An improved apparatus and method of fabricating long nanostructured or ultrafine grained tubes includes, in one implementation, expanding and extruding a sample material through cyclic deformations. The first cycle begins with expanding the sample through a die unit by applying pressure using a punch box, then with extruding the sample by applying back pressure using a stationary mandrel, which in turn reduces the expanded sample diameter to the original diameter. The next cycle begins with inverting the die unit to further extrude the sample with no need to apply back pressure. Furthermore, resistant forces against the sample are reduced by using a lubricant material inside the die unit, thus allowing continuation of additional cycles without constraining the sample length, resulting in desired strength and elongation.

Disclosed herein is a method of forming a high strength aluminum alloy. The method comprises heating an aluminum material to a solutionizing temperature for a solutionizing time such that the magnesium and zinc are dispersed throughout the extruded aluminum material to form a solutionized aluminum material. The method includes quenching the solutionized aluminum material to form a quenched aluminum material. The method also includes aging the quenched aluminum material to form an aluminum alloy, then subjecting the aluminum alloy to an ECAE process to form a high strength aluminum alloy.

Shear-assisted extrusion processes for forming extrusions of a desired composition from a feedstock material are provided. The processes can include applying a rotational shearing force and an axial extrusion to the same location on the feedstock material. Devices for this can include a die tool defined by a die face extending from a rim of the die face inwardly at an angle greater than zero in relation to a sidewall of the die tool in at least one cross section; and/or a die tool defining an opening configured to receive feedstock material for extrusion and further defining a die face defining a recess within the die face and contiguous with the opening. Shear-assisted extrusion processes are also provided that can mix different portions of the feedstock material within a recess about the opening prior to feedstock material entering the opening; and extruding the mixed portions.

A process to fabricate ultra-fine grain metal hollow object, comprising: inserting an annealed hollow prototype in an Equal Channel Angular Pressing (ECAP) die, providing a flexible elastic polyurethane mandrel to fill the central hollow space, optionally (if needed) provide polyurethane support to fill the spaces between the outer boundary of the prototype and the inner surface of the ECAP channel and to exert sufficient pressure to complete the ECAP process. The process is designed to improve thermal conductance and mechanical properties of hollow metal parts and is especially applicable to achieving the maximal heat conductance and tensile strength of titanium piping, construction tubing, and cylindrical reactors.

Systems, methods, and apparatuses are provided herein to thermomechanically process a workpiece to increase the strength in terms of hardness and the electrical conductivity of the workpiece. In some embodiments, a shear strain is induced in a workpiece at a temperature or within a range of temperatures, and the workpiece is rotated about its longitudinal axis. Then, another shear strain is induced in the workpiece. In various embodiments, four shear strains are induced in a workpiece, and the workpiece is rotated between shear strains. The shear strains, temperatures, and rotations contribute to the increase in density of dislocations, precipitation growth, and refinement of grain size. The result is a workpiece such as AA1xxx aluminum with an increase in hardness and electrical conductivity.

A process to fabricate ultra-fine grain metal hollow object, comprising: inserting an annealed hollow prototype in an Equal Channel Angular Pressing (ECAP) die, providing a flexible elastic polyurethane mandrel to fill the central hollow space, optionally (if needed) provide polyurethane support to fill the spaces between the outer boundary of the prototype and the inner surface of the ECAP channel and to exert sufficient pressure to complete the ECAP process. The process is designed to improve thermal conductance and mechanical properties of hollow metal parts and is especially applicable to achieving the maximal heat conductance and tensile strength of titanium piping, construction tubing, and cylindrical reactors.

A method of forming a high strength aluminum alloy. The method comprises heating an aluminum material including scandium to a solutionizing temperature of the aluminum material such that scandium is dispersed throughout the aluminum material to form an aluminum alloy. The method further comprises extruding the aluminum alloy with equal channel angular extrusion to form a high strength aluminum alloy, such that the high strength aluminum alloy has a yield strength greater than about 40 ksi after being at a temperature from about 300 C. to about 400 C. for at least one hour.

An aluminum alloy is provided that is used to produce a high-strength aluminum alloy extruded material that exhibits excellent formability. The aluminum alloy consists of 0.30 to 1.00 mass % of Mg, 0.6 to 1.40 mass % of Si, 0.10 to 0.40 mass % of Fe, 0.10 to 0.40 mass % of Cu, 0.005 to 0.1 mass % of Ti, 0.3 mass % or less of Mn, 0.01 to 2.0 mass % of Zn, and 0.10 mass % or less of Zr, with the balance being aluminum and unavoidable impurities, the aluminum alloy having a stoichiometric Mg.sub.2Si content of 0.60 to 1.30 mass % and an excess Si content of 0.30 to 1.00 mass %.

Various embodiments provide for an extrusion device with a dummy block having a curved surface configured to change the shape and length of charge welds between extrudates originating from different billets in order to reduce the amount of scrap and waste material. In an embodiment, the dummy block, which forces the billet of material through the die, can have a concave front surface such that the material, as it is extruded through the die, forms a solid-state weld that is shorter than a flat faced dummy block. In another embodiment, the dummy block can have a convex front surface such that the material, as it is extruded through the die, forms a solid-state weld that is longer than a weld due to a flat faced dummy block. In other embodiments, billets with non-flat ends can also be used.

A method for manufacturing a super-refractory nickel-based alloy with a constituent composition such that the gamma-prime average precipitation quantity at 700 C. is at least 35 mol % includes a preparation step in which a material with a crystal grain diameter of 200 m or less is manufactured by hot extrusion and a processing step in which this material is subjected to cold plastic processing with a processing rate of at least 30%. The cold plastic processing can be performed a plurality of times with a cumulative processing rate of at least 30%, and heat treatment is not performed between instances of cold plastic processing. The super-refractory nickel-based alloy can have a linear organization of a gamma phase and a gamma-prime phase or can include a carbide aggregated in an isometric crystal organization that includes a gamma phase and a gamma-prime phase.