A continuous feed method for friction stir processing includes continuously feeding a tubular material having a first grain microstructure from a bulk source into a processing chamber, and forcing the tubular material between a die and a textured end portion of a mandrel as the tubular material is advanced through the chamber. The continuous feed method further includes rotating the mandrel within the tubular material while forcing the tubular material across the textured end portion to friction stir process the tubular material and transform a structure of the tubular material from the first grain microstructure to a second grain microstructure. The second grain microstructure is a finer equiaxed grain microstructure than the first grain microstructure. The method further includes converting the tubular material having the second grain microstructure into a stiffened sheet form.

A low-temperature joining method effectively suppresses reductions in the mechanical properties of a junction of various types of high-tensile steel or aluminum, and of a heat-affected zone; and produces a joint structure. A method for joining two metal materials by forming a joint interface in which the two metal materials face each other at a joint portion and plunge a rotation tool caused to rotate at a prescribed speed into the joint, the method for low-temperature joining of metal materials characterized in that the peripheral velocity of the outermost periphery of the rotation tool is set to 51 mm/s or less, whereby the recrystallization temperature inherent to the metal materials is reduced by introducing a large strain to the joint, and recrystallized grains are generated at the joint interface by setting the joining temperature to less than the recrystallization temperature inherent to the metal materials.

A friction welding apparatus is provided, which includes a tool, a rotary driver, a linear driver, and a control device. The control device controls the linear driver and the rotary driver so that the tool is rotated while a tip-end part thereof is pressed against a to-be-joined part of a to-be-joined object to increase a temperature of the to-be-joined part at or above an A1 transformation point, the tip-end part of the tool reaches a given first position so that a softened second member sticks into a softened first member, and the tool is drawn out from the to-be-joined part while the tool is rotated.

Disclosed are rotating tools for double-sided friction stir welding that are applied to double-sided friction stir welding, which is a technique for welding two metal plates by rotating a pair of rotating tools, which oppose each other, in opposite directions, a double-sided friction stir welding apparatus that uses the rotating tools, and a double-sided friction stir welding method. A pair of rotating tools for double-sided friction stir welding that are used in double-sided friction stir welding, which is a technique for welding metal plates by using a pair of rotating tools that are each disposed on one of first and second surfaces of an unwelded portion of the metal plates such that the rotating tools rotate in opposite directions, include end portions each of which is formed in a circular and planar shape. The end portions are each made of a material harder than the metal plates.

A method for manufacturing a liquid-cooling jacket (1) where heat transfer fluid flows in a hollow part (14) defined by a jacket body (2) and a sealing body (3) includes: an overlapping process in which the sealing body (3) is placed on an end surface (11a) of a peripheral wall part (11) in such a way that the end surface (11a) and a back surface of the sealing body (3) are overlapped each other to form a first overlapped part (H1); and a primary joining process in which primary joining is performed by friction stirring in such a way that a rotary tool (FD) is moved once around a recessed part (13) along the first overlapped part (H1). In the primary joining process, in a state where a base side pin of the rotary tool (FD) is in contact with the sealing body (3), a flat surface of the base (tip) side pin is brought in contact with only the sealing body (3), and a tip of a projection projecting from the flat surface is inserted more deeply than the first overlapped part (H1) to join the first overlapped part (H1).

A method for manufacturing a liquid-cooling jacket (1) where heat transfer fluid flows in a hollow part (14) defined by a jacket body (2) and a sealing body (3) includes: an overlapping process in which the sealing body (3) is placed on an end surface (11a) of a peripheral wall part (11) in such a way that the end surface (11a) and a back surface of the sealing body (3) are overlapped each other to form a first overlapped part (H1); and a primary joining process in which primary joining is performed by friction stirring in such a way that a rotary tool (F1) is moved once around a recessed part (13) along the first overlapped part (H1). In the primary joining process, the first overlapped part (H1) is joined in a state where the tip side pin is in contact with only the sealing body (3) or with the jacket body (2) and the sealing body (3) while the base side pin is in contact with the sealing body (3).

A tool head assembly for a solid state additive manufacturing apparatus includes a tool head having a material passage configured to receive a material therein. The tool head is configured to deposit the material from the material passage onto a substrate of the solid state additive manufacturing apparatus to form at least one layer of the material on the substrate. The tool head includes a shoulder configured to contact the material such that rotation of the tool head frictionally stirs the material. The tool head assembly includes a barrier configured to extend along a side surface of the at least one layer as the at least one layer is deposited onto the substrate such that the barrier is configured to constrain the material from extruding past an edge of the shoulder.

The present invention is characterized by including a primary joining process to perform friction stirring to a first butted portion by moving a stirring pin one round around a sealing body with a predetermined depth along a set moving track set at an inner position relative to an outer peripheral side face in a state that only the stirring pin of a rotary tool being rotated is inserted into the sealing body and that an outer circumferential face of the stirring pin is slightly in contact with a step side face of a peripheral wall step portion. In the primary joining process, after only the stirring pin being rotated is inserted into a starting position set at a position on an inner side relative to the set moving track, the stirring pin is gradually inserted to the predetermined depth while an axis of the rotary tool is moved to a position on the set moving track.

A friction stir welding apparatus that includes a rotary tool and a heating device. The heating device is placed in front of the rotary tool to heat steel sheets that are used as a workpiece. The rotary tool is moved in the welding direction so that steel sheet is softened by frictional heat. Additionally, the surface temperature, the area, and the position of the heated region during the heating process are strictly controlled. The heating of the steel sheets by the welding apparatus provides sufficient strength and good welding workability by advantageously eliminating plastic flow defects generated due to insufficient heating of workpieces.

A friction stir spot welding method includes a welding step of performing friction stir spot welding of a workpiece by using a pin member and a shoulder member while the workpiece is supported and pressed by the end face of a clamp member and a pressing step of causing a friction stir spot welding device to press an obverse surface and a reverse surface of at least one of a friction-stirred region of the workpiece and an adjacent region adjacent to the friction-stirred region of the workpiece from a rotary tool side and an opposite side after the welding step while the pin member and the shoulder member are accommodated in an accommodation space of the clamp member.