A method for determining a quality of a friction stir welded seam is described. The method involves applying an impact to a welded plate and comparing its damping capacity with the damping capacity of a geometrically equivalent defect-free plate. Damping capacities that differ by a small percent difference indicate that the welded plate is also defect-free. This method is particularly advantageous when dealing with small defects, which produce miniscule changes in natural frequency which may not be measureable.

A method for determining a quality of a friction stir welded seam is described. The method involves applying an impact to a welded plate and comparing its damping capacity with the damping capacity of a geometrically equivalent defect-free plate. Damping capacities that differ by a small percent difference indicate that the welded plate is also defect-free. This method is particularly advantageous when dealing with small defects, which produce miniscule changes in natural frequency which may not be measureable.

Solid-state joining of preformed features, such as bosses, flanges, gaskets, centralizers and other features to substrates or cast parts by a solid-state additive manufacturing process is disclosed. Joining can be between same or different materials using same, similar or dissimilar filler material than the materials of the feature and the part that need to be joined.

A method of forming a stamped part includes forming a tailor welded blank by friction stir welding (FSW) a first blank to a second blank, removing a FSW start spot and a FSW stop spot from the tailor welded blank using a machining process such that a finished tailor welded blank is formed and stamping the finished tailor welded blank into the stamped part such that a weld formed by FSW the first blank to the second blank is plastically deformed. The first blank and the second blank can be aluminum alloy blanks and a predetermined amount of material is machined from the FSW start spot and the FSW stop spot, the predetermined amount of material being equal to or greater than a thickness of the first blank and the second blank.

A method for detecting a surface welding quality of friction stir welding includes: acquiring a continuous surface depth image of a welding seam; intercepting a surface depth image segment of the welding seam with a proper step size, and dividing the intercepted surface depth image segments of the welding seam into a front reference region, a thinned region and a rear reference region; judging whether flatness of the front reference region is less than a threshold, and if yes, taking a height of the front reference region at this point as a latest reference height; if no, judging whether the flatness of the rear reference region is less than the threshold, and if yes, taking a height of the rear reference region at this point as the latest reference height; if no, taking the reference height of previous depth image segment as the latest reference height; and calculating a difference.

A technique for creating a weld along a joint. A method begins by positioning a first edge of a first member proximate to a second edge of a second member to form the joint, wherein the joint is to be welded along the length from a first position on the joint to a second position on the joint. A clamping ring of a refill spot welding apparatus is placed to surround an unwelded portion of the length. The clamping ring contacts a top surface of the first member and a top surface of the second member. A first refill spot weld process is performed with the refill spot welding apparatus to join the first member and the second member at a first spot weld on the joint.

A method for determining a quality of a friction stir welded seam is described. The method involves applying an impact to a welded plate and comparing its damping capacity with the damping capacity of a geometrically equivalent defect-free plate. Damping capacities that differ by a small percent difference indicate that the welded plate is also defect-free. This method is particularly advantageous when dealing with small defects, which produce miniscule changes in natural frequency which may not be measureable.

A method for determining a quality of a friction stir welded seam is described. The method involves applying an impact to a welded plate and comparing its damping capacity with the damping capacity of a geometrically equivalent defect-free plate. Damping capacities that differ by a small percent difference indicate that the welded plate is also defect-free. This method is particularly advantageous when dealing with small defects, which produce miniscule changes in natural frequency which may not be measureable.

A method for determining a quality of a friction stir welded seam is described. The method involves applying an impact to a welded plate and comparing its damping capacity with the damping capacity of a geometrically equivalent defect-free plate. Damping capacities that differ by a small percent difference indicate that the welded plate is also defect-free. This method is particularly advantageous when dealing with small defects, which produce miniscule changes in natural frequency which may not be measureable.

A method of manufacturing a liquid-cooled jacket, includes a preparation step which includes placing a sealing body on a stepped portion to allow a step side surface and a sealing-body side surface of the sealing body to butt each other, and a primary joining step which includes allowing a primary joining rotary tool to move once around the sealing body, while moving the rotary tool along a butted portion formed in the preparation step, to carry out friction stir welding. The primary joining step includes employing the primary joining rotary tool provided with a stirring pin having a length dimension greater than a thickness dimension of the sealing body, and carrying out friction stirring with only the stirring pin being brought into contact with a jacket body and the sealing body.