A friction stir welding method includes joining a first metal member, a second metal member, and a third metal member by pressing a tool onto a joining member while rotating the tool. The tool has a protrusion at a tip of the tool. The joining member includes the first metal member, the second metal member, and the third metal member. A major element of the second metal member is the same as a major element included in the first metal member. The third metal member is sandwiched between at least a portion of the first metal member and at least a portion of the second metal member. A major element of the third metal member is the same as the major element included in the first metal member and the second metal member. A crystal grain size of the third metal member is 20 μm or less.

A method for repairing a defect affecting a weld. A sheet of filler metal is placed on the surface of the welded part, next to the region of the defect. The sheet is locally welded to the welded part in the region of the defect using a friction stir welding tool having a retractable welding pin. The welded part and the sheet are separated such that the filler metal amalgamated with the metal of the welded part remains in position. The local welding operation includes successively performing the following: setting the welding tool into rotation and putting it under pressure; inserting the pin to a small distance from the anvil while maintaining or increasing the pressure on the shoulder of the welding tool; progressively retracting the pin while maintaining or increasing the pressure on the shoulder; and stopping the pressure on the shoulder when the retractable pin has been retracted.

A method includes the following: an incidence step in which ultrasonic waves from an insertion side and the side opposite thereto of a tool are caused to be incident on a joint part when a workpiece is joined by the tool that has a probe and a shoulder which supports the probe and that is for friction stir welding; an image acquisition step for obtaining an ultrasonic wave transmission image of the joint part using the ultrasonic waves; and a determination step for determining that the joint part has been joined if width-dimensions of the joint part obtained from the ultrasonic wave transmission image are equivalent to at least the outer diameter d of the probe and if no defect of a prescribed size or greater is found in a range equivalent to the outer diameter D of the shoulder or less in the ultrasonic wave transmission image.

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.

A method for fixing a strip end segment of a metal strip wound into a coil to a strip winding of the coil arranged adjacent to the strip end segment. In order to enable the production of metal strip with improved quality, the strip end segment is fixed by materially bonding on the strip winding by means of a friction welding method.

In a double-acting friction stir spot welding device or a double-acting friction stir spot welding method, a pin member and a cylindrical shoulder member that rotates around the axis of the pin member are used as rotary tools, and a clamp member that has a cylindrical shape positioned so as to surround the outside of the shoulder member and is configured to press a workpiece from an obverse surface with an annular pressing surface of the distal end is used as a holding jig. The clamp member has an inclined surface that is adjacent to the inner edge portion of the pressing surface and inclined so as to reduce the inner diameter of the clamp member toward the back side as viewed from the pressing surface.

An edge of each of a first metal member and a second metal member is formed to have a U-shaped cross section with a first horizontal plate projecting from a base edge of a vertical plate, and with a second horizontal plate projecting from a top edge of the vertical plate. The second metal member includes a projecting part. The joining method includes: an abutting step of forming an abutted part by abutting a front surface of the first horizontal plate the first metal member against a second side surface of the second metal member; and a joining step of performing friction stir welding of the first metal member and the second metal member by inserting a stirring pin from the projecting part and moving a joining rotating tool along an inner corner at the top edge of the vertical plate of the second metal member while making only the stirring pin in contact with the first metal member and the second metal member.

This invention is characterized by including: a primary joining process in which a coarse portion having a predetermined width is formed in the vicinity of a step side face within a plasticized region while a rotary tool is being moved one round along a first butted portion to perform friction stirring in a state that a tip of a stirring pin of the rotary tool which is rotated is inserted to the same depth as or slightly deeper than the step bottom face and only the stirring pin is slightly in contact with at least an upper portion of a jacket body; and an inspection process in which a passed position of the stirring pin is specified by performing a defect inspection to detect the coarse portion after the primary joining process.

A joint structure includes a first sheet member, a second sheet member, a third sheet member, and plural joining parts formed at locations where the first sheet member, the second sheet member, and the third sheet member overlap, so as to join the first sheet member, the second sheet member, and the third sheet member together. The plural joining parts are formed at an interval along an edge of the first sheet member and an edge of the second sheet member. The third sheet member includes a fold-back portion provided at least between the plural joining parts by folding the third sheet member back around the edge of the first sheet member and the edge of the second sheet member such that the fold-back portion is disposed on an opposite side of the first sheet member from a side overlapped with the second sheet member.

The disclosure provides an aluminized composite including a base material. The aluminized composite may also include a diffusion layer disposed over the base material. The aluminized composite may further include an aluminum material disposed over the diffusion layer.