Abstract: Metal sheets and thin-wall metal tubes may be heated to a hot working temperature and transformed by a hot-blow-forming step to achieve shapes, difficult to attain, without excessive thinning or strain causing damage to the workpiece based on the inherent formability of the metal alloy. The stages of forming of the intended shape in the metal workpiece are analyzed and workpiece regions of potential damage during forming are identified. Then, during actual forming, these regions of the hot workpiece are selectively cooled with air (or other cooling fluid) to reduce thinning or strain in the critical region(s) and to redistribute this strain to adjacent lower strain areas of the workpiece. This hot-blow-forming practice is particularly useful in attaining complex shapes in workpieces of aluminum-based alloys and magnesium-based alloys.

Abstract: Double-action clinching includes establishing a first layer on a second layer, and securing the layers between a tool's punch and clinching punch. First layer has less ductility than second layer, and clinching punch diameter is smaller than punch diameter. Layers are secured so: a tool support receives a portion of a second layer surface; clinching punch, slidably positioned in the support, is adjacent another portion of the second layer surface; and punch, positioned opposed to clinching punch, is adjacent a portion of a first layer surface. Pressing the punch into the first layer surface portion forms an aperture through the first layer. Pressing the clinching punch, in a direction opposite to the punch pressing, into the other portion of the second layer surface forces portion(s) of the second layer into the aperture, and forms a micro-interlocking flush-back joint between an aperture side wall and the second layer portion(s).

Abstract: A method for stamping a desired shape from a sheet blank includes providing the sheet blank. The method also includes locally cooling the sheet blank with a stream of fluid in a predetermined area of high stress concentration to be experienced during forming of the sheet blank into a desired shape. The method additionally includes forming the metal sheet blank into the desired shape in a stamping press with a punch. A system employing the method for forming a sheet blank is also disclosed.

Abstract: In substantial volume production operations involving hot blow forming or hot stamping of aluminum alloy sheet workpieces, debris largely comprised of particles of aluminum alloy material adheres to critical forming surfaces of the heated steel tools. This debris mars forming surfaces and causes defects in aluminum alloy parts formed against them. Such aluminum-rich debris may be reactively transformed to change its adherent properties and removed from tool surfaces without removing the heated tool from production. In one embodiment, a hot sacrificial magnesium sheet may be formed on the tool(s) to alloy with aluminum debris and carry it from the forming surface.

Abstract: A method for forming an aperture includes stamping an aperture into the article using a pellet, and refining aperture shape(s) and/or aperture dimensions. Methods for forming articles having reduced residual compressive stress are also disclosed. Very generally, the methods include establishing a diamond coating on at least a portion of a substrate, and applying a stress-relief process to the diamond coating, the substrate, or combinations thereof.

Abstract: Some die cast aluminum alloy articles have internal cylindrical surfaces such as the round internal cylinder surfaces of a cylinder block for an internal combustion engine. During casting solidification molten aluminum alloys shrink against the metallic permanent mold tools used to mold and define such internal surfaces, and tend to stick to the tool surfaces making it difficult to remove the casting. The tendency of some aluminum casting alloys to solder to the tool can further intensify sticking. In this invention, an aluminum alloy sleeve is placed on and over the tool surface before casting and the sleeve isolates the tool from the molten aluminum. The sleeve becomes bonded to the casting and facilitates removal of the casting from the tool. The sleeve may be (and preferably is) fully machined from the internal casting surface. The sleeve may be of the same composition as the casting, in which case handling and recycling of machining chips would be facilitated.

Abstract: A method for forming an aperture includes stamping an aperture into the article using a pellet, and refining aperture shape(s) and/or aperture dimensions. Methods for forming articles having reduced residual compressive stress are also disclosed. Very generally, the methods include establishing a diamond coating on at least a portion of a substrate, and applying a stress-relief process to the diamond coating, the substrate, or combinations thereof.

Abstract: An adaptive tire employable by a vehicle traveling upon a surface, including a releasable element operable to selectively modify a performance characteristic of the tire, such as traction, and methods of enhancing the performance of a tire by selective introduction of a substance.

Abstract: In substantial volume production operations involving hot blow forming or hot stamping of aluminum alloy sheet workpieces, debris largely comprised of particles of aluminum alloy material adheres to critical forming surfaces of the heated steel tools. This debris mars forming surfaces and causes defects in aluminum alloy parts formed against them. Such aluminum-rich debris may be reactively transformed to change its adherent properties and removed from tool surfaces without removing the heated tool from production. In one embodiment, a hot sacrificial magnesium sheet may be formed on the tool(s) to alloy with aluminum debris and carry it from the forming surface.

Abstract: A method that improves the formability of magnesium and magnesium tubes without altering the chemistry of such material or requiring changes to formation tooling. Magnesium or magnesium alloy sheet stock is subjected to at least one cycle of roll-forming deformation in a first direction followed by a reversal of roll-forming deformation and progressive development of a substantially circular cross-section. Lateral edges of the sheet are adjoined and the structure is thereafter heated above the recrystallization temperature.

Abstract: Double-action clinching includes establishing a first layer on a second layer, and securing the layers between a tool's punch and clinching punch. First layer has less ductility than second layer, and clinching punch diameter is smaller than punch diameter. Layers are secured so: a tool support receives a portion of a second layer surface; clinching punch, slidably positioned in the support, is adjacent another portion of the second layer surface; and punch, positioned opposed to clinching punch, is adjacent a portion of a first layer surface. Pressing the punch into the first layer surface portion forms an aperture through the first layer. Pressing the clinching punch, in a direction opposite to the punch pressing, into the other portion of the second layer surface forces portion(s) of the second layer into the aperture, and forms a micro-interlocking flush-back joint between an aperture side wall and the second layer portion(s).

Abstract: A method of clinching includes contacting a punch to stacked workpieces and rotating the punch to generate frictional heat in the workpieces, and advancing the punch into the workpieces to form a mechanically-interlocking joint. Rotation of the punch may be stopped prior to advancing the punch into the stacked workpieces. The first workpiece may be formed from a first material and the second workpiece formed from a different, second material. One of the first and second materials may be magnesium or a magnesium alloy. The mechanically-interlocking joint is characterized by the absence of intermetallic compounds, and may be substantially hermetically sealed against passage of fluids and gasses. A hole may be formed in one of the workpieces and, prior to contacting the punch to the workpieces, the hole aligned substantially coaxially with the punch. Forming the mechanically-interlocking joint may include deforming both the first and second workpieces.

Abstract: A clinching method includes establishing a first layer on a second layer. The first layer has an aperture formed therein and is thinner than the second layer. A rotating punch is engaged with the second layer through the aperture in the first layer, thereby generating frictional heat and softening the second layer. The rotating punch is configured with at least a first diameter, a shoulder, and a second diameter that is larger than the first diameter. The rotating punch is pressed into the softened second layer, thereby causing at least some of the second layer to: back extrude through an annulus defined by the aperture in the first layer and at least one of the diameters of the punch; contact the shoulder of the rotating punch; and extend onto a surface of the first layer adjacent the aperture.

Abstract: Magnesium and other metal alloy sheet materials are deformed at hot forming temperatures into vehicle body panels and other articles. Many such hot forming operations are improved in speed and product quality by predetermining a static recrystallization temperature of the sheet material. As the sheet material is being heated to its hot forming temperature, deformation is commenced below the static recrystallization temperature. As heating and deformation are continued, dynamic recrystallization of the workpiece occurs and deformation may proceed faster and to a greater extent.

Abstract: The formability of coiled and annealed (O-temper) magnesium alloy sheet material in high temperature forming operations is sometimes adversely affected by small amounts of cold work introduced into the fine grained material during handling of the coil and unwinding it to obtain blank workpieces for hot stamping, hot blow forming, or the like. When necessary, the formability of the sheet material with regions of hard worked microstructure may be improved by predetermining a recovery heat treatment using small portions of the material in formability tests. The recovery heat treatment, determined for the specific coiled stock, may then be applied to the material of the coil as it is used in making vehicle body panels or the like.

Abstract: Some die cast aluminum alloy articles have internal cylindrical surfaces such as the round internal cylinder surfaces of a cylinder block for an internal combustion engine. During casting solidification molten aluminum alloys shrink against the metallic permanent mold tools used to mold and define such internal surfaces, and tend to stick to the tool surfaces making it difficult to remove the casting. The tendency of some aluminum casting alloys to solder to the tool can further intensify sticking. In this invention, an aluminum alloy sleeve is placed on and over the tool surface before casting and the sleeve isolates the tool from the molten aluminum. The sleeve becomes bonded to the casting and facilitates removal of the casting from the tool. The sleeve may be (and preferably is) fully machined from the internal casting surface. The sleeve may be of the same composition as the casting, in which case handling and recycling of machining chips would be facilitated.

Abstract: Magnesium and other metal alloy sheet materials are deformed at hot forming temperatures into vehicle body panels and other articles. Many such hot forming operations are improved in speed and product quality by predetermining a static recrystallization temperature of the sheet material. As the sheet material is being heated to its hot forming temperature, deformation is commenced below the static recrystallization temperature. As heating and deformation are continued, dynamic recrystallization of the workpiece occurs and deformation may proceed faster and to a greater extent.

Abstract: The elevated temperature forming of magnesium based alloy workpieces by stretching, drawing, bending (or the like) a surface of the heated workpiece over the forming surface of a forming tool is improved by forming an integral adherent layer of magnesium hydroxide on the tool-contacted surface(s) of the magnesium alloy workpiece. The magnesium hydroxide layer may be formed by treating the surface(s) of the sheet with an aqueous salt solution (e.g., sodium chloride) at a temperature and for a time to form a protective layer of desired thickness (e.g., up to about thirty micrometers). If desired, an additional layer of forming lubricant, such as a film comprising boron nitride, may be applied to the magnesium hydroxide layer.

Abstract: The invention provides a method for manufacturing an automotive component member, including the steps of: (A) positioning at least one insert into a mold, wherein the insert defines a plurality of holes; and (B) casting a portion of the automotive component member in the mold to substantially encapsulate the insert such that a major portion of the insert is substantially non-bonded with the casting material to provide a proper interfacial boundary with the casting material for damping. The method may include the step of coating the insert to prevent bonding between the insert and the casting material. A damped automotive component member having an insert cast therein is also disclosed.