Abstract: A method for producing microporous objects with fiber, wire or foil core with periodic welding of nodes by movement of the substrate and the making of a porous mat. Microporous objects are created by deposition of small dimension of solid from liquid streams undergoing solidification with the simultaneous welding of the streams at various nodal locations concurrently during the deposition process. Bulk porous material objects are created containing open spaces within the microstructure. Inserts can be added to create internal geometries. Variations in pore density from near-zero to about 95% with gradient densities can be created. Screens can be used for forming column-like supports within the microporous object. Holes can be punched in the fiber core to create desired properties of denser regions and to limit the thermal expansion of the mat in a single direction.

Abstract: In metal stamping dies, by taking advantage of improved material flow by selectively warming the die, flat sections of the die can contribute to the flow of material throughout the workpiece. Local surface heating can be accomplished by placing a heating block in the die. Distribution of heating at the flat lower train central regions outside of the bend region allows a softer flow at a lower stress to enable material flow into the thinner, higher strain areas at the bend/s. The heating block is inserted into the die and is powered by a power supply.

Abstract: An apparatus and method for producing a rapidly solidified ingot characterized by a fine scale microstructure capable of precipitating uniformly dispersed fine particles. A charge of the material is placed in a crucible and heated by a furnace to melt the charge. The melt is discharged from the crucible in a stream along a pouring axis. An ingot mold is oriented at an angle with respect to the pouring axis so that the stream is received in the mold. As the melt is being poured into the mold, the mold is rotated about its central axis at a predetermined speed to continuously shear, both circumferentially and downwardly, a thin layer of the melt from the stream as the stream contacts the sidewall surfaces of the mold. The thin layer is rapidly solidified by the extraction of heat through the mold and is formed, as said ingot mold fills and successive layers are solidified, into an ingot having a fine microstructure capable of developing uniformly dispersed fine particles.

Abstract: A process is disclosed for fabricating a metal aluminide composite which comprises providing a metal aluminide, such as titanium aluminide, or a titanium aluminide alloy, and a reinforcing fiber material, such as silicon carbide fiber, and placing an interlayer or diffusion barrier layer in the form of a metal selected from the group consisting of silver, copper and gold, and alloys thereof, between the metal aluminide and the reinforcing fiber material. The interlayer metal can be a foil of the metal or in the form of a coating, such as a silver coating, on the reinforcing fiber material. The metal aluminide, the reinforcing fiber material, and the metal interlayer, e.g., in the form of a packet of a plurality of alternate layers of metal aluminide alloy and reinforcing fiber material, each layer being separated by the metal interlayer, is pressed and heated at an elevated temperature, e.g., ranging from about 900.degree. to about 1200.degree. C., at which diffusion bonding occurs.

Abstract: A solid state joint and a method of making a solid state joint between aluminum or magnesium alloys is provided. The joint consists of a diffusion bond with unmelted pieces of a fragmented foil dispersed along the diffusion bond. The joint is made by placing a friable foil between the parts being joined and pressing the parts together to crack the foil. The assembly is then heated and pressed together for a sufficient time, temperature, and pressure to cause the aluminum or magnesium alloy to flow into the cracks, across the foil, and then to diffusion bond together. The foil is made from a material which is harder than the alloy being joined and which will not melt at the bonding temperature.

Abstract: A monitor is provided for measuring and controlling the strain rate of a blank during forming. A light source directs light against the blank and a video camera is positioned and focused to view the light reflected from the blank while it is being formed. A video monitor and an image processor receive the signal from the camera. This signal is used to determine the strain rate based upon the dimensional change in reference marks on the blank. The image processor provides an output signal which can be used to control the strain rate in accordance with a predetermined strain rate profile for the particular part being formed.

Abstract: A softer metal such as aluminum, or a metal forming a metal aluminide, or an alloy containing these metals is added to a metal aluminide composite during fabrication to promote easy consolidation of the metal aluminide matrix with the reinforcing phase. The metal aluminide may be titanium aluminide, nickel aluminide, or iron aluminide. The softer metal, the metal aluminide matrix, and the reinforcing phase are pressed together at a temperature above the softening temperature of the softer metal. The softened metal promotes flow and consolidation of the matrix and the reinforcement at relatively low temperatures. The composite is held at an elevated temperature to diffuse and convert the soft metal phase into the metal aluminide matrix. By consolidating at a lower temperature, cracking tendencies due to thermal expansion differences between the matrix and reinforcement is reduced. By consolidating at a lower pressure, mechanical damage to the fibers is avoided.

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: A rapidly-solidified aluminum alloy powder having a nominal composition of 7% Zn, 2.5% Mg, 2% Cu, 0.3% Zr, and 0.3% Cr is used to make a high forming-rate, superplastic, high-strength aluminum alloy. The powder is outgassed, consolidated, and extruded, thereby developing a wide range of particle size distribution of dispersoids in the process, containing respectively zirconium and chromium dispersoids, as well as age hardening precipitates. The consolidated powder is then rolled to 85% reduction to provide a sheet material which is superplastically formed at a temperature in the range of 450.degree. C. to 490.degree. C. and at a rate between 5.times.10.sup.-3 to 5.times.10.sup.-2 per second.

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: A composite is produced by placing a reinforcement between foils of a superplastic metal alloy to provide stack. The stack is then heated to a temperature at which the metal alloy exhibits its superplastic properties, and pressure is applied to the heated stack. This causes the foils to flow around the reinforcement and diffusion bond together in the solid state. A structural composite is thus formed comprising a reinforcement dispersed throughout a matrix of superplastic metal alloy.

Abstract: A sheet of material is held in a die opposite a forming surface of the die, and gas pressure is applied to both sides of the sheet. The pressure creates a compressive stress in the sheet thickness direction sufficient to cause plastic flow. By maintaining the pressure higher on the side of the sheet opposite to the forming surface, the sheet bends and expands toward the die forming surface. This pressure differential can be increased as necessary to bend the sheet into the crevices which make up the details of the forming surface. The sheet may be heated during forming to lower the compressive stress which is required to cause it to flow plastically.