Abstract: A system and method of joining at least two workpieces together using a friction rivet and a friction rivet cap that are friction stirred together after a cutting tip or cutting feature on the friction rivet cuts through workpieces and is then bonded to the friction rivet cap, and wherein the friction rivet cap may be excluded if the friction rivet includes a hollow in the cutting tip, the hollow being flared after the friction rivets cuts through the workpieces to thereby create an integral rivet cap in the end of the friction rivet.

Abstract: A system and method for modifying a work piece surface of high melting temperature materials such as Advanced High Strength Steels, wherein a friction stir welding tool may include cutting elements located on the outside diameter of a collar assembly, wherein the collar assembly may be retrofitted for existing friction stir welding tools, or may be designed as a custom attachment for a new hybrid friction stir welding tool, wherein the surface of the work piece may be modified by removing detrimental flash and burr created during operation of the friction stir welding tool.

Abstract: A system and method for modifying a work piece surface of high melting temperature materials such as Advanced High Strength Steels, wherein a friction stir welding tool may include cutting elements located on the outside diameter of a collar assembly, wherein the collar assembly may be retrofitted for existing friction stir welding tools, or may be designed as a custom attachment for a new hybrid friction stir welding tool, wherein the surface of the work piece may be modified by removing detrimental flash and burr created during operation of the friction stir welding tool.

Abstract: A mandrel that provides a counter-force to the pressure exerted on the outside of a pipe or other arcuate surface by a friction stir welding tool, wherein the mandrel is expandable through the use of a wedge, and wherein the mandrel enables multiple friction stir welding heads to simultaneously perform welding on the arcuate surface.

Abstract: A method is taught for creating a hollow sphere that is created by joining two cylinders together that have a semispherical hollow formed in the ends being joined together, wherein a metallic reinforcing disk is inserted at an interface between the two ends of the cylinders, wherein the two cylinders and reinforcing disk are joined using friction stir welding to create an inner sphere from the two hemispherical hollows that is bisected by the metallic reinforcing disk, and wherein the joined cylinders and reinforcing disk are machined to thereby create an outer spherical surface that is centered around the inner sphere.

Abstract: A control parameter ramp profile that enables control parameters to be modified in a non-linear manner, such that as a temperature set point of a tool or a weld is approached, the control parameter ramp profile enables the temperature set point to be approached in a manner that prevents temperature overshoot and therefore creating a better weld along the length thereof, wherein the control parameter ramp profile includes but is not limited to proportional, exponential or an S-curve waveform.

Abstract: A method is taught for creating a hollow sphere that is created by joining two cylinders together that have a semispherical hollow formed in the ends being joined together, wherein a metallic reinforcing disk is inserted at an interface between the two ends of the cylinders, wherein the two cylinders and reinforcing disk are joined using friction stir welding to create an inner sphere from the two hemispherical hollows that is bisected by the metallic reinforcing disk, and wherein the joined cylinders and reinforcing disk are machined to thereby create an outer spherical surface that is centered around the inner sphere.

Abstract: A tool is provided that is capable of friction stir processing, friction stir mixing, and friction stir welding of high melting temperature and low melting temperature materials, wherein the collar is now divided into at least an inner and an outer collar coupled to the shank and the FSW tip, wherein new thermal barriers enable expansion of the inner collar to be directed inward to thereby create compression on the FSW tip instead of allowing the FSW tip to become loose in the tool at elevated temperatures.

Abstract: A system and method for friction stir processing of a hand-held cutting edge, wherein friction stir processing techniques are used to modify the properties of the hand-held cutting edge to obtain superior edge retention and superior resistance to chipping of the hand-held cutting edge.

Abstract: A friction stir tool is provided to perform friction stir riveting using a partially consumable pin, wherein the pin includes a cutting edge on a bottom surface thereof, wherein the tool is rotated at a first speed to enable cutting by the pin into a first material that is overlapping a second material, wherein after the pin has cut to a sufficient depth, the rotational speed of the tool is increased to thereby enable plasticization of the consumable pin, the first material, and the second material, wherein the tool is then rapidly decelerated until stopped, enabling diffusion bonding between the pin, the first material and the second material.

Abstract: A method of selecting a geometry for a friction stirring tool, said tool having a melting point that is higher than the workpiece material, wherein the tool is placed in motion against the workpiece to generate heat in the workpiece such that workpiece material is transported in surface features of the tool, and wherein surface features manage workpiece material flow around the tool, and wherein the tool can be used in friction stir processing, friction stir mixing, friction stir welding, and friction stir spot welding of high melting temperature materials or high softening temperature materials.

Abstract: A probe for friction stir welding MMCs, ferrous alloys, non-ferrous alloys, and superalloys, as well as non-ferrous alloys, the probe including a shank, a shoulder, and a pin disposed through the shoulder and into the shank, wherein the pin and the shoulder at least include a coating comprised of a superabrasive material, the pin and shoulder being designed to reduce stress risers, disposing a collar around a portion of the shoulder and the shank to thereby prevent movement of the shoulder relative to the shank, and incorporating thermal management by providing a thermal flow barrier between the shoulder and the shank, and between the collar and the tool.

Abstract: A friction stir tool is provided to perform friction stir riveting using a partially consumable pin, wherein the pin includes a cutting edge on a bottom surface thereof, wherein the tool is rotated at a first speed to enable cutting by the pin into a first material that is overlapping a second material, wherein after the pin has cut to a sufficient depth, the rotational speed of the tool is increased to thereby enable plasticization of the consumable pin, the first material, and the second material, wherein the tool is then rapidly decelerated until stopped, enabling diffusion bonding between the pin, the first material and the second material.

Abstract: A new control variable is introduced, that when combined with previous dependent control criteria on other variables results in a control program that can create a superior weld while minimizing wear on the FSW tool, wherein the tool repeatedly experiences the same thermal and mechanical loading within specified control windows during every repeated weld sequence because flow stresses and tool loads are driven by temperature, and dependent control loops account for differences in material and heat that is transferred at different rates in varying locations throughout a friction stir weld.

Abstract: A friction stir tool is provided to perform friction stir riveting using a partially consumable pin, wherein the pin includes a cutting edge on a bottom surface thereof, wherein the tool is rotated at a first speed to enable cutting by the pin into a first material that is overlapping a second material, wherein after the pin has cut to a sufficient depth, the rotational speed of the tool is increased to thereby enable plasticization of the consumable pin, the first material, and the second material, wherein the tool is then rapidly decelerated until stopped, enabling diffusion bonding between the pin, the first material and the second material.