CN107075623A - The method for preparing magnesium lithium-aluminium alloy product - Google Patents
The method for preparing magnesium lithium-aluminium alloy product Download PDFInfo
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- CN107075623A CN107075623A CN201580052804.9A CN201580052804A CN107075623A CN 107075623 A CN107075623 A CN 107075623A CN 201580052804 A CN201580052804 A CN 201580052804A CN 107075623 A CN107075623 A CN 107075623A
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- 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
- C22F1/047—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 magnesium as the next major constituent
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- 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
- C22C21/06—Alloys based on aluminium with magnesium as the next major constituent
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- 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
- C22C21/06—Alloys based on aluminium with magnesium as the next major constituent
- C22C21/08—Alloys based on aluminium with magnesium as the next major constituent with silicon
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- 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
- C22F1/002—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working by rapid cooling or quenching; cooling agents used therefor
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Abstract
The present invention relates to the method for preparing wrought, wherein：(a) aluminum alloy composition for as-cast form of casting, the aluminium alloy has the consisting of in terms of weight %：Mg:4.0‑5.0、Li:1.0‑1.8、Zr:0.05‑0.15、Mn≤0.6、Ag:≤0.5、Fe:≤0.1、Ti:<0.15、Si:≤ 0.05, each≤0.05 and summation≤0.15, remaining is aluminium to other elements；(b) optionally, the as-cast form is homogenized；(c) by the as-cast form thermal deformation to obtain thermal deformation product；(d) optionally, by the thermal deformation product at 360 DEG C to 460 DEG C, solution treatment 15 minutes to 8 hours at a temperature of preferably 380 DEG C to 420 DEG C；(e) the thermal deformation product is quenched；(f) optionally, the product of the thermal deformation and quenching is aligned or flattened；(g) product by the deformation and quenching is tempered；(h) the product cold deformation that will be deformed and be tempered under controlled conditions, to obtain 1 to 10%, preferably 2 to 6%, more preferably 3 to 5% permanent cold deformation.The invention further relates to can the wrought that obtains of the method according to the invention and the wrought be used to produce the purposes of aircraft structural element.
Description
Invention field
The present invention relates to the method for preparing aluminium-wrought made from magnesium-lithium alloy, more specifically, preparing has performance
Improvement trade off, the yield strength (limite d' é lasticit é en traction) of particularly described product is between toughness
The compromise product of improvement method.The invention further relates to product obtained by the preparation method and application thereof, the production
Product are used in particular for aerospace structure.
Background technology
Develop wrought made from aluminium alloy and be used in particular for the high intensity of aircraft industry and aerospace industry to produce
Part.
Aluminium alloy containing lithium is very meaningful in this respect, because often adding the lithium of a percentage by weight, lithium can be by aluminium
Density reduction by 3%, and by modulus of elasticity increase by 6%.Especially, at the same the aluminium alloy comprising magnesium and lithium can reach it is especially low
Density, therefore be widely studied.
Patent GB 1,172,736 is disclosed comprising 4 to 7% Mg, 1.5-2.6%Li, 0.2-1% in terms of weight %
Mn and/or 0.05-0.3%Zr, the alloy that remaining is aluminium.The alloy is used to manufacturing with high mechanical properties, good corrosion-resistant
The product of property, low-density and high elastic modulus.The product passes through including optional quenching and then the method for being tempered (revenu)
Obtain.For example, the product of the method from GB 1,172,736 has about 440MPa to about 490MPa tensile strength (r é
Sistance à la rupture), about 270MPa to about 340MPa yield strength and about 5-8% elongation at break.
International application WO 92/03583 describes the alloy for aeronautic structure, and it has low-density and formula is
MgaLibZncAgdAlbal, wherein a is that 0.5 to 10%, b is that 0.5 to 3%, c is that 0.1 to 5%, d is 0.1 to 2% and bal tables
It is aluminium to show remaining.The document also discloses that obtaining the method for the alloy, it comprises the following steps：A) casting has above-mentioned composition
Ingot blank, b) eliminate residual stress from the ingot blank by being heat-treated, c) homogenized by being heated and maintained at the temperature,
Then the ingot blank is cooled down, d) by the ingot blank hot pressing to its final thickness, e) by the product solution treatment of the compacting then
Quenching, f) stretches the product and g) is tempered the product by being heated and maintained at this temperature.
Patent US 5,431,876 discloses the ternary alloy three-partalloy group of aluminium lithium and magnesium or copper, and it includes at least one additive such as
Zirconium, chromium and/or manganese.Alloy is prepared according to method known to those skilled in the art, such as described known method include extruding,
Solution treatment, quenching, product stretching 2 to 7% and then is tempered.
Patent US 6,551,424 describes the method for preparing aluminium-rolled products made from magnesium-lithium alloy, the alloy tool
(in terms of weight %), Mg are constituted by following:3.0-6.0；Li:0.4-3.0；Zn is for up to 2.0；Mn is for up to 1.0；Ag is most
Up to 0.5；Fe is for up to 0.3；Si is for up to 0.3；Cu is for up to 0.3；0.02-0.5 be selected from Sc, Hf, Ti, V, Nd, Zr, Cr, Y,
Be element；Methods described includes the cold rolling of vertical and horizontal.
Patent US 6,461,566 describes the alloy with consisting of (in terms of weight %), Li:1.5-1.9；Mg:
4.1-6.0；Zn:0.1-1.5；Zr:0.05-0.3；Mn:0.01-0.8；H:0.9x10-5-4.5x 10-5It is selected from at least one
Be (0.001-0.2), Y (0.001-0.5) and Sc (0.01-0.3) element.
Patent application WO 2012/16072 describes wrought made from aluminium alloy, and the alloy has in terms of weight %
Consisting of, Mg:4.0-5.0、Li:1.0-1.6、Zr:0.05-0.15、Ti:0.01–0.15、Fe:0.02-0.2、Si:
0.02-0.2、Mn:≤0.5、Cr≤0.5、Ag:≤0.5、Cu≤0.5、Zn≤0.5、Sc<0.01st, other elements<0.05, remaining
For aluminium.Especially, the product is obtained according to the preparation method especially comprised the following steps successively：Cast undressed form
Alloy, then thermal deformation and optionally cold deformation, solution treatment quench the modified product, optionally cold deformation solution treatment
With the product of quenching, and the wrought is finally tempered at a temperature of less than 150 DEG C.Obtained advantageously for rolled products
Metallurgical state be T6 or T6X or T8 or T8X states, and advantageously for drawing product (product fil é), be
(in the case of press quenching) T5 or T5X or T6 or T6X or T8 or T8X states.
Aluminium-wrought made from magnesium-lithium alloy has low-density, therefore it especially has in extremely harsh aviation field
Profit.In order to select new product in such field, their performance must be obtained significantly relative to the performance of existing product
Improve, particularly their performance in static mechanical strength property (particularly stretching and compression yield strength, tensile strength) and
Compromise between damage tolerance performance (toughness, fatigue crack autgmentability), these properties are typically conflicting.
These alloys must also have enough corrosion resistances, to be shaped according to usual way；And with low
Residual stress, so that it can be processed without obvious distortion during the machining.
Accordingly, it would be desirable to aluminium-wrought made from magnesium-lithium alloy, it is low close that there is the property relative to known product to have for it
Degree and improved performance, the particularly compromise aspect between static mechanical strength performance and damage tolerance performance.Especially,
On damage tolerance performance, wrought must have high tenacity and low layering tendentiousness.In addition, this product allows for root
Obtained according to reliable, economical and easily adaptation conventional production lines manufacture methods.
Goal of the invention
First purpose of the present invention is the method for preparing wrought, wherein：
(a) aluminium alloy of (couler) undressed form is cast, the aluminium alloy has the consisting of in terms of weight %：
Mg:4.0-5.0、Li:1.0-1.8、Zr:0.05-0.15、Mn:≤0.6、Ag:≤0.5、Fe:≤0.1、Ti:<0.15、Si:≤
0.05th, each≤0.05 and summation≤0.15, remaining is aluminium to other elements；
(b) optionally, the undressed form is homogenized；
(c) by the undressed form thermal deformation to obtain thermal deformation product；
(d) optionally, by the thermal deformation product at 360 DEG C to 460 DEG C, solid solution at a temperature of preferably 380 DEG C to 420 DEG C
Processing 15 minutes to 8 hours；
(e) the thermal deformation product is quenched；
(f) optionally, it will deform and the product of quenching aligned or flattened；
(g) product of thermal deformation and quenching is tempered；
(h) under controlled conditions by the thermal deformation product cold deformation of tempering, to obtain 1 to 10%, preferably 2 to 6%, it is more excellent
Select 3 to 5% and more preferably 4 to 5% permanent cold deformation.
Other purposes of the present invention are the use of the wrought and the wrought of being capable of the method according to the invention acquisition
On the way, it is used to prepare aircraft structural element.
Brief description of the drawings
Fig. 1：Fuselage (fuselage) frame facet figure of embodiment 1
Fig. 2：For the thick band steels of 10mm, according to toughness KQ* (* is due to standard ASTM E399's by yield strength Rp0.2
Pmax/PQ≤ 1.10 discriminates, all KQValue is invalid)
Fig. 3：For the thick band steels of 10mm, according to the stress strength factor K corresponding to maximum, forcemax(according to standard ASTM
E399 estimate) yield strength Rp0.2
Embodiment
Unless otherwise indicated, on alloy chemical composition all signs with the weight of the gross weight meter based on alloy
Percentage is represented.For example, sign 1.4Cu means to be multiplied by 1.4 with the copper content that weight % is represented.The name of alloy meets Aluminum association
The regulation of meeting (AluminumAssociation), it is known to the skilled person.Density depends on constituting and is
By calculating rather than being determined by weighing measuring method.The numerical value is calculated according to the method for ABAL, and it is recorded in
" the 2-12 pages and 2-13 pages of Aluminum Standards and Data ".The definition of metallurgical state is listed in European standard
In EN515.
Stretch static mechanical characteristic, that is, tensile strength Rm, conventional yield intensity R in 0.2% elongationp0.2With
Elongation at break A%, is determined, the sampling of test and orientation are by standard according to standard NF EN ISO 6892-1 extension test
EN485-1 is defined.
Toughness is determined according to standard ASTM E399 toughness test K1c.Effective stress is shown according to effective Crack Extension
The curve of intensity factor is determined according to standard ASTM E399.Tested using sample CT8 (B=8mm, W=16mm).In root
According to standard ASTM E399, especially for discriminate Pmax/PQ≤ 1.10, KQIn the case that value is invalid, as a result also with Kmax(correspondence
In maximum, force PmaxStress intensity factor) provide.
During the toughness test K1c according to standard ASTM E399, the increase of product upper stress can show product pair
In the tendency of layering.Herein, " layering " (also referred to as " crackle layering " and/or " crackle separator ") mean with lead crack
Crackle in anterior orthogonal plane.The orientation of these planes corresponds to the pass connecing for the crystal grain of the non-recrystallization after forging deformation
Stitch the orientation of (joint).Low layering is the smaller mark of fragility of involved plane, and cause during fatigue is propagated or
The risk minimization that crackle deviates towards longitudinal direction under dull stress.
Unless otherwise indicated, applied code EN12258 definition.
In addition, herein, " structural detail " of mechanical realization (construction) or " element of structure " refers to so
Mechanical part, statically and/or dynamically mechanical property is especially important for the performance of structure for which, and leads to for which
Conventional fixed or progress Structure Calculation.They are usually that its failure can jeopardize the construction, user or other people is safe
Element.For airborne vehicle, these structural details particularly including composition fuselage (such as fuselage skin, fuselage reinforcement or side of a ship portion
(les raidisserus ou lisses de fuselage), bulkhead, fuselage ring (les cadre de fuselage),
Wing (such as upper limb or bottom wing covering), longeron or reinforcement, rib, spar, floor crossmember and seat rail) and especially by water
Tailplane and the element of hatch door that flat or vertical stabilizing member is constituted.
The method for preparing product of the present invention includes following consecutive steps：Liquid metal bath is prepared to obtain with specific group
Into Al-Mg-Li alloys, cast the alloy of undressed form, optionally homogenize the undressed shape so cast
Formula, undressed form described in thermal deformation optionally carries out independent solid solution to obtain thermal deformation product to such thermal deformation product
Processing, quenches to the thermal deformation product, the product of the deformation and quenching is optionally aligned/flatten, to the deformation and quenching
Product be tempered, and the product cold deformation to tempering in a controlled manner, to obtain 1 to 10%, preferably 2 to 6%, it is more excellent
Select 3 to 5% and more preferably 4 to 5% permanent cold deformation.
Therefore, preparation method includes the Al-Mg-Li alloys for casting undressed form first, and the alloy has with weight
Measure the composition of % meters：Mg:4.0-5.0、Li:1.0-1.8、Zr:0.05-0.15、Mn:≤0.6、Ag:≤0.5、Fe:≤0.1、
Ti:<0.15、Si:≤ 0.05, each≤0.05 and summation≤0.15, remaining is aluminium to other elements.Therefore, liquid gold is carried out
Category bath, then casts undressed form, and it typically is rolling ingot blank, drawing square billet or rough forging.
According to a favourable embodiment, the Mn contents counted using weight % of Al-Mg-Li alloys as 0.2 to 0.6%,
It is preferred that 0.35 to 0.5%, more preferably 0.35 to 0.45% and more preferably 0.35 to 0.40%.
With favourable Mn contents and the product as made from above-mentioned aluminium alloy have the static mechanical properties that especially improves with
And low layering tendency.
According to a favourable embodiment, the silver content that the aluminium alloy of undressed form has is less than or equal to 0.25 weight
% is measured, more preferably silver content is 0.05 weight % to 0.1 weight %.This element is particularly helpful to static mechanical properties.In addition,
According to a more favourable embodiment, the aluminium alloy of undressed form has less than 0.15 weight %, preferably lower than or equal to
0.12% total Ag and Cu contents.The anti intercrystalline corrosion of wrought can especially be improved by controlling the maximum level of both element summations
Property.
According to a special embodiment, the Zn content counted using weight % of undressed form is excellent as less than 0.04%
Choosing is less than or equal to 0.03%.In terms of this density for being limited in alloy and corrosion resistance of Zn content in above-mentioned particular alloy
Generate excellent result.
According to the embodiment of another (compatible) compatible with previous example, the aluminium alloy of undressed form
The Fe contents counted using weight % as less than 0.08%, preferably lower than or equal to 0.07%, more preferably less than or equal to 0.06%.
Inventor thinks that the Fe contents of minimum and the Si of possible minimum are conducive to improving the mechanical performance of alloy and be particularly
Fatigue behaviour.Especially, it is that 0.02 to 0.06 weight % and/or Si content is that 0.02 to 0.05 weight % can be obtained for Fe contents
Obtain excellent result.
The lithium content of product of the present invention is 1.0 to 1.8 weight %.According to a favourable embodiment, undressed form
Aluminium alloy the Li contents counted using weight % as less than 1.6%, preferably lower than or equal to 1.5%, more preferably less than or equal to
1.4%.Minimum lithium content is 1.1 weight % and preferably 1.2 weight % are favourable.Inventor is it has been observed that in some additions
Element in the presence of, the lithium content of restriction can significantly improve toughness, and this greatly compensate for the slight increase of density and quiet
The reduction of state mechanical performance.
According to a preferred embodiment, the Zr contents counted using weight % of the aluminium alloy of undressed form as 0.10 to
0.15%.Inventor actually observes, and this Zr contents can obtain the fiber knot for the static mechanical properties for being conducive to improving
The alloy of structure.
According to a favourable embodiment, the Mg contents counted using weight % of the aluminium alloy of undressed form as 4.5 to
4.9%.For the alloy according to the embodiment, especially with regard to static mechanical properties, excellent result is obtained.
According to a favourable embodiment, the Cr contents of product of the invention are less than 0.05 weight %, preferably smaller than
0.01 weight %.Especially, cause can be in casting process for the other elements of the Cr content cooperatives alloy of the present invention of this restriction
Limit the formation of first phase.
The Ti contents of the product of the present invention are less than 0.15 weight %, preferably 0.01 to 0.05 weight %.Especially, at this
In the specific alloy of invention, restricted T i contents are to prevent the formation of the first phase in casting process.On the other hand, cast in alloy
During, control Ti contents to control grainiess, particularly crystallite dimension to be probably favourable.
Some elements can be harmful to Al-Mg-Li alloys as described above, especially because alloy changes in deformation process,
Such as toxicity and/or rupture.It is therefore preferable that these elements are limited into extremely low level, i.e., less than 0.05 weight % or very
To less.In an advantageous embodiment, product of the invention has the 10ppm of maximum level Na, preferably 8ppm's
Na, and/or the 20ppm of maximum level Ca.According to a particularly advantageous embodiment, the aluminium alloy of undressed form is basic
Upper to be free of Sc, Be, Y, more preferably described undressed form includes these element combinations less than 0.01 weight %.
According to a particularly advantageous embodiment, the aluminium alloy of undressed form have in terms of weight % with the following group
Into：
Mg:4.0-5.0, preferably 4.5-4.9；
Li:1.1-1.6, preferably 1.2-1.5；
Zr:0.05-0.15, preferably 0.10-0.15；
Ti:<0.15, preferably 0.01-0.05；
Fe:0.02-0.1, preferably 0.02-0.06；
Si:0.02-0.05；
Mn:≤0.6；It is preferred that 0.2-0.6, more preferably 0.35-0.5；
Cr:<0.05, preferably<0.01；
Ag:≤0.5；It is preferred that≤0.25；More preferably≤0.1；
Sc:<0.01；
Other elements are each≤0.05 and its summation≤0.15；
Remaining is aluminium.Excellent result has been obtained using the alloy with this kind of composition.
Cast after undressed form step, manufacture method optionally includes the step homogenized to the undressed form
Suddenly, with reach 450 DEG C to 550 DEG C, preferably 480 DEG C to 520 DEG C temperature carry out 5 to 60 hours.The homogenize process can
To be realized by one or more steps (paliers).According to the preferred embodiment of the present invention, it is simply being heated
Thermal deformation is directly carried out afterwards, and is homogenized without any.
Then, generally by drawing, rolling and/or forging by undressed form thermal deformation, to obtain modified product.Should
Thermal deformation is more than 400 DEG C in inlet temperature and carried out advantageously at 420 DEG C to 450 DEG C.According to a favourable embodiment party
Case, thermal deformation is the deformation via the undressed form of drawing.
In the case of by rolling manufacture plate, 3mm product is less than for thickness, it may be necessary to carry out cold rolling step
(then it constitute the first optional step of cold deformation).It is favourable to carry out a step or some step intermediate heat-treatments, is generally existed
At 300 to 420 DEG C, carried out before or during cold rolling.
By the product of thermal deformation and optional cold deformation optionally at 360 to 460 DEG C, preferably 380 DEG C to 420 DEG C of temperature
It is lower to carry out individually (s é par é e) solution treatment 15 minutes to 8 hours.
Then the product of thermal deformation and optionally solution treatment is quenched.Quenched with water and/or with air.Favourable
It is to carry out quenching with air corrosion among crystalline grains are improved.In the case of drawing product, it is advantageous to carry out pressure and quench
Fire (or using drawing thermal quenching), preferably air pressure is quenched, and static mechanical properties can be especially improved using this kind of quenching.According to
Another embodiment, it can be also water pressure quenching.In the case of press quenching, product is used into drawing heat (chaleur
De filage) carry out solution treatment.
The product of thermal deformation and quenching can be optionally the step of section bar or sheet material are to be aligned or be flattened according to it.
Herein, " aligning/pressing " means the cold deformation step for not being permanently deformed or being permanently deformed less than 1%.
Then, the step of product of the thermal deformation, quenching and optional aligning/pressing is tempered.Advantageously, by
In one or several steps at a temperature of less than 150 DEG C, heated 5 to 100 hours preferably at a temperature of 70 DEG C to 140 DEG C
It is tempered.
Finally, can also by the thermal deformation product of tempering in a controlled manner cold deformation so as to obtain 1 to 10%, preferably 2 to
6%th, more preferably 3 to 5% and more preferably 4 to 5% permanent cold deformation.According to a favourable embodiment, permanent cold change
Shape is 2 to 4%.Especially, cold deformation can be carried out by stretching, compression and/or rolling.According to a preferred embodiment,
Cold deformation is carried out by stretching.Be all beyond one's expectations ground, shows really, when being carried out after tempering step, to such as
The cold deformation of the wrought of upper described composition in a controlled manner make it that static mechanical properties and damage tolerance can be obtained, is particularly
It is excellent compromise between toughness.Standard EN515 T9 states are particularly corresponding to for the metallurgical state that wrought is obtained.Root
According to a favourable embodiment, prepare the method for wrought in hot deformation step or --- if there is the step
Words --- do not include the cold deformation step of any permanent deformation for causing at least 1% between solution treatment and tempering step.
The content and transition parameters of selected composition, particularly Mg, Li and Mn (if Mn presence), particularly manufacture method
The combination of the order of step can be obtained advantageously with the compromise of completely special improvement performance, particularly mechanical strength and damage
It is compromise between tolerance limit, while it still has low-density and good corrosive nature.
The wrought of the present invention is preferably drawing product (such as section bar), rolled product (such as sheet material or slab) and/or forging
Product.
A further object of the invention is the wrought that can be obtained according to the above method, and advantageously, permanent cold deformation is big
In 4% this kind of cold deformation product.In fact, this product has completely new and special characteristic.
The wrought obtained by the method for the present invention, it is advantageous that permanent cold deformation is more than 4% this kind of product, especially
It is that there is at least one static mechanical strength selected from performance (i) to (iii) in the case where thickness is 0.5 to 15mm intermediate gauge
Can be with least one damage tolerance performance for being selected from performance (iv) to (v)：
(i) tensile strength Rm (L) >=440MPa, preferably Rm (L) >=445MPa, more preferably Rm (L) >=450MPa and more
It is preferred that Rm (L) >=465MPa；
(ii) yield strength Rp0.2 (L) >=360MPa；It is preferred that Rp0.2 (L) >=380MPa, more preferably Rp0.2 (L) >=
390MPa and more preferably Rp0.2 (L) >=400MPa；
(iii) yield strength Rp0.2 (TL) >=330MPa and preferred Rp0.2 (TL) >=340MPa and more preferably
Rp0.2(TL)≥370MPa；
(iv) the toughness K determined with width W=16mm and thickness=8mm sample CT8 according to standard ASTM E399Q(L-
T) >=20MPa √ m, preferably KQ(L-T)≥22MPa√m；
(v) maximum is corresponded to according to what standard ASTM E399 were determined with width W=16mm and thickness=8mm sample CT8
Power Pmax stress strength factor K max (L-T) >=20MPa √ m, preferably Kmax (L-T) >=25MPa √ m.
According to a preferred embodiment, the wrought that can be obtained by the method for the present invention thickness be 0.5 to
There are at least two static mechanical strength performances selected from performance (i) to (iii) and at least one choosing under 15mm intermediate gauge
From performance (iv) to (v) damage tolerance performance.
In addition, there is the wrought of the present invention smaller layering to be inclined to, wherein according to standard ASTME399 (sample CT8, B
=8mm, W=16mm) layering tendency is assessed on sample K1c break surface.
The drawing product of the present invention has particularly advantageous characteristic.Drawing product preferably has 0.5mm to 15mm thickness,
But it is more than 15mm with thickness, up to 50mm or even more than 100mm product can also have favourable performance.Drawing is produced
The thickness of product is according to standard EN2066：2001 definition：It is the generally rectangular of A and B that lateral cross section, which is divided into size,；Wherein A is always
Generally rectangular full-size, B is considered as generally rectangular thickness.Bottom is with the generally rectangular of full-size A.
The wrought of the present invention, which is advantageously used in, prepares aircraft structural element, particularly the structural detail of aircraft.Especially
Ground, aircraft structural element preferably is that fuselage skin, fuselage ring, fuselage reinforcement or longeron or wing cover, wing add
Strengthening tendons, rib or spar.It is for the use of these are explained in greater detail in following illustrative and non-limiting example and of the invention
Other side.
Embodiment
Embodiment 1
The Al-Mg-Li alloys of some undressed forms are cast, it is constituted provides in table 1.Alloy A and B are respectively provided with suitable
In the composition for the method for implementing the present invention.According to " the 2-12 pages and the 2-13 pages of Aluminum Standards and Data "
Described in Aluminum Association method calculate alloy A and B density be 2.55.
The density of composition and used Al-Mg-Li alloy of the table 1 in terms of weight %
A diameter of 358mm blank is carried out in undressed form.They are heated to 430-440 DEG C, then passes through compacting
Drawing thermal deformation is the profile form of the fuselage ring shown in Fig. 1.By the product of thus drawing with air hardening (press quenching).
Then they are carried out：
- for product of the end-state for T6：30h is carried out at 120 DEG C, two steps that 10h is then carried out at 100 DEG C are returned
Fire；
- for product of the end-state for T8：It is permanently deformed to the controlled of 3 or 5% (being respectively T8-3% and T8-5%)
Stretching, then carries out 30h at 120 DEG C, and 10h two steps tempering is then carried out at 100 DEG C；
- for product of the end-state for T9：30h is carried out at 120 DEG C, two steps that 10h is then carried out at 100 DEG C are returned
Fire, then carries out being permanently deformed to the controlled stretch of 3 or 5% (being respectively T9-3% and T9-5%).
Static mechanical properties (yield strength R by MPa in terms of of the test sample to determine themp0.2, the tension in terms of MPa
Intensity RmWith the elongation A in terms of %).
Acquired results are shown in table 2 below (direction L) and 3 (direction TL).These results are the fuselage rings to direction L
On 4 positions (position represented in Fig. 1 with a, b, c and d) sampling the average value that carries out for 4 times measures of through thickness sample,
And the average value of 2 measurements is carried out labeled as the through thickness sample of c 1 single position sample in Fig. 1 to direction TL.
The mechanical performance (direction L) of the products obtained therefrom of table 2
The mechanical performance (direction TL) of the products obtained therefrom of table 3
The maximum stress or tensile strength Rm and surrender that the mechanical performance of the product of T9 states, particularly product can be born are strong
Spend those performances that Rp0.2 (strain value of 0.2% plastic deformation) is significantly higher than T8 or T6 phase products in gamut.
Moreover, mechanical performance, particularly Rp0.2, strengthen (T6 with the increase of controlled stretch<T8-3%<T8-5%<T9-3%<
T9-5%).
Relative to the mechanical strength for the alloy (alloy A) that Mn contents are about 0.14 weight %, Mn contents are about 0.4 weight %
Al-Mg-Li alloys (alloy B) allow to significantly improve the mechanical strength (Rp0.2 and Rm) of alloy, particularly along direction
L mechanical strength.
Embodiment 2
The Al-Mg-Li alloys of some undressed forms are cast, it is constituted provides in table 1.Alloy A and B are respectively provided with suitable
In the composition for the method for implementing the present invention.
A diameter of 358mm blank is carried out in undressed form.They are heated to 430-440 DEG C, then passes through punching press
Drawing thermal deformation is the form of band steel (100mm x 10mm).By the product of thus drawing with air hardening (press quenching).So
They are carried out afterwards：
- for product of the end-state for T6：30h is carried out at 120 DEG C, two steps that 10h is then carried out at 100 DEG C are returned
Fire；
- for product of the end-state for T8：It is permanently deformed to the controlled of 3 or 5% (being respectively T8-3% and T8-5%)
Stretching, then carries out 30h at 120 DEG C, and 10h two steps tempering is then carried out at 100 DEG C；
- for product of the end-state for T9：30h is carried out at 120 DEG C, two steps that 10h is then carried out at 100 DEG C are returned
Fire, then carries out being permanently deformed to the controlled stretch of 3 or 5% (being respectively T9-3% and T9-5%).
Test diameter is static mechanical properties (yield strength by MPa in terms of of the 4mm cylindrical sample to determine them
Rp0.2, the tensile strength R in terms of MPamWith the elongation A in terms of %).
Acquired results are shown in table 4 below (direction L) and 5 (direction TL).
The mechanical performance (direction L) of the products obtained therefrom of table 4
The mechanical performance (direction TL) of the products obtained therefrom of table 5
The yield strength (strain value of 0.2% plastic deformation, Rp0.2) of the product of T9 states is significantly higher than T8 or T6
Those performances of phase product.Moreover, Rp0.2 strengthens (T6 with the increase of controlled stretch stress<T8-3%<T8-5%<
T9-3%<T9-5%).
Relative to the mechanical strength for the alloy (alloy A) that Mn contents are about 0.14 weight %, Mn contents are about 0.4 weight %
Al-Mg-Li alloys (alloy B) allow to significantly improve the mechanical strength (Rp0.2 and Rm) of alloy.
The toughness characteristics of product are to be tested according to standard ASTM E399 K1c.The test is sampled with intermediate gauge
Sample CT8 (B=8mm, W=16mm) carry out.According to standard ASTM E399, especially with respect to discriminate Pmax/PQ≤
1.10, KQValue be still invalid.Therefore, result is with Kmax(correspond to maximum, force PmaxStress intensity factor) represent.Knot
Fruit record is in table 6 and 7 and shows in figs 2 and 3 (being respectively sample L-T and T-L).These results are at least two values
Average value.
Result (the K in terms of MPa √ m for the toughness tested on the sample L-T of table 6maxAnd KQ)
Result (the K in terms of MPa √ m for the toughness tested on the sample T-L of table 7maxAnd KQ)
The product of the present invention has gratifying toughness, and unrelated with the Mn contents of alloy.
Fig. 2 is shown according to toughness KQ(due to discriminate Pmax/PQ≤ 1.10, all KQValue is invalid), the present embodiment
The yield strength Rp0.2 of product.Fig. 3 is shown according to the stress strength factor K for corresponding to maximum stressmaxThe embodiment
The yield strength Rp0.2 of product.
Static properties (particularly Rp0.2) and their toughness K of the T9 product at themQOr it corresponds to maximum, force
Stress strength factor KmaxBetween have it is good compromise.
According to 0 to 2 scoring, layering is quantified with semiquantitative way on above-mentioned sample K1c break surface：Score value 0=
There is no visible delamination, the low layerings of score value 1=, score value 2=is substantially layered (some layering plate/secondary crackles are visible in direction L).
Table 8 and 9 summarizes the scoring of specified different samples (being respectively sample L-T and T-L).
The sample L-T of table 8 layering evaluation (scoring)
The sample T-L of table 9 layering evaluation (scoring)
Product made from alloy B has lower layering than product made from alloy A.
Claims (13)
1. the method for wrought is prepared, wherein：
(a) aluminium alloy of undressed form is cast, the aluminium alloy has the consisting of in terms of weight %：Mg:4.0-5.0、
Li:1.0-1.8、Zr:0.05-0.15、Mn≤0.6、Ag:≤0.5、Fe:≤0.1、Ti:<0.15、Si:≤ 0.05, other elements
Each≤0.05 and summation≤0.15, remaining is aluminium；
(b) optionally, the undressed form is homogenized；
(c) by the undressed form thermal deformation to obtain thermal deformation product；
(d) optionally, by the thermal deformation product at 360 DEG C to 460 DEG C, solution treatment at a temperature of preferably 380 DEG C to 420 DEG C
15 minutes to 8 hours；
(e) the thermal deformation product is quenched；
(f) optionally, the product of thermal deformation and quenching is aligned or flattened；
(g) product of thermal deformation and quenching is tempered；
(h) under controlled conditions by the modified product cold deformation of tempering, with obtain 1 to 10%, preferably 2 to 6%, more preferably 3 to
5% permanent cold deformation.
2. the method for claim 1 wherein the deformation that the thermal deformation of step (c) is the undressed form of drawing.
3. the method for claim 1 or 2, the wherein thermal deformation of step (c) are more than 400 DEG C in initial temperature, preferably 420 DEG C extremely
Carried out at 450 DEG C.
4. the quenching of the method for any one of claims 1 to 3, wherein step (e) is press quenching.
5. the quenching of the method for any one of Claims 1-4, wherein step (e) is carried out with air.
6. in the method for any one of claim 1 to 5, wherein step (g) thermal deformation and quenching product tempering by
In one step or some steps at a temperature of less than 150 DEG C, 5 to 100 hours are heated preferably at 70 DEG C to 140 DEG C to carry out.
7. the Mn contents counted using weight % the method for claim 1 wherein the aluminium alloy of the undressed form is 0.2 to 0.6,
It is preferred that 0.35 to 0.5.
8. the Zn contents counted using weight % the method for claim 1 wherein the aluminium alloy of the undressed form as less than
0.04%, preferably lower than or equal to 0.03%.
9. the Fe contents counted using weight % the method for claim 1 wherein the aluminium alloy of the undressed form as less than
0.08%, preferably lower than or equal to 0.07%, more preferably less than or equal to 0.06%.
10. the Li contents counted using weight % the method for claim 1 wherein the aluminium alloy of the undressed form as less than
1.6%, preferably lower than or equal to 1.5%, more preferably less than or equal to 1.4%.
11. the wrought obtained according to the method for any one of claim 1 to 10.
12. the wrought of claim 11, has performance (i) into (iii) in the case where thickness is 0.5 to 15mm intermediate gauge
At least one static mechanical strength performance and performance (iv) are at least one of (v) damage tolerance：
(i) tensile strength Rm (L) >=440MPa, preferably Rm (L) >=445MPa and more preferably Rm (L) >=450MPa；
(ii) yield strength Rp0.2 (L) >=360MPa and preferred Rp0.2 (L) >=380MPa and more preferably Rp0.2 (L) >=
400MPa；
(iii) yield strength Rp0.2 (TL) >=330MPa and preferred Rp0.2 (TL) >=340MPa and more preferably Rp0.2
(TL)≥370MPa；
(iv) the toughness K determined with width W=16mm and thickness=8mm sample CT8 according to standard ASTM E399Q(L-T)≥
20MPa √ m, preferably KQ(L-T)≥22MPa√m；
(v) maximum, force is corresponded to according to what standard ASTM E399 were determined with width W=16mm and thickness=8mm sample CT8
Pmax stress strength factor K max (L-T) >=20MPa √ m, preferably Kmax (L-T) >=25MPa √ m.
13. the purposes of wrought obtained according to any one of claim 1 to 10 or claim 11 or 12, for making
Standby aircraft structural element, preferably fuselage skin, fuselage ring, fuselage reinforcement or longeron or wing cover, wing reinforcement,
Rib or spar.
Applications Claiming Priority (5)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR14/02186 | 2014-09-29 | ||
| FR14/02187 | 2014-09-29 | ||
| FR1402187A FR3026410B1 (en) | 2014-09-29 | 2014-09-29 | CORROYE PRODUCT ALLOY ALUMINUM MAGNESIUM LITHIUM |
| FR1402186A FR3026411B1 (en) | 2014-09-29 | 2014-09-29 | METHOD FOR MANUFACTURING LITHIUM MAGNESIUM ALUMINUM ALLOY PRODUCTS |
| PCT/FR2015/052581 WO2016051061A1 (en) | 2014-09-29 | 2015-09-29 | Method for manufacturing products made of magnesium-lithium-aluminum alloy |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN107075623A true CN107075623A (en) | 2017-08-18 |
Family
ID=54356641
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201580052804.9A Pending CN107075623A (en) | 2014-09-29 | 2015-09-29 | The method for preparing magnesium lithium-aluminium alloy product |
| CN201580052806.8A Pending CN106715735A (en) | 2014-09-29 | 2015-09-29 | Wrought product made of a magnesium-lithium-aluminum alloy |
Family Applications After (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201580052806.8A Pending CN106715735A (en) | 2014-09-29 | 2015-09-29 | Wrought product made of a magnesium-lithium-aluminum alloy |
Country Status (8)
| Country | Link |
|---|---|
| US (2) | US20170218493A1 (en) |
| EP (2) | EP3201370B1 (en) |
| JP (1) | JP2017532456A (en) |
| KR (1) | KR20170067810A (en) |
| CN (2) | CN107075623A (en) |
| BR (2) | BR112017006273B1 (en) |
| CA (2) | CA2960947A1 (en) |
| WO (2) | WO2016051061A1 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112105752A (en) * | 2018-05-02 | 2020-12-18 | 伊苏瓦尔肯联铝业 | Method for producing aluminum-copper-lithium alloys with improved compressive strength and improved toughness |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109890663B (en) | 2016-08-26 | 2023-04-14 | 形状集团 | Warm forming process and apparatus for transverse bending extrusion of aluminum beams to warm form vehicle structural members |
| FR3057476B1 (en) * | 2016-10-17 | 2018-10-12 | Constellium Issoire | ALUMINUM-MAGNESIUM-SCANDIUM ALLOY THIN SHEET FOR AEROSPATIAL APPLICATIONS |
| CN110114498A (en) | 2016-10-24 | 2019-08-09 | 形状集团 | Multistage aluminium alloy for producing vehicle part is formed and hot-working method |
| CA3134698A1 (en) * | 2019-04-05 | 2020-10-08 | Arconic Technologies Llc | Methods of cold forming aluminum lithium alloys |
| US20230002865A1 (en) * | 2019-12-17 | 2023-01-05 | Novelis, Inc. | Suppression of stress corrosion cracking in high magnesium alloys through the addition of calcium |
| CN112226656A (en) * | 2020-09-25 | 2021-01-15 | 西南铝业（集团）有限责任公司 | Production process of Al-Mg-Mn-Er aluminum alloy extruded product |
| CN112410691B (en) * | 2020-11-10 | 2021-12-24 | 中国航发北京航空材料研究院 | Annealing process of aluminum-lithium alloy material |
| CN114054531B (en) * | 2021-11-18 | 2024-09-20 | 西南铝业（集团）有限责任公司 | Extrusion method of high-uniformity 2196 aluminum-lithium alloy section bar |
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- 2015-09-29 CA CA2960942A patent/CA2960942A1/en not_active Abandoned
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- 2015-09-29 BR BR112017006131A patent/BR112017006131A2/en active Search and Examination
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- 2015-09-29 WO PCT/FR2015/052580 patent/WO2016051060A1/en active Application Filing
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- 2015-09-29 US US15/514,398 patent/US20170292180A1/en not_active Abandoned
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Also Published As
| Publication number | Publication date |
|---|---|
| CA2960942A1 (en) | 2016-04-07 |
| EP3201370A1 (en) | 2017-08-09 |
| EP3201370B1 (en) | 2020-04-15 |
| WO2016051061A1 (en) | 2016-04-07 |
| CN106715735A (en) | 2017-05-24 |
| BR112017006131A2 (en) | 2017-12-19 |
| JP2017532456A (en) | 2017-11-02 |
| US20170218493A1 (en) | 2017-08-03 |
| US20170292180A1 (en) | 2017-10-12 |
| BR112017006273A2 (en) | 2017-12-12 |
| EP3201371B1 (en) | 2021-04-28 |
| EP3201371A1 (en) | 2017-08-09 |
| CA2960947A1 (en) | 2016-04-07 |
| KR20170067810A (en) | 2017-06-16 |
| BR112017006273B1 (en) | 2021-06-08 |
| WO2016051060A1 (en) | 2016-04-07 |
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