Abstract:
An apparatus and methods for clamping around a manufacturing tool engaging a work piece are described. In one embodiment, a clamp includes a moveable support arranged to at least partially surround a circumference defining a work area. A friction reducing element is attached to the support to apply pressure to the surface when the clamp is engaged with the work piece, and to allow the clamp to be moved with the manufacturing tool. In accordance with other aspects of the invention, the clamp co-annularly or partially surrounds the manufacturing tool. In another embodiment, the manufacturing tool is a friction stir welding tool.
Abstract:
A method of mitigating distortion in a friction stir weld joint as well as an associated friction stir weld assembly for mitigating distortion in a friction stir weld joint are provided. In this regard, a workpiece having a friction stir weld joint and associated distortion may be provided. Force may then be selectively applied to the workpiece along at least a portion of friction stir weld joint. The application of force induces plastic deformation along at least the portion of the friction stir weld joint in order to reduce the distortion of the workpiece. Force may be applied, for example, by moving a roller, such as a hardened cylindrical roller having chamfered edges, along at least a portion of the friction stir weld joint in order to apply a compressive force.
Abstract:
A method of inhibiting grain growth and restricting grain size during heat-treatment and hot-working of metallic materials. A small volume of inert gas is added to a metallic material so that the inert gas is dispersed throughout the metallic material. The metallic material is then heated sufficiently high so that the inert gas forms micropores within the metallic material; the micropores interact with grain boundaries to inhibit grain growth. If desired, all or part of the residual microporosity may be eliminated from the metallic material during the final step of a deformation processing cycle.
Abstract:
A method for forming an aluminum alloy article having improved mechanical properties using a solid-state joining process in which the problem of ductility reduction is minimized by conducting a thermal exposure treatment prior to solution heat treatment. This thermal exposure treatment, done at a temperature below the solution heat treatment temperature, releases stored energy in the aluminum-alloy material. The aluminum-alloy material then does not have sufficient energy to cause recrystallization and abnormal grain growth during the subsequent solution heat treatment process. The resultant aluminum-alloy material has a restored mechanical strength with only a minor, but acceptable, decrease in original ductility.
Abstract:
A sealant for a weld joint and an associated weld joint and method are provided. The sealant includes aluminum and germanium and is characterized by a melting temperature that is lower than the melting temperature of the structural member that is joined. The sealant, which is disposed between faying surfaces of the structural members, can fill the spaces between the structural members to prevent the entry of chemicals, moisture, debris, and other substances, thereby reducing the likelihood of corrosion of the joint or structural members at the interface. Further, the sealant can be diffusion bonded to the faying surfaces, for example, by the heat generated during the joining process.
Abstract:
A method and apparatus for processing a sheet of material. The sheet of material may be secured relative to a tool in an incremental sheet metal forming machine. The sheet of material may be incrementally shaped into a shape of a part using a stylus. The stylus may comprise a rod having a first end and a second end, a substantially curved surface on the first end, and a texture on at least a portion of the substantially curved surface on the first end. The texture may be configured to channel a lubricant onto the first end.
Abstract:
A method of manufacturing a workpiece is provided. The method generally includes friction stir welding at least one structural member, selectively removing material from the surfaces of the workpiece at the location of a friction stir weld joint, and thereafter subjecting the workpiece to a solution treat, quench, and age treatment. By selectively removing regions from the surfaces of the workpiece that are defined by nonuniform material properties adapted to nucleate nonuniform grain growth during the solution treat, quench, and age treatment, a subsequent grain growth during the thermal treatment can be at least partially prevented.
Abstract:
The face sheet is formed of a titanium alloy which includes boron that can be superplastically formed and diffusion bonded to form a structural panel. The structural panel generally includes a pair of face sheets that are disposed on and bonded to opposite sides of a metallic core. By forming at least one of the face sheets of a titanium alloy which includes boron, such as between about 0.2 weight percent and about 2 weight percent of boron, the resulting structural panel is stiffened without any corresponding increase in weight relative to structural panels formed of conventional titanium alloys. Preferably, powdered titanium diboride (TiB.sub.2) is added to a titanium alloy charge that is subsequently formed into a boron reinforced titanium alloy sheet. During the forming process, the TiB.sub.2 reacts to produce TiB reinforcements that are scattered throughout the metal matrix to increase the modulus and correspondingly stiffen the resulting face sheet.
Abstract:
Three aluminum-lithium alloys are provided for high performance aircraft structures and engines. All three alloys contain 3 wt % copper, 2 wt % lithium, 1 wt % magnesium, and 0.2 wt % zirconium. Alloy 1 has no further alloying elements. Alloy 2 has the addition of 1 wt % iron and 1 wt % nickel. Alloy 3 has the addition of 1.6 wt % chromium to the shared alloy composition of the three alloys. The balance of the three alloys, except for incidentql impurities, is aluminum. These alloys have low densities and improved strengths at temperatures up to 260.degree. C. for long periods of time.
Abstract:
A method of superplastically forming aluminum alloy composites employs explosive bonding to produce strong, consistent bonds and annealing treatment to produce a fine microstructure in the bonded alloy sheets. The bonded alloy sheets having the fine microstructure can then be formed by superplastic methods to produce complex parts and structural elements.