Abstract: Superplastically formable aluminum alloys and composite materials are prepared from rapidly solidified, coarse aluminum powder of a precipitation hardenable alloy, processed to have a low oxide and contaminant content. The powder is mixed, together with reinforcement in the case of the composite material, and then consolidated and extruded at a high extrusion ratio to promote microstructural uniformity and to break up the surface oxide present on the particles. The extrusion is then thermomechanically processed to impart a recrystallized fine-grain aluminum microstructure which is suitable for use in superplastic forming. The unreinforced powder alloy exhibits uniform elongations of over 800 percent at a strain rate of 2.times.10.sup.-4 per second, and a composite having 0.10 volume fraction silicon carbide reinforcement exhibits uniform elongations of over 450 percent at the same strain rate.

Abstract: A method is provided for imparting a very fine grain size to aluminum alloys, including alloys in the form of sheet or heavy sections such as forging billets. The alloy is first aged to form precipitates. The aged alloy is then deformed along its three principal axes in successive operations until a cummulative true strain of at least 8 is achieved.

Abstract: Superplastic forming of aluminum work stock is improved by including therein about 0.05% to about 10% or 15% scandium. In preferred practices, soluble elements such as magnesium are also included in the aluminum alloy.

Abstract: The present invention provides a low density aluminum-base alloy, consisting essentially of the formula Al.sub.bal Zr.sub.a Li.sub.b Mg.sub.c T.sub.d, wherein T is at least one element selected from the group consisting of Cu, Si, Sc, Ti, V, Hf, Be, Cr, Mn, Fe, Co and Ni, "a" ranges from about 0.25-2 wt %, "b" ranges from 2.7-5 wt %, "c" ranges from about 0.5-8 wt %, "d" ranges from about 0.5-5% and the balance is aluminum. The alloy has a primary, cellular-dendritic, fine-grained, supersaturated aluminum alloy solid solution phase with intermetallic phases of the constituent elements uniformly dispersed therein. A consolidated article can be produced by compacting together particles composed of the aluminum alloy of the invention in a vacuum at elevated temperature. The compacted alloy is solutionized by heat treatment, quenched in a fluid bath, and optionally, stretched and aged.

Abstract: This invention relates to a superplastic aluminum alloy comprising Mg, Cu, and at least one of Mn, Cr and Zr. The alloy has an elongation substantially of from 330% to 800% and can be readily produced.

Abstract: A method for the manufacture of a highly ductile material comprises melting an alloy material in a crucible held under a vacuum, inserting a stirring bar in the molten alloy material in the crucible and rotating the stirring bar at a low speed, causing the stirring bar to be rotated at a high speed after the molten alloy material has reached the temperature for starting solidification, and continuing the high speed rotation of the stirring bar until immediately before completion of the solidification.

Abstract: A method of forming a stiffened panel from first and second metal sheets, at least the first sheet being capable of both superplastic deformation and diffusion bonding, and also provided with at least one control region of different thickness compared with other regions of the sheet, includes the steps of:attaching the sheets together at a series of attachment lines across their faces, the attachment lines and the control region or regions being in predetermined relationship with one another, placing the attached sheets in a mould and heating to within that temperature range within which superplastic deformation and diffusion bonding takes place,urging those areas of the first sheet between the attachment lines away from the second sheet by a common differential pressure at a rate within that range of strain rates at which superplastic deformation occurs to form a series of cavities between the two sheets such that peripheral parts of those areas urged away from the second sheet form side walls of neighboring

Abstract: Superplastic aluminum alloy strips comprising 1.5 to 90% of magnesium, 0.5 to 5.0% of silicon, 0.05 to 1.2% of manganese, 0.05 to 0.3% of chromium and the balance consisting essentially of aluminum, and also a process for producing superplastic aluminum alloy strips comprising continuously casting and rolling a molten aluminum alloy containing 1.5 to 9.0% of magnesium, 0.5 to 5.0% of silicon, 0.05 to 1.2% of manganese and 0.05 to 0.3% of chromium, thereby obtaining a cast strip of 3 to 20 mm in thickness, homogenizing the cast strip at a temperature of 430.degree. to 550.degree. C., and subjecting the homogenized strip to cold rolling until the reduction ratio reaches up to a value of not less than 60%.

Abstract: Sheets of high strength superplastic Al--Zn--Mg alloys or Al--Cu alloys which having a maximum grain size below 30 .mu.m on average are described. These alloy sheets are obtained by a method which is characterized by keeping a homogenized and hot worked ingot of the alloy at two different temperatures for sufficient times whereby a fine grain structure is formed in the alloy to impart superplasticity to the alloy.

Abstract: There are provided superplastic alloys formed by electrodeposition of the alloy onto a cathode from an electrolyte containing a first metal ion, which is iron, nickel or cobalt, and a second constituent different from the first, which is iron, nickel, cobalt, tungsten or molybdenum, or a colloidal dispersoid. The products formed are fine-grain deposits free of intergranular embrittling films, and exhibit grain boundary flow at a superplastic temperature below a recrystallization temperature of the deposit. Nickel-cobalt alloys are preferred, and are deposited from halide-free sulfamate baths, with care being taken to eliminate all anode oxides from the system. In a complex structure, the approximate initial hardware contour is formed by electrodeposition, and the final structure formed by superplastic forming.

Abstract: A method of superplastically deforming a blank of a metallic alloy which:1. has a composition suitable for superplastic deformation and2. has a grain structure suitable for superplastic deformation and3. contains less than that percentage of a constituent known to inhibit grain coarsening after recrystallization which is necessary for such inhibition,comprising raising the blank to a forming temperature, deforming the blank at a first strain rate to induce dynamic recrystallization and continuing to deform the blank at a second strain rate lower than the first rate.

Abstract: A method of superplastically forming an article from a light metal base alloy, of the kind capable of having its crystal structure modified by cold working in such a way that subsequent dynamic recrystallization by hot working is facilitated, comprises cold working a first blank of the alloy to form a second blank having the modified crystal structure, and then forming the second blank into the article by hot working so that dynamic recrystallization is induced and super plastic deformation occurs. The degree of modification of the crystal structure during cold working is such that as the dynamic recrystallization continues, the grain size is progressively refined.

Abstract: Process for producing superplastic aluminum alloy strips comprising continuously casting and rolling a molten aluminum alloy containing 4.0 to 6.0% (by weight) of magnesium, 0.4 to 1.5% (by weight) of manganese, 0.05 to 0.2% (by weight) of chromium and less than 0.50% (by weight) of silicon, thereby preparing a cast strip of 3 to 20 mm in thickness, after subjecting the cast strip to annealing treatment at a temperature of 420.degree. to 530.degree. C., subjecting the annealed strip to the former step of cold rolling and intermediate annealing and then subjecting the intermediately annealed strip to the latter step of cold rolling until the reduction ratio reaches to a value of not less than 60%.

Abstract: A component, such as a turbine disk, made from a metal or metal alloy which has been processed to display superplastic properties at elevated temperatures, is diffusion bonded to a component or components, such as turbine blades, made from another metal or metal alloy, by disposing the components in a press with the surfaces to be bonded in mating contact. Moisture and oxygen are removed from between the surfaces. Heat and pressure are then applied, such as by forging at an elevated temperature or by hot isostatic pressing, to cause superplastic deformation of at least one of the components at the bonding surfaces. The heat and pressure are held sufficiently long to diffusion bond the surfaces. The new integral assembly is then heat treated to obtain desired properties. Consistently good diffusion bonds are achieved by this method.

Abstract: A method for producing superplastic aluminum alloys, including a hot/warm rolling operation is disclosed. Use of this method eliminates the need for overaging the material prior to rolling.

Abstract: A method of forming superplastic aluminum is disclosed. The prior need for overaging prior to rolling is eliminated by rolling the aluminum beginning at a hot rolling temperature and ending at a warm rolling temperature.

Abstract: The use of a sequentially applied warm working/cold working procedure in the conventional steps of preparing heat treatable superplastic alloys yields material which demonstrates substantially equiaxed fine grain structure and improved superplastic forming characteristics.

Abstract: A method of increasing the ductility of articles formed from a superplastic alloy, the superplastic alloy consisting of aluminium, from 5 to 10% by weight of calcium and at most 1% by weight of impurities, characterized in that these articles, after their superplastic forming, are heated for at least 30 minutes to a temperature of between 400.degree. C. and 600.degree. C.