Abstract: A rapidly solidified aluminum base lithium containing alloy is subjected to at least one overaging treatment and a plurality of rolling passes. Upon completion of the process, the alloy is comprised of grains having an ultrafine grain size. A predominant number of the grains have grain boundaries pinned by the precipitation of Al.sub.3 Zr phase. The alloy has an elongation greater than 500% at temperature above about 500.degree. C. and a strain rate above about 4.times.10.sup.-2 /s.

Abstract: Disclosed is a method of making lithium-containing aluminum base alloy extrusion having at least a section thereof having a low aspect ratio, the extrusions having improved properties in sections thereof having the low aspect ratio. The method comprises providing a body of a lithium-containing aluminum alloy, extruding a low aspect ratio extrusion section, the aspect ratio being in the range of 1 to 2.5, and maintaining the body in a temperature range of 400.degree. to 1000.degree. F. and at least a 4:1 extrusion reduction during said extrusion step, the extrusion section having tensile yield strength of at least 60 ksi and having an ultimate yield strength of at least 4.5 ksi greater than the tensile yield strength.

Abstract: An aluminum based alloy useful in aircraft and airframe structures which has low density and consists essentially of the following formula:Mg.sub.a Li.sub.b Zn.sub.c Ag.sub.d Al.sub.balwherein a ranges from 0.5 to 10%, b ranges from 0.5 to 3.0%, c ranges from 0.1 to 5.0%, d ranges from 0.1 to 2.0%, and bal indicates the balance of the alloy is aluminum, with the proviso that the total amount of alloying elements cannot exceed 12.0%, with the further proviso that when a ranges from 7.0 to 10.0%, b cannot exceed 2.5% and c cannot exceed 2.0%.

Abstract: An improved aluminum-silicon-copper alloy having a relatively high level of bismuth is provided which is particularly wear-resistant and sufficiently self-lubricating so as to be suitable for use in a wearing component even when poorly lubricated. The relatively high bismuth level within the alloy cooperates with the other elemental additions so as to provide a sufficiently low friction bearing surface (or self-lubricity), which significantly enhances the wear resistant properties of the alloy. In particular, the preferred aluminum alloy is suited for use in a socket plate which receives high strength steel bearing members within a compressor unit of an automobile air conditioning system. The improved aluminum alloy should minimize wear and alleviate galling of the socket plate during use. In addition, the improved aluminum alloy should have sufficient strength and ductility so as to permit swaging of the socket plate formed from the alloy around a balled end of the high strength steel bearing member.

Abstract: An improved aluminum-silicon alloy having relatively substantial additions of tin and bismuth is provided which is particularly wear-resistant and sufficiently self-lubricating so as to be suitable for use in a wearing component even when poorly lubricated. The relatively high tin and bismuth additions within the alloy cooperate with the other elemental additions so as to provide a sufficiently low friction bearing surface (or self-lubricity) which significantly enhances the wear resistant properties of the alloy. In particular, the preferred aluminum alloy is used to form a socket plate which receives high strength steel bearing members within a compressor unit of an automobile air conditioning system. The improved aluminum alloy minimizes wear and alleviates galling of the socket plate during use.

Abstract: A process for the manufacture of an aluminum alloy sheet from an aluminum alloy of the alumium-magnesium-manganese type which is believed to be substantially un-heat treatable. This process comprises the solution heat treatment of the alloy, quenching of the alloy, cold rolling of the alloy, an artificial aging of the alloy. Moreover, the period of time from the end of the quenching to the beginning of the artificial aging is not greater than about 10 minutes. The process can further comprise the homogenation, hot rolling, coiling, first cold rolling, annealing, and second cold rolling prior to the solution heat treatment of the alloy. The product can be effectively employed as a can stock.

Abstract: This invention relates to a metal alloy, comprised of two elements, a solute and a solvent, the solute having a maximum equilibrium solid solubility (at one atmosphere pressure) of less than 1 wt. -% in the solvent, the solvent and the solute dissolved therein forming a matrix phase, the matrix phase having a subgrain structure defined by subgrain boundaries and particles at intersections of the boundaries, the subgrains having an average size of less than 5 microns in diameter, and, within the subgrains a dispersion of particles which are finer than the particles at the subgrain boundaries, both types of particles being harder than the matrix phase.

Abstract: A heat resistant slide member for an internal combustion engine is a plastically worked member formed from a quenched and solidified aluminum alloy, with a metal flow line in a sliding portion thereof set in a sliding direction. The aluminum alloy contains at least one selected from the group consisting of Cr, Fe, Zr and Ti in an amount of 5% or more and 30% by weight or less and has an average diameter of precipitates and crystallizates therein of 50 .mu.m or less and a tensile strength at 300.degree. C. of 18 kg/mm.sup.2 or more.

Abstract: A rapidly solidified aluminum base alloy consists essentially of the formula Al.sub.bal Fe.sub.a Si.sub.b X.sub.c, wherein X is at least one element selected from the group consisting of W, Ta, Nb, "a" ranges from 3.0 to 7.1 at %, "b" ranges from 1.0 to 3.0 at %, "c" ranges from 0.25 to 1.25 at % and the balance is aluminum plus incidental impurities, with the provisos that the ratio [Fe+X]:Si ranges from abut 2.33:1 to 3.33:1 and that the ratio Fe:X ranges from abut 16:1 to 5:1. The alloy exhibits high strength, ductility and fracture toughness and is especially suited for use in high temperature structural applications such as gas turbine engines, missiles, airframes and landing wheels.

Abstract: Aluminium alloy and a method of making it, whereby the alloy contains Zr and from 0 to 1% of one or more of the elements Mg, Si, Ag, Ni and Cu, the balance being mainly Al, the alloy being made on the basis of a melt which contains 0.5 to 2% by weight of Zr and which has been cast into particles by being cooled with such a high velocity that the Zr mainly is present in a supersaturated solution. The particles are consolidated and the Zr is precipitated as finely distributed dispersoids after a heat treatment at 300.degree. to 450.degree. C., and the alloy has an electrical conductivity of at least 58% IACS and a 10% softening temperature of at least 400.degree. C. The consolidation may for instance be carried out by extrusion.

Abstract: An aluminum base alloy wrought product having an isotropic texture and a process for preparing the same is disclosed. The product has the ability to develop improved properties in the 45.degree. direction or more uniform properties throughout the thickness and in the short transverse direction in response to an aging treatment and is comprised of 0.2 to 5.0 wt. % Li, 0.05 to 6.0 wt. % Mg, at least 2.45 wt. % Cu, 0.1 to 1.0 wt. % Mn, 0.05 to 12 wt. % Zn, 0.5 wt. % max. Fe, 0.5 wt. % max. Si, the balance aluminum and incidental impurities. The product has imparted thereto, prior to a hot rolling step, a recrystallization effect to provide therein after hot rolling a metallurgical structure generally lacking intense work texture characteristics. After an aging step, the product has improved levels of properties in the 45.degree. direction or more uniform properties throughout the thickness and in the short transverse direction.

Abstract: An aluminum-lead bearing alloy in continuously cast strip form has a lead content in excess of 1% by volume, 4% by weight. The lead phase consists of uniformly distributed spherical particles no more than 25 microns in diameter, and the content of all other constituents other than aluminum totals not more than 10% by weight, the balance being aluminum. The alloy is used in engine bearings wherein an aluminum-lead alloy lining is bonded to a steel backing.

Abstract: The present invention provides high-strength, heat resistant aluminum alloys having a composition represented by the general formula:Al.sub.a M.sub.b X.sub.d or Al.sub.a M.sub.b Q.sub.c X.sub.e(wherein M is at least one metal element selected from the group consisting of Cu, Ni, Co and Fe; Q is at least one metal element selected from the group consisting Mn, Cr, Mo, W, V, Ti and Zr; X is at least one metal element selected from the group consisting of Nb, Ta, Hf and Y; and a, b, c, d and e are atomic percentages falling within the following ranges: 45.ltoreq.a.ltoreq.90, 5.ltoreq.b.ltoreq.40, 0<c.ltoreq.12, 0.5.ltoreq.d.ltoreq.15 and 0.5.ltoreq.e.ltoreq.10, the aluminum alloy containing at least 50% by volume of amorphous phase.

Abstract: A contact conductor for electric vehicles is produced from an aluminum alloy containing an excess of silicon. The alloy comprises 0.2-1% by weight magnesium, 1-7% by weight silicon and the balance being aluminum and incidental impurities. It has a tensile strength of at least 38,000 psi and a minimum electrical conductivity of 50% IACS.

Abstract: The present invention provides a composite aluminum plate suitable as a target for coating purposes, said plate comprising a surface layer melted on the basis of pure aluminum (Al.gtoreq.99.99), optionally consisting of a pure alloy, e.g., the members of which have a purity greater than or equal to 99.99%, melted on the basis of pure aluminum (Al.gtoreq.99.99); and (2) a supporting layer comprising a hardenable aluminum alloy having a Brinell hardness index HB of at least about 50 after being heat-treated under suitable conditions. This invention further provides a target suitable for physical or sputter coating processes, such as cathodic sputtering and magnetron sputtering. Methods for preparing such a plate and target are also provided.

Abstract: A process for enhancing the physical properties of superplastically formed and solution heat treated Aluminum-Lithium workpieces entails stretching near-net parts by from 2 to 10 percent at a specified temperature, followed by controlled aging.

Abstract: A process for the production of a series 7000 aluminum alloy (Al-Zn-Cu-Mg) with a high level of mechanical strength and good ductility, by spray deposition. The object is the production of aluminum alloys having an ultimate stress.gtoreq.800 MPa and an elongation.gtoreq.5%, as well as the production of alloys which are reinforced by ceramic particles. According to the process, a solid alloy is formed by spray deposition, the alloy is transformed in the hot condition at between 300.degree. and 450.degree. C. and possibly in the cold condition, and the transformed alloy is subjected to solution treatment, quenching and aging.

Abstract: A method is provided for producing a wrought aluminum eutectic composite characterized by improved physical properties. The method resides in forming a casting of an aluminum alloy characterized metallographically by the presence of a eutectic structure, and then heat treating the casting at a temperature related to the eutectic-forming temperature of said alloy casting, that is just below its incipient melting point. The heat treatment is continued for a time at least sufficient to convert the morphology of the eutectic to dispersed fine particles of reinforcing phase(s), following which the alloy is physically worked to reduce the cross section thereof and provide a wrought aluminum eutectic composite characterized by improved physical properties.

Abstract: Disclosed is a method of producing an unrecrystallized Al-Zn-Mg thin gauge flat rolled product, e.g., plate or sheet, having improved levels of strength and fracture toughness. The method comprises the steps of providing a body of a Zn-Mg containing aluminum base alloy, heating and hot working the body to a first product. This is followed by reheating, cooling and heat treating the first product prior to further working it to a thin gauge, unrecrystallized plate or sheet product, for example.

Abstract: An aluminum alloy composition represented by the following general formula (I):Al.sub.a Mg.sub.b Ni.sub.c Mn.sub.d Si.sub.e Cu.sub.f Fe.sub.g Ti.sub.h Zn.sub.i B.sub.k Zr.sub.l (I)whereinb=about 2-8 wt %c=0-about 7 wt %d=0-about 3.0 wt %e=0-about 1.0 wt %f=0-about 1.0 wt %g=0-about 0.5 wt %h=0-about 0.3 wt %i=0-about 0.3 wt %j=0-about 0.1 wt %k=0-about 0.1 wt % andl=0-about 0.3 wt %; provided thatc+d.gtoreq.about 0.5 wt %, anda is balance.

Abstract: A metal matrix composite may be produced by atomizing a stream of molten aluminum-lithium alloy to form a spray of hot metal particles by subjecting the stream to relatively cold gas directed at the stream, applying to the stream or spray fine solid particles of reinforcement e.g. silicon carbide, and depositing the metal having the fine particles incorporated therein. The resulting composite has the following properties in an extruded and age hardened state:0.2% Proof strength - at least 400 MPaTensile strength - at least 440 MPaElongation - at least 2.0%Modulus of elasticity - at least 85 GPaDensity - maximum 2.75 Mg/m.sup.3.

Abstract: The invention concerns an Al alloy product containing lithium, with great specific mechanical strength and high tolerance to damage, particularly resistance to corrosion under stress in processed state (quenched-tempered), particularly in recrystallized state, and a process to obtain said product.The products according to the invention present a specific microstructure, with numerous rather coarse precipitates of intermetallic phases which are rich in Al, Cu, Li, Mg and optionally also Zn, of which the volume fraction is between 0.6 and 4%. A differential enthalpic analysis allows verification that the product has been processed according to the method which is claimed.This method consists of applying the following thermal treatments to the alloy:an optional heat maintenance stage in the course of the manufacture (for wrought alloys) or before placement in solution (for the cast alloys) at a temperature of between 490.degree. and 250.degree. C. for 1 to 48 hours.a placement in solution between 460.degree. C.

Abstract: Disclosed is a method of producing an unrecrystallized A1-Zn-Mg thin gauge flat rolled product having improved levels of strength and fracture toughness. The method comprising the steps of providing a body of a Zn-Mg containing aluminum base alloy, working the body to a flat rolled product and then subjecting the product to a ramp anneal followed by solution heat treating, quenching and aging.

Abstract: Apparatus is provided for fabricating continuous metal strip composed of a low density, readily oxidizable aluminum based alloy. The allow is cast directly from the melt through a slotted nozzle onto a moving chill substrate. A scraping mechanism located upstream of the nozzle is adapted to ride on the substrate and remove therefrom the gaseous boundary layer associated therewith. Disposed between the scraping mechanism and the nozzle is a gas supply mechanism adapted to introduce a replacement gas that is carried by the substrate to the nozzle. A shielding means configured to form a semi-enclosed chamber around the nozzle and the substrate apparatus to direct and confine the replacement gas in the vicinity of the nozzle. The alloy preferably has the form of a foil and a composition consisting essentially of about 10 to 13 weight percent silicon, 0 to 3 weight percent magnesium, 0 to 4 weight percent copper, 0 to 0.

Abstract: Disclosed is a method of producing an unrecrystallized aluminum base, wrought product having improved levels of strength and fracture toughness. The method comprises providing a body of the aluminum base alloy, hot working the body to a wrought product and then subjecting it to an isothermal soak followed by a ramp anneal.

Abstract: Disclosed is a method of producing an unrecrystallized wrought aluminum-lithium product having improved levels of strength and fracture toughness. The method comprises the steps of providing a body of a lithium containing aluminum base alloy; heating the body to a hot working temperature and hot working the body to a first product. The product is cold worked to a second wrought product and then reheated while avoiding substantial recrystallization thereof, the reheating adapted to relieve stored energy capable of causing recrystallization during a subsequent heat treating step. The product is then solution heat treated, quenched and aged to provide a substantially unrecrystallized product having improved levels of strength and fracture toughness.

Abstract: A method is taught for the formation of intermetallic-second phase composite materials. The method involves the formation of a first metal-second phase composite comprising a relatively high loading of discrete, second phase particles distributed throughout a metal matrix, dilution of the first composite into an additional amount of metal to form a second composite comprising a lower loading of second phase particles within an intermediate metal matrix, and introduction of the second composite into another metal which is reactive with the intermediate metal matrix of the composite to form an intermetallic. A final intermetallic-second phase composite is thereby formed comprising a dispersion of discrete second phase particles throughout a final intermetallic matrix. The final intermetallic matrix may comprise a wide variety of intermetallic materials, with particular emphasis drawn to the aluminides and silicides. Exemplary intermetallics include Ti.sub.3 Al, TiAl, TiAl.sub.3, Ni.sub.3 Al, NiAl, Nb.sub.

Abstract: Disclosed is a method of producing an unrecrystallized, thin gauge cold rolled aluminum-lithium sheet product having improved levels of strength and fracture toughness. The method comprises the steps of providing a body of a lithium containing aluminum base alloy, heating the body to a hot rolling temperature, and hot rolling the body to a first intermediate sheet product. After cold rolling to a second intermediate thickness, the sheet product is reheated and hot rolled to produce a final sheet product while avoiding substantial recrystallization there, the hot rolling adapted to relieve stored energy capable of initiating recrystallization during a subsequent heat treating step. Thereafter, the sheet product is solution heat treated, quenched and aged to provide a substantially unrecrystallized product having improved levels of strength and fracture toughness.

Abstract: An aluminum base alloy having a composition selected from:(i)Cr 1.5% to 7.0% by weightZr 0.5% to 2.5% by weightMn 0.25% to 4.0% by weightAl remainder including normal impurities, and(ii) 7000 series Al alloys containing as added constituents:Cr 0.5% to 3.0% by weightZr 0.5% to 2.5% by weightMn 0.1% to 2.0% by weight.

Abstract: This invention relates to a metallic-second phase composites comprising a matrix of titanium aluminide with discrete titanium silicide particles dispersed therein. The second phase dispersoid is stabilized during the process of in-situ formation by the presence of zirconium.

Abstract: An aluminum alloy sheet according to the present invention essentially consists of an aluminum alloy containing 0.5 to 1.4% magnesium, 0.6 to 1.5% silicon, and 0.005 to 0.1% titanium, all by weight, and aluminum and inevitable impurities for the remainder, and is adjusted so that the ratio of the silicon content to the magnesium content is 0.65 or more. The average crystal grain size and the electric conductivity of the aluminum alloy sheet are 70 .mu.m or less and 43 to 51% IACS, respectively.The composition of the aluminum alloy is adjusted in this manner, and the crystal grain size and the electric conductivity are restricted within the specific ranges by controlling the manufacturing conditions. Thus, there may be provided an aluminum alloy sheet which is improved in arc-weldability and resistance to filiform corrosion, as well as in formability and bake-hardenability at low temperature.

Abstract: A matrix of an Al-Ni base alloy or an Al-Si-Cu base alloy is strengthened by dispersion of particles of Ni, Si or at least one intermetallic compound selected from among AlNi, Al.sub.3 Ni, Al.sub.3 Ni.sub.2 and AlNi.sub.3.

Abstract: The invention concerns a method for final heat treatment tempering at Al alloys containing Li and at least one other major element selected from the group Cu, Mg and Zn, as well as possible minor elements such as Zr, Mn, Cr, Ni, Hf, Ti and Be, in addition to inevitable impurities such as Fe and Si. The treatment involves a principal tempering operation which takes place at a time and temperature in an area defined by a parallelogram on a temperature log-time diagram, whose corners have the following coordinates: (A) 270.degree. C.--3 min; (B) 270.degree. C.--48 min; (C) 225.degree. C.--9 hrs 30 min; (D) 225.degree. C.--35 min. The heat treatment makes it possible to produce a satisfactory array of mechanical characteristics such as mechanical strength, ductility, or toughness and resistance to corrosion, which are higher than those achieved by means of conventional treatments of type T6 or by under-ageing operations.

Abstract: An aluminum base alloy wrought product having improved corrosion resistance in addition to combinations of strength and toughness. The product comprises 2.2 to 3.0 wt. % Li, 0.4 to 2.0 wt. % Mg, 0.2 to 1.6 wt. % Cu, 0 to 2.0 wt. % Mn, 0.5 wt. % max. Fe, 0.5 wt. % max. Si, the balance aluminum and incidental impurities and has the ability to develop improved combinations of strength and toughness in response to an aging treatment. Prior to an aging step, the product having imparted thereto a working effect equivalent to stretching so that after an aging step it has improved combinations of strength and toughness.

Abstract: An Al-Si-Mg series aluminum-alloy rolled sheet for forming, having improved formability, corrosion-resistance, and weldability, essentially consisting of Si and Mg, whose contents are on and within the line connecting points A, B, C, D, E, and F of FIG. 1, except for the line FA, from 0.05 to 0.5% of Fe, and balance aluminum and unavoidable impurities, with the proviso that:______________________________________ Si (%) Mg (%) ______________________________________ A: 1.8 0.1 B: 2.5 0.1 C: 2.5 1.1 D: 1.2 1.1 E: 1.2 0.6 F: 1.8 0.

Abstract: The invention relates to aluminum alloy products containing 1 to 3.5% Li, up to 4% Cu, up to 5% Mg and up to 3% Zr, and additions of Mn, Cr and/or Zr, in which:Zn.ltoreq.0.10%, Mn.ltoreq.0.8%, and Cr.ltoreq.0.20%, ##EQU1## The alloy is recrystallized and has an average grain size of less than 200 .mu.m.

Abstract: A stable age hardenable aluminum alloy which has useful mechanical properties at temperatures up to at least 900.degree. F. (482.degree. C.). The alloy contains 5-15% iron, 1-5% molybdenum and 0.2-6% vanadium with balance aluminum and is processed by rapid solidification from the melt to form a particulate which is consolidated to form a bulk article.

Abstract: A rapidly solidified aluminum-base alloy consists essentially of the formula Al.sub.bal Fe.sub.a Si.sub.b V.sub.c, wherein "a" ranges from 3.0 to 7.1 atom percent, "b" ranges from 1.0 to 3.0 atom percent, "c" ranges from 0.25 to 1.25 atom percent and the balance is aluminum plus incidental impurities, with the provisos that (i) the ratio (Fe+V): Si ranges from about 2.33:1 to 3:33:1 and (ii) the ratio Fe:V ranges from 11.5:1 to 5:1. The alloy exhibits high strength, ductility and fracture toughness and is especially suited for use in high temperature structural applications such as gas turbine engines, missiles, airframes and landing wheels.

Abstract: An easy method and apparatus to eliminate casting defects from composite materials of hypereutectic Al-Si alloys and improve their properties. The product composite materials with primary silicon crystals of several microns have fine homogeneous microstructures and mechanical properties comparable to similar materials produced by the conventional powder metallurgy technology. Highly wear-resistant composite materials, in which the hypereutectic Al-Si alloy and strengthening material are homogeneously mixed, can be obtained with ease. The hypereutectic Al-Si alloy and strengthening material are homogeneously mixed by stirring blades rotated at low speed. The obtained molten composite alloy rotated at high speed about a horizontal shaft in a heat-resistant vessel. The rotor rotating and stirring at high speed spatters the molten composite alloy material to break up the crystallizing out primary silicon crystals.

Abstract: A method for thermally treating an article made from an aluminum alloy having a first temperature at which solute atoms cluster to yield nuclei for the formation and growth of strengthening precipitates, and a second higher temperature at which the strengthening precipitates dissolve. The method comprises: heating the article to allow substantially all soluble alloy components to enter into solution; rapidly cooling the article in a quenching medium; and precipitation hardening the article by aging at or below the first temperature for a few hours to several months; then aging above the first temperature and below the second temperature until desired strength is achieved. A method for imparting improved combinations of strength and fracture toughness to a solution heat treated-article which includes an aluminum-lithium alloy is also disclosed. This method comprises aging the article at one or more temperatures at or below a first temperature of about 93.degree. C. (200.degree. F.

Abstract: A contact conductor for electric vehicles is produced from an aluminum alloy containing an excess of silicon. The alloy comprises 0.1-1% by weight magnesium, 1-7% by weight silicon and the balance being aluminum and incidental impurities. The conductor is produced by the steps of: (1) casting the alloy into a continuous bar, (2) hot rolling to rod without intermediate cooling, (3) quenching the hot rolled rod, (4) cold deforming the quenched rod and (5) subjecting the cold deformed rod to artificial aging.

Abstract: Disclosed is a method of making lithium containing aluminum base alloy products having improved properties in the short transverse direction. The method comprises the steps of providing a body of a lithium containing aluminum base alloy and heating the body to a temperature for initial hot working but at a temperature sufficiently low that a substantial amount of grain boundary precipitate is not dissolved. The method further includes hot working the heated body to provide an intermediate product, recrystallizing the intermediate product and then hot working the recrystallized product to a final shaped product. The final shaped product is solution heat treated, quenched and aged to provide a non-recrystallized final product having improved levels of short transverse properties.

Abstract: The combination of strength and fracture toughness properties of aluminum-lithium alloys are significantly enhanced by underaging the alloys at temperatures ranging from 200.degree. F. to below 300.degree. F. for relatively long periods of time.

Abstract: A method of producing a recrystallized aluminum-lithium product having improved levels of strength and fracture toughness is disclosed. The method comprises the steps of: providing a lithium-containing aluminum base alloy comprised of 0.5 to 4.0 wt. % Li, 0 to 5.0 wt. % Cu, 0 to 5.0 wt. % Mg, 0.10 to 1.0 wt. % of a grain structure control element selected from the class consisting of Zr, Cr, Hf, Ti, V, Sc, and Mn, 0.5 wt. % max. Fe, and 5 wt. % max. Si, with the balance consisting essentially of aluminum and incidental elements and impurities; heating the body to a high presoak temperature to homogenize the alloy; cooling the alloy to a first hot working temperature; reheating the alloy, after hot working, back to a high annealing temperature; cooling the alloy to a second hot working temperature to produce a first product; reheating the alloy to a lower annealing temperature; and then cold working the alloy.

Abstract: The invention concerns a method for final heat treatment ageing of Al alloys optionally containing Li and at least one other major element selected from the group Cu, Mg and Zn, as well as possible minor elements such as Zr, Mn, Cr, Ni, Hf, Ti and Be, in addition to inevitable impurities such as Fe and Si. The treatment involves a principal ageing operation which takes place at a time and temperature in an area defined by a parallelogram on a temperature log-time diagram, whose corners have the following coordinates: A 270.degree. C.-3 min; B 270.degree. C.-48 min; C 225.degree. C.-9 hrs 30 min; D 225.degree. C.-35 min. The heat treatment makes it possible to produce a satisfactory array of mechanical characteristics such as mechanical strength, ductility, or toughness and resistance to corrosion, which are higher than those achieved by means of conventional treatments of type T6 or by under-ageing operations.

Abstract: An aluminum-alloy rolled sheet particularly suitable for use for an automotive body contains from 0.4 to 2.5% of Si, and Mg and Cu in an amount depending upon the Si content as follows:(a) in the case of 0.4.ltoreq.Si.ltoreq.1.0%, 0.1.ltoreq.Mg<0.4%, and 0.3<Cu.ltoreq.1.5%;(b) in the case of 1.0<Si.ltoreq.1.8%, 0.1.ltoreq.Mg<0.25% and 0.3%<Cu.ltoreq.1.5%; and,(c) in the case of 1.8<Si.ltoreq.2.5%, 0.1.ltoreq.Mg<0.25% and Cu.ltoreq.1.5%,and further contains from 0.05 to 0.4% Fe, the balance being aluminum and unavoidable impurities.The sheet has an improved formability and a yield strength of 15 kg/mm.sup.2 or more can be obtained after paint baking.

Abstract: An aluminum base alloy wrought product having an isotropic texture and a process for preparing the same is disclosed. The product has the ability to develop improved properties in the 45.degree. direction in response to an aging treatment and is comprised of 0.5 to 4.0 wt.% Li, 0 to 5.0 wt.% Mg, up to 5.0 wt.% Cu, 0 to 1.0 wt.% Zr, 0 to 2.0 wt.% Mn, 0 to 7.0 wt.% Zn, 0.5 wt.% max. Fe, 0.5 wt.% max. Si, the balance aluminum and incidental impurities. The product has imparted thereto, prior to a hot rolling step, a recrystallization effect to provide therein after hot rolling a metallurgical structure generally lacking intense work texture characteristics. After an aging step, the product has improved levels of properties in the 45.degree. direction.

Abstract: A process for improving the properties of low density aluminum alloys comprises a controlled heat and cooling treatment of a shaped alloy to obtain a product which in the non-aged condition has improved fracture toughness without sacrificing tensile properties. The product is particularly useful for treating forged Al-Li-Mg alloys.

Abstract: An aluminum alloy is provided which has a surface with a fine grain structure. It is produced by overaging an aluminum alloy and then cold working only the surface by shot peening or other surface working technique. The alloy is then heated so that the overaged, cold-worked surface recrystallizes into a fine grain structure.

Abstract: An aluminum base alloy wrought product having improved corrosion resistance in addition to combinations of strength and toughness. The product comprises 2.2 to 3.0 wt. % Li, 0.4 to 2.0 wt. % Mg, 0.2 to 1.6 wt. % Cu, 0 to 2.0 wt. % Mn, 0.5 wt. % max. Fe, 0.5 wt. % max. Si, the balance aluminum and incidental impurities and has the ability to develop improved combinations of strength and toughness in response to an aging treatment. Prior to an aging step, the product having imparted thereto a working effect equivalent to stretching so that after an aging step it has improved combinations of strength and toughness.