. tN and a yield strength of Rp0.2 (N) is close to the peak by determining the slope PN of the tangent to the aging curve at point N. In the context of this invention, the yield strength of a point N on the aging curve is considered to be close to the peak yield strength if the absolute value of the slope PN is at most 3 MPa/h. As shown inFIG. 1 , an under-aged temper is a temper for which PN is positive and an over-aged temper is a temper for which PN is negative. - To obtain a value close to PN, for a point N on the curve in an under-aged temper, the slope of the line passing through point N and through the preceding point N−1, obtained for a period tN-1<tN and having a yield strength Rp0.2 (N-1), can be determined; we thus have PN≈(Rp0.2 (N)−Rp0.2 (N-1))/(tN−tN-1). In theory, the exact value of PN is obtained when tN-1 tends toward tN. However, if the difference tN−tN-1 is small, the variation in the yield strength risks being insignificant and the value imprecise. The present inventors have noted that a satisfactory approximation of PN is generally obtained when the difference tN−tN-1 is between 2 and 15 hours and is preferably on the order of 3 hours.
- The equivalent time ti at 155° C. is defined by the formula:
- where T (in Kelvin) is the instantaneous metal treatment temperature, which changes with time t (in hours), and Tref is a reference temperature set at 428 K. ti is expressed in hours. The constant Q/R=16400 K is derived from the activation energy for the diffusion of Cu, for which the value Q=136100 J/mol has been used.
- The yield strength close to the peak yield strength is typically equal to at least 90%, generally even equal to fat least 95% and frequently at least 97% of the peak yield strength Rp0.2. The maximum peak yield strength can be obtained by varying the time and temperature parameters of the aging. The peak yield strength is generally considered to bed satisfactory when the aging time is varied between 10 and 70 h for a temperature of 155° C. after a stretching of 3.5%.
- In general, for Al—Cu—Li alloys, the clearly under-aged tempers correspond to compromises between the static mechanical strength (Rp0.2, Rm) and the damage tolerance (toughness, fatigue crack propagation resistance) that are better than at the peak and especially beyond the peak. However, the present inventors have noted that a near-peak under-aged temper may enable a beneficial damage tolerance to be obtained, while also improving the performances in terms of corrosion resistance and thermal stability.
- In addition, the use of a near-peak under-aged temper can enable the robustness of the industrial process to be improved: a variation in the aging conditions leads to a low variation in the properties obtained.
- It is thus advantageous to carry out a near-peak under-aging, i.e. an under-aging with time and temperature conditions equivalent to those of a point N on the aging curve at 155° C. so that the tangent to the aging curve at this point has a slope PN, expressed in MPa/h, so that 0<PN≦3 and preferably 0.2<PN≦2.5.
- Products according to the present invention can advantageously be used for example, in structural elements, in particular for airplanes. The use of a structural element incorporating at least one product according to the present invention and/or manufactured from such a product is advantageous, in particular for aeronautical construction. Products according to the present invention are particularly advantageous in the production of products machined from solids, such as in particular underwing or upper wing elements of which the skin and stringers are obtained from the same starting material, spars and ribs, as well as any other use in which these properties might be advantageous.
- These aspects, as well as others of the invention, are explained in greater detail in the following illustrative and non-limiting examples.
- In this example, a plurality of slabs with dimensions 2000×380×120 mm of which the composition is provided in table 1 were cast.
TABLE 1 Composition in weight % and density of Al—Cu—Li alloys cast in plate form. (Ref: reference; Inv: invention). Density Si Fe Cu Mn Mg Zn Ag Li Zr (g/ cm 3)1 0.012 0.022 3.54 0.38 0.32 — 0.24 0.89 0.10 2,706 (Ref) 2 0.012 0.023 3.53 0.38 0.32 — — 0.91 0.10 2,699 (Ref) 3 0.012 0.032 3.53 0.38 0.67 — 0.25 0.93 0.10 2,698 (Inv) 4 0.011 0.022 3.5 0.38 0.67 — — 0.94 0.10 2,692 (Inv) 5 0.078 0.088 3.52 0.38 0.34 — 0.25 0.91 0.10 2,705 (Ref) 6 0.015 0.029 3.50 0.39 0.31 0.39 0.24 0.95 0.10 2,707 (Ref)
Ti: target 0.02% by weight foralloys 1 to 6
- The slabs were homogenized at around 500° C. for around 12 hours, then cut and scalped so as to obtain parts with dimensions of 400×335×90 mm. The parts were hot rolled to obtain plates with a thickness of 20 mm. The plates were solution treated at 505+/−2° C. for 1 h, quenched with water at 75° C. so as to obtain a cooling rate of around 18° C./s and thus simulate the properties obtained at half-thickness in a plate with a thickness of 80 mm. The plates were then stretched with a permanent elongation of 3.5%.
- The plates were subjected to artificial aging for between 10 h and 50 h at 155° C. Samples were taken at half-thickness in order to measure the static mechanical tensile properties as well as the toughness KQ. The test pieces used for measuring toughness had a width W=25 mm and a thickness B=12.5 mm. In general, the values of KQ obtained from this type of test piece are smaller than those obtained from test pieces having a greater thickness and width. Two measurements, obtained from test pieces with a width W=40 mm and a thickness B=20 mm, confirm this tendency. It may be believed that measurements obtained from even wider test pieces enabling valid measurements of K1C to be obtained would also be higher than the measurements obtained with the test pieces with a width W=25 mm and a thickness B=12.5 mm.
- The results obtained are presented in table 2.
TABLE 2 Mechanical properties obtained for the different plates. Aging time in Evaluation hours KQ of the at Rp0.2 L Rm L A L (MPa.m1/2) slope PN Alloy 155° C. (Mpa) (Mpa) (%) L-T (MPa/h) 1 0 302.6 392.8 15.6 39.4 14 481.4 519.8 13.2 51.2 12.8 18 501.1 538.6 14.3 47.7 4.9 18 48.5* 23 501.2 536.4 13.9 46.6 0.0 36 509.6 544.8 13.4 45.8 0.6 2 0 300.6 393.6 15.5 30.7 14 442.2 489.9 14.2 44.0 10.1 18 465.7 507.5 13.8 48.4 5.9 23 474.0 513.0 13.0 46.2 1.7 36 486.6 523.7 12.0 47.2 1.0 3 0 358.8 455.8 18.0 — 14 437.0 503.6 15.5 46.1 5.6 18 488.4 532.1 13.2 44.4 12.9 23 502.7 540.7 14.3 48.2 2.8 23 53.6* 36 534.5 561.7 11.7 45.0 2.4 40 535.5 563.7 12.5 43.6 0.2 4 0 361.6 449.8 14.2 34.1 14 408.7 487.9 15.6 41.3 3.4 18 452.3 506.1 13.3 48.2 10.9 23 469.6 515.2 12.8 45.5 3.5 36 509.2 539.2 10.3 47.2 3.0 5 18 498.3 531.3 10.9 35.8 6 0 310.3 403.9 15.5 36.3 14 512.5 549.2 12.7 41.2 14.4 18 521.3 557.1 12.1 40.9 2.2 23 526.3 561.0 11.7 39.8 1.0
*test piece with width W = 40 mm and thickness B = 20 mm.
-
FIG. 2 shows the compromises in properties obtained for samples having a slope PN of between 0 and 3 and the measurements of toughness obtained with samples having a width W=25 mm and a thickness B=12.5 mm. The products according to the invention have a significantly improved compromise in properties over reference samples. - In this example, a plurality of slabs with a thickness of 406 mm of which the composition is provided in table 3 were cast.
TABLE 3 Composition in weight % and density of Al—Cu—Li alloys cast in plate form. Density Alloy Si Fe Cu Mn Mg Zn Ag Li Zr (g/cm3) 8 2050 0.03 0.06 3.51 0.41 0.3 0.02 0.37 0.84 0.09 2,713 (Ref) 211183 9 2195 0.03 0.04 4.2 0.4 0.35 1.06 0.11 2,700 (Ref) 176472 10 2195 0.03 0.05 3.87 0.02 0.31 0.01 0.35 1.06 0.11 2,695 (Ref) 271257 - The slabs were homogenized, then scalped. After homogenization, the slabs were hot rolled in order to obtain plates with a thickness of 50 mm. The plates were solution treated, quenched with cold water and stretched with a permanent elongation of between 3.5% and 4.5%
- The plates were then subjected to aging for between 10 h and 50 h at 155° C. Samples were obtained at half-thickness in order to measure the static mechanical tensile properties as well as the toughness KQ. The test pieces used to measure the toughness had a width W=80 mm and a thickness B=−40 mm. The validity criteria of K1C were satisfied for certain samples. The results obtained are presented in table 4.
TABLE 4 Mechanical properties obtained for the different plates. Aging KQ. Evaluation time KQ (MPa of the at Rm Rp0.2 A (MPa.m1/2) m1/2) slope PN 155° C. MPa MPa (%) L-T T-L (MPa/h) 8 15 531 494 10.1 46.0 37.4 (K1C) (K1C) 18 534 498 10.0 46.1 35.7 1.2 (K1C) (K1C) 21 544 510 9.4 44.0 35.0 4 (K1C) (K1C) 24 543 508 10.4 44.2 35.4 −0.5 (K1C) (K1C) 9 20 628 605 7.4 23.4 25 630.5 608.5 7.5 22.3 0.7 30 628 606 6.0 22.9 −0.5 35 626 603 6.5 22.0 −0.6 10 0 410 311 55.5 10 568.5 529.5 36.8 21.8 15 593 562 30.4 6.5 20 594.5 562.5 20.0 0.1 30 587.5 557.5 27.0 −0.5 45 613.5 587.5 24.7 2 - In
FIG. 3 , points 8, 9 and 10 have been added toFIG. 2 (slope PN between 0 and 3), although they concern test pieces of different shapes for the measurement of KQ (K1C) so as to facilitate the comparison between the invention and the prior art. It is thus confirmed that the products according to the invention have an improved compromise in properties over the prior art. - In this example, a plurality of slabs with dimensions 2000×380×120 mm of which the composition is provided in table 5 were cast.
TABLE 5 Composition in weight % and density of Al—Cu—Li alloys cast in plate form. (Ref: reference; Inv: invention). Density Si Fe Cu Mn Mg Zn Ag Li Ti Zr (g/cm3) 11 0,035 0,059 3,56 0,35 0,32 — 0,25 0,90 0,03 0,11 2,706 (Ref) 12 0,035 0,058 3,66 0,35 0,68 — 0,25 0,89 0,02 0,12 2,702 (Inv) 13 0,036 0,059 3,57 0,34 1,16 — 0,25 0,86 0,02 0,12 2,697 (Ref) - The slabs were homogenized fat around 500° C. for around 12 hours, then cut and scalped so as to obtain parts with dimensions of 400×335×90 mm. The parts were hot rolled to obtain plates with a thickness of 20 mm. The plates were solution treated at 505+/−2° C. for 1 h, and quenched with cold water. The plates were then stretched with a permanent elongation of 3.5%.
- The plates were subjected to artificial aging for between 18 h and 72 h at 155° C. Samples were taken at half-thickness in order to measure the static mechanical tensile properties as well as the toughness KQ. The test pieces used for measuring toughness had a width W=25 mm and a thickness B=12.5 mm.
- The results obtained are presented in table 6.
TABLE 6 Mecahnical properties obtained for the different sheets. Aging time in Evaluation hours KQ of the at Rp0.2 L Rm L A L (MPa.m1/2) slope PN Alloy 155° C. (Mpa) (Mpa) (%) L-T (MPa/h) 11 18 512.8 543.2 13.2 54.7 36 521.4 550.4 12.2 50.7 0.5 72 520.4 549.5 11.8 48.5 0.0 12 18 492.0 535.9 13.0 65.9 23 528.8 558.5 11.2 6.7 36 548.1 573.4 11.1 56.9 1.5 40 555.7 579.7 10.8 56.6 1.9 72 566.8 588.1 11.0 49.2 0.3 13 18 409.1 496.7 18.6 61.2 36 427.7 504.1 17.2 60.9 1.0 72 502.2 537.5 13.3 53.4 2.1 -
FIG. 4 shows the compromises in properties obtained for samples having a slope PN of between 0 and 3 and the measurements of toughness obtained with samples having a width W=25 mm and a thickness B=12.5 mm. The products according to the invention have a significantly improved compromise in properties over reference samples. - In this examples thermal stability of products made of alloy 12 were compared for different aging conditions. Plates made of alloy 12 and manufactured according to the method described in example 3 until the artificial aging step excluded underwent artificial aging at 155° C. or at 143° C. for the increasing durations indicated in Table 7. Plates which were artificially aged 34 h at 143° C. or 40 h at 155° C. were subsequently thermally tested for 1000 hours at 85° C. Samples were taken at half-thickness in order to measure the static mechanical tensile properties before and after thermal exposure.
- Results are presented in Table 7. After aging 34 hours at 143° C., for which the slope PN was evaluated to 7.1 the plate does not exhibit satisfactory thermal stability. Thus after thermal exposure the tensile yield strength has increased 15% and elongation has decreased 13%. To the contrary, after aging 40 hours at 155° C., for which the slope PN is evaluated to 1.9 the plate exhibit a satisfactory thermal stability, with an evolution of those properties less than 5%.
TABLEAU 7 Mechanical properties obtained for plates made of alloy 12, before and after thermal exposure 1000 h at 85° C. Eval- uation Before thermal of After thermal exposure 1000 h at the exposure 1000 h at 85° C. slope 85° C. Aging Rp0,2 PN Rp0,2 Aging time L Rm L A L (MPa/ L Rm L A L temperature (hours) (Mpa) (Mpa) (%) h) (Mpa) (Mpa) (%) 155° C. 23 528,8 558,5 11,2 6,7 36 548,1 573,4 11,1 1,5 40 555,7 579,7 10,8 1,9 564,3 578,0 10,2 143° C. 20 368,0 472,7 17,2 24 381,7 479,3 16,1 3,4 34 452,7 516,0 13,5 7,1 521,7 565,3 11,7
Claims (20)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US12/820,495 US11111562B2 (en) | 2009-06-25 | 2010-06-22 | Aluminum-copper-lithium alloy with improved mechanical strength and toughness |
Applications Claiming Priority (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US22024909P | 2009-06-25 | 2009-06-25 | |
FR09/03096 | 2009-06-25 | ||
FR0903096 | 2009-06-25 | ||
FR0903096A FR2947282B1 (en) | 2009-06-25 | 2009-06-25 | LITHIUM COPPER ALUMINUM ALLOY WITH IMPROVED MECHANICAL RESISTANCE AND TENACITY |
US12/820,495 US11111562B2 (en) | 2009-06-25 | 2010-06-22 | Aluminum-copper-lithium alloy with improved mechanical strength and toughness |
Publications (3)
Publication Number | Publication Date |
---|---|
US20110030856A1 US20110030856A1 (en) | 2011-02-10 |
US20110209801A2 true US20110209801A2 (en) | 2011-09-01 |
US11111562B2 US11111562B2 (en) | 2021-09-07 |
Family
ID=41484286
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US12/820,495 Active 2031-05-11 US11111562B2 (en) | 2009-06-25 | 2010-06-22 | Aluminum-copper-lithium alloy with improved mechanical strength and toughness |
Country Status (8)
Country | Link |
---|---|
US (1) | US11111562B2 (en) |
EP (1) | EP2449142B1 (en) |
CN (1) | CN102459671B (en) |
BR (1) | BRPI1011757B1 (en) |
CA (1) | CA2765382C (en) |
DE (1) | DE10734173T8 (en) |
FR (1) | FR2947282B1 (en) |
WO (1) | WO2010149873A1 (en) |
Cited By (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2014162069A1 (en) * | 2013-04-03 | 2014-10-09 | Constellium France | Thin sheets made of an aluminium-copper-lithium alloy for producing airplane fuselages |
WO2014162068A1 (en) * | 2013-04-03 | 2014-10-09 | Constellium France | Aluminium-copper-lithium alloy sheets for producing aeroplane fuselages |
FR3014905A1 (en) * | 2013-12-13 | 2015-06-19 | Constellium France | ALUMINUM-COPPER-LITHIUM ALLOY PRODUCTS WITH IMPROVED FATIGUE PROPERTIES |
WO2016051099A1 (en) | 2014-10-03 | 2016-04-07 | Constellium Issoire | Isotropic aluminium-copper-lithium alloy sheets for producing aeroplane fuselages |
EP3012338A1 (en) | 2014-10-26 | 2016-04-27 | Kaiser Aluminum Fabricated Products, LLC | High strength, high formability, and low cost aluminum lithium alloys |
FR3088935A1 (en) | 2018-11-28 | 2020-05-29 | Irt Antoine De Saint Exupéry | METHOD FOR STABILIZING THE PROPERTIES OF AN ALUMINUM ALLOY PART, A PART OBTAINED BY SUCH A METHOD, AND ITS USE IN AN AIRCRAFT |
US10835942B2 (en) | 2016-08-26 | 2020-11-17 | Shape Corp. | Warm forming process and apparatus for transverse bending of an extruded aluminum beam to warm form a vehicle structural component |
US11072844B2 (en) | 2016-10-24 | 2021-07-27 | Shape Corp. | Multi-stage aluminum alloy forming and thermal processing method for the production of vehicle components |
Families Citing this family (17)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2011130180A1 (en) | 2010-04-12 | 2011-10-20 | Alcoa Inc. | 2xxx series aluminum lithium alloys having low strength differential |
US9347558B2 (en) | 2010-08-25 | 2016-05-24 | Spirit Aerosystems, Inc. | Wrought and cast aluminum alloy with improved resistance to mechanical property degradation |
FR2981365B1 (en) | 2011-10-14 | 2018-01-12 | Constellium Issoire | PROCESS FOR THE IMPROVED TRANSFORMATION OF AL-CU-LI ALLOY SHEET |
US9458528B2 (en) | 2012-05-09 | 2016-10-04 | Alcoa Inc. | 2xxx series aluminum lithium alloys |
US10266933B2 (en) | 2012-08-27 | 2019-04-23 | Spirit Aerosystems, Inc. | Aluminum-copper alloys with improved strength |
RU2560481C1 (en) * | 2014-07-01 | 2015-08-20 | Федеральное государственное унитарное предприятие "Всероссийский научно-исследовательский институт авиационных материалов" (ФГУП "ВИАМ") | Al-Cu-Li-INTERMETALLIDE-BASED ALLOY AND ARTICLES MADE THEREOF |
CN104762504A (en) * | 2015-03-23 | 2015-07-08 | 蚌埠南自仪表有限公司 | Fly ash aluminium-based composite material with good hear resistance and preparation method thereof |
CN104762513A (en) * | 2015-03-23 | 2015-07-08 | 蚌埠市鸿安精密机械有限公司 | Easily-processed fly ash aluminum-based composite material and preparation method thereof |
ES2642730T5 (en) | 2015-03-27 | 2021-06-09 | Fuchs Kg Otto | Ag-free Al-Cu-Mg-Li alloy |
EP3072984B2 (en) | 2015-03-27 | 2020-05-06 | Otto Fuchs KG | Al-cu-mg-li alloy and alloy product produced from same |
FR3044682B1 (en) * | 2015-12-04 | 2018-01-12 | Constellium Issoire | LITHIUM COPPER ALUMINUM ALLOY WITH IMPROVED MECHANICAL RESISTANCE AND TENACITY |
US20190233921A1 (en) * | 2018-02-01 | 2019-08-01 | Kaiser Aluminum Fabricated Products, Llc | Low Cost, Low Density, Substantially Ag-Free and Zn-Free Aluminum-Lithium Plate Alloy for Aerospace Application |
FR3080861B1 (en) * | 2018-05-02 | 2021-03-19 | Constellium Issoire | METHOD OF MANUFACTURING AN ALUMINUM COPPER LITHIUM ALLOY WITH IMPROVED COMPRESSION RESISTANCE AND TENACITY |
CN108754263A (en) * | 2018-07-30 | 2018-11-06 | 东北轻合金有限责任公司 | A kind of high intensity space flight aluminium lithium alloy proximate matter and preparation method thereof |
CN110512125B (en) * | 2019-08-30 | 2020-09-22 | 中国航发北京航空材料研究院 | Preparation method of diameter aluminum-lithium alloy wire for additive manufacturing |
CN111304503A (en) * | 2020-03-12 | 2020-06-19 | 江苏豪然喷射成形合金有限公司 | Low-density damage-resistant aluminum-lithium alloy for aircraft wheel and preparation method thereof |
CN115821132A (en) * | 2022-11-25 | 2023-03-21 | 江苏徐工工程机械研究院有限公司 | Aluminum alloy and preparation method thereof |
Citations (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4999061A (en) * | 1983-12-30 | 1991-03-12 | The Boeing Company | Low temperature underaging of lithium bearing alloys and method thereof |
US5018612A (en) * | 1988-11-21 | 1991-05-28 | Usui Kokusai Sangyo Kaisha Limited | Temperature-controlled fan fluid coupling |
US5032359A (en) * | 1987-08-10 | 1991-07-16 | Martin Marietta Corporation | Ultra high strength weldable aluminum-lithium alloys |
US5234662A (en) * | 1991-02-15 | 1993-08-10 | Reynolds Metals Company | Low density aluminum lithium alloy |
US5389165A (en) * | 1991-05-14 | 1995-02-14 | Reynolds Metals Company | Low density, high strength Al-Li alloy having high toughness at elevated temperatures |
US5455003A (en) * | 1988-08-18 | 1995-10-03 | Martin Marietta Corporation | Al-Cu-Li alloys with improved cryogenic fracture toughness |
US20040071586A1 (en) * | 1998-06-24 | 2004-04-15 | Rioja Roberto J. | Aluminum-copper-magnesium alloys having ancillary additions of lithium |
US20050006008A1 (en) * | 2003-05-28 | 2005-01-13 | Pechiney Rolled Products | New Al-Cu-Li-Mg-Ag-Mn-Zr alloy for use as structural members requiring high strength and high fracture toughness |
WO2009036953A1 (en) * | 2007-09-21 | 2009-03-26 | Aleris Aluminum Koblenz Gmbh | Al-cu-li alloy product suitable for aerospace application |
US20090142222A1 (en) * | 2007-12-04 | 2009-06-04 | Alcoa Inc. | Aluminum-copper-lithium alloys |
Family Cites Families (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1995032074A2 (en) * | 1994-05-25 | 1995-11-30 | Ashurst Corporation | Aluminum-scandium alloys and uses thereof |
CN1216167C (en) * | 2002-01-30 | 2005-08-24 | 北京航空航天大学 | High-strength Al alloy containing Li and its preparing process |
RU2415960C2 (en) * | 2005-06-06 | 2011-04-10 | Алкан Реналю | Aluminium-copper-lithium sheet with high crack resistance for aircraft fuselage |
CN101189353A (en) * | 2005-06-06 | 2008-05-28 | 爱尔康何纳吕公司 | High-strength aluminum-copper-lithium sheet metal for aircraft fuselages |
US7875133B2 (en) | 2008-04-18 | 2011-01-25 | United Technologies Corporation | Heat treatable L12 aluminum alloys |
-
2009
- 2009-06-25 FR FR0903096A patent/FR2947282B1/en active Active
-
2010
- 2010-06-22 DE DE10734173T patent/DE10734173T8/en active Active
- 2010-06-22 EP EP10734173.7A patent/EP2449142B1/en active Active
- 2010-06-22 CN CN201080028657.9A patent/CN102459671B/en active Active
- 2010-06-22 WO PCT/FR2010/000455 patent/WO2010149873A1/en active Application Filing
- 2010-06-22 CA CA2765382A patent/CA2765382C/en active Active
- 2010-06-22 US US12/820,495 patent/US11111562B2/en active Active
- 2010-06-22 BR BRPI1011757-1A patent/BRPI1011757B1/en active IP Right Grant
Patent Citations (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4999061A (en) * | 1983-12-30 | 1991-03-12 | The Boeing Company | Low temperature underaging of lithium bearing alloys and method thereof |
US5032359A (en) * | 1987-08-10 | 1991-07-16 | Martin Marietta Corporation | Ultra high strength weldable aluminum-lithium alloys |
US5455003A (en) * | 1988-08-18 | 1995-10-03 | Martin Marietta Corporation | Al-Cu-Li alloys with improved cryogenic fracture toughness |
US5018612A (en) * | 1988-11-21 | 1991-05-28 | Usui Kokusai Sangyo Kaisha Limited | Temperature-controlled fan fluid coupling |
US5234662A (en) * | 1991-02-15 | 1993-08-10 | Reynolds Metals Company | Low density aluminum lithium alloy |
US5389165A (en) * | 1991-05-14 | 1995-02-14 | Reynolds Metals Company | Low density, high strength Al-Li alloy having high toughness at elevated temperatures |
US20040071586A1 (en) * | 1998-06-24 | 2004-04-15 | Rioja Roberto J. | Aluminum-copper-magnesium alloys having ancillary additions of lithium |
US7438772B2 (en) * | 1998-06-24 | 2008-10-21 | Alcoa Inc. | Aluminum-copper-magnesium alloys having ancillary additions of lithium |
US20050006008A1 (en) * | 2003-05-28 | 2005-01-13 | Pechiney Rolled Products | New Al-Cu-Li-Mg-Ag-Mn-Zr alloy for use as structural members requiring high strength and high fracture toughness |
US7229509B2 (en) * | 2003-05-28 | 2007-06-12 | Alcan Rolled Products Ravenswood, Llc | Al-Cu-Li-Mg-Ag-Mn-Zr alloy for use as structural members requiring high strength and high fracture toughness |
WO2009036953A1 (en) * | 2007-09-21 | 2009-03-26 | Aleris Aluminum Koblenz Gmbh | Al-cu-li alloy product suitable for aerospace application |
US20090142222A1 (en) * | 2007-12-04 | 2009-06-04 | Alcoa Inc. | Aluminum-copper-lithium alloys |
Cited By (19)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN105102647A (en) * | 2013-04-03 | 2015-11-25 | 伊苏瓦尔肯联铝业 | Aluminium-copper-lithium alloy sheets for producing aeroplane fuselages |
WO2014162068A1 (en) * | 2013-04-03 | 2014-10-09 | Constellium France | Aluminium-copper-lithium alloy sheets for producing aeroplane fuselages |
FR3004196A1 (en) * | 2013-04-03 | 2014-10-10 | Constellium France | ALUMINUM-COPPER-LITHIUM ALLOY SHEETS FOR THE MANUFACTURE OF AIRCRAFT FUSELAGES. |
FR3004197A1 (en) * | 2013-04-03 | 2014-10-10 | Constellium France | THIN ALUMINUM-COPPER-LITHIUM ALLOY SHEETS FOR THE MANUFACTURE OF AIRCRAFT FUSELAGES. |
WO2014162069A1 (en) * | 2013-04-03 | 2014-10-09 | Constellium France | Thin sheets made of an aluminium-copper-lithium alloy for producing airplane fuselages |
US10501835B2 (en) | 2013-04-03 | 2019-12-10 | Constellium Issoire | Thin sheets made of an aluminium-copper-lithium alloy for producing airplane fuselages |
FR3014905A1 (en) * | 2013-12-13 | 2015-06-19 | Constellium France | ALUMINUM-COPPER-LITHIUM ALLOY PRODUCTS WITH IMPROVED FATIGUE PROPERTIES |
WO2015086922A3 (en) * | 2013-12-13 | 2015-08-27 | Constellium France | Method for manufacturing products made of aluminium-copper-lithium alloy with improved fatigue properties, and distributor for this method |
WO2015086921A3 (en) * | 2013-12-13 | 2015-08-20 | Constellium France | Products made of aluminium-copper-lithium alloy with improved fatigue properties |
US10689739B2 (en) | 2013-12-13 | 2020-06-23 | Constellium Issoire | Aluminium-copper-lithium alloy products with improved fatigue properties |
WO2016051099A1 (en) | 2014-10-03 | 2016-04-07 | Constellium Issoire | Isotropic aluminium-copper-lithium alloy sheets for producing aeroplane fuselages |
FR3026747A1 (en) * | 2014-10-03 | 2016-04-08 | Constellium France | ALUMINUM-COPPER-LITHIUM ALLOY ISOTROPES FOR THE MANUFACTURE OF AIRCRAFT FUSELAGES |
US11174535B2 (en) | 2014-10-03 | 2021-11-16 | Constellium Issoire | Isotropic plates made from aluminum-copper-lithium alloy for manufacturing aircraft fuselages |
EP3012338A1 (en) | 2014-10-26 | 2016-04-27 | Kaiser Aluminum Fabricated Products, LLC | High strength, high formability, and low cost aluminum lithium alloys |
US10253404B2 (en) | 2014-10-26 | 2019-04-09 | Kaiser Aluminum Fabricated Products, Llc | High strength, high formability, and low cost aluminum-lithium alloys |
US10835942B2 (en) | 2016-08-26 | 2020-11-17 | Shape Corp. | Warm forming process and apparatus for transverse bending of an extruded aluminum beam to warm form a vehicle structural component |
US11072844B2 (en) | 2016-10-24 | 2021-07-27 | Shape Corp. | Multi-stage aluminum alloy forming and thermal processing method for the production of vehicle components |
FR3088935A1 (en) | 2018-11-28 | 2020-05-29 | Irt Antoine De Saint Exupéry | METHOD FOR STABILIZING THE PROPERTIES OF AN ALUMINUM ALLOY PART, A PART OBTAINED BY SUCH A METHOD, AND ITS USE IN AN AIRCRAFT |
WO2020109464A1 (en) | 2018-11-28 | 2020-06-04 | Irt Antoine De Saint Exupéry | Method for stabilizing the properties of an aluminum alloy part, part obtained by such a method and use thereof in an aircraft |
Also Published As
Publication number | Publication date |
---|---|
FR2947282B1 (en) | 2011-08-05 |
CN102459671A (en) | 2012-05-16 |
CA2765382A1 (en) | 2010-12-29 |
FR2947282A1 (en) | 2010-12-31 |
CA2765382C (en) | 2018-08-07 |
EP2449142A1 (en) | 2012-05-09 |
BRPI1011757A2 (en) | 2018-03-06 |
EP2449142B1 (en) | 2017-05-03 |
BRPI1011757B1 (en) | 2019-04-09 |
US20110030856A1 (en) | 2011-02-10 |
DE10734173T1 (en) | 2012-12-06 |
US11111562B2 (en) | 2021-09-07 |
WO2010149873A1 (en) | 2010-12-29 |
CN102459671B (en) | 2014-03-19 |
DE10734173T8 (en) | 2013-04-25 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US11111562B2 (en) | Aluminum-copper-lithium alloy with improved mechanical strength and toughness | |
US20120152415A1 (en) | Aluminum copper lithium alloy with improved resistance under compression and fracture toughness | |
US20190136356A1 (en) | Aluminium-copper-lithium products | |
US20120291925A1 (en) | Aluminum magnesium lithium alloy with improved fracture toughness | |
EP3649268B1 (en) | Al- zn-cu-mg alloys and their manufacturing process | |
US7744704B2 (en) | High fracture toughness aluminum-copper-lithium sheet or light-gauge plate suitable for use in a fuselage panel | |
EP1861516B2 (en) | Al-zn-cu-mg aluminum base alloys and methods of manufacture and use | |
US11472532B2 (en) | Extrados structural element made from an aluminium copper lithium alloy | |
US9945010B2 (en) | Aluminum-copper-lithium alloy with improved impact resistance | |
EP3026136A1 (en) | Aluminum alloy products having improved property combinations and method for artificially aging same | |
US20170292180A1 (en) | Wrought product made of a magnesium-lithium-aluminum alloy | |
US10196722B2 (en) | Method for manufacturing a structural element having a variable thickness for aircraft production | |
EP3899075B1 (en) | Al- zn-cu-mg alloys and their manufacturing process | |
US20110278397A1 (en) | Aluminum-copper-lithium alloy for a lower wing skin element | |
US20180363114A1 (en) | Aluminum copper lithium alloy with improved mechanical strength and toughness | |
US20160060741A1 (en) | Aluminium-copper-lithium alloy sheets for producing aeroplane fuselages | |
US20050150578A1 (en) | Metallurgical product and structure member for aircraft made of Al-Zn-Cu-Mg alloy | |
US20240287665A1 (en) | Aluminum-copper-lithium alloy products | |
US20210310108A1 (en) | Aluminum-copper-lithium alloy having improved compressive strength and improved toughness | |
CN112105752B (en) | Method for producing aluminum-copper-lithium alloys with improved compressive strength and improved toughness |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: ALCAN RHENALU, FRANCE Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:WARNER, TIMOTHY;SIGLI, CHRISTOPHER;GASQUERES, CEDRIC;AND OTHERS;SIGNING DATES FROM 20100622 TO 20100719;REEL/FRAME:024748/0351 |
|
AS | Assignment |
Owner name: CONSTELLIUM FRANCE, FRANCE Free format text: CHANGE OF NAME;ASSIGNOR:ALCAN RHENALU;REEL/FRAME:027489/0240 Effective date: 20110503 |
|
AS | Assignment |
Owner name: CONSTELLIUM ISSOIRE, FRANCE Free format text: CHANGE OF NAME;ASSIGNOR:CONSTELLIUM FRANCE SAS;REEL/FRAME:040423/0118 Effective date: 20150407 |
|
AS | Assignment |
Owner name: CONSTELLIUM ISSOIRE, FRANCE Free format text: CORRECTIVE ASSIGNMENT TO CORRECT THE CONVEYING PARTY PREVIOUSLY RECORDED AT REEL: 040423 FRAME: 0118. ASSIGNOR(S) HEREBY CONFIRMS THE CHANGE OF NAME;ASSIGNOR:CONSTELLIUM FRANCE;REEL/FRAME:045948/0577 Effective date: 20150407 |
|
STPP | Information on status: patent application and granting procedure in general |
Free format text: DOCKETED NEW CASE - READY FOR EXAMINATION |
|
STPP | Information on status: patent application and granting procedure in general |
Free format text: NON FINAL ACTION MAILED |
|
STPP | Information on status: patent application and granting procedure in general |
Free format text: FINAL REJECTION MAILED |
|
STCV | Information on status: appeal procedure |
Free format text: APPEAL BRIEF (OR SUPPLEMENTAL BRIEF) ENTERED AND FORWARDED TO EXAMINER |
|
STPP | Information on status: patent application and granting procedure in general |
Free format text: NOTICE OF ALLOWANCE MAILED -- APPLICATION RECEIVED IN OFFICE OF PUBLICATIONS |
|
STPP | Information on status: patent application and granting procedure in general |
Free format text: PUBLICATIONS -- ISSUE FEE PAYMENT VERIFIED |
|
STCF | Information on status: patent grant |
Free format text: PATENTED CASE |