A liquid cooling jacket is produced by forming a first butted portion where a step side face of a peripheral wall portion and an outer peripheral side face of a sealing body butt each other and a third butted portion where a step side face of a support pillar portion and a hole wall of the hole portion of the sealing body portion butt each other with a gap, and friction-stirring by inserting a tip side pin and a base side pin of a primary joining rotary tool that is rotating into the sealing body and moving the primary joining rotary tool along the third butted portion with an outer circumferential face of the tip side pin being kept off the step side face while having a second aluminum alloy of the sealing body flow into the gap.

A friction stir spot welding apparatus includes a pin member formed in a solid cylindrical shape, a shoulder member formed in a hollow cylindrical shape, the pin member being inserted in the shoulder member, a rotary actuator that rotates the pin member and the shoulder member on an axis that is in agreement with an axial center of the pin member, and a linear actuator that linearly moves each of the pin member and the shoulder member along the axis. A tip-end part of the shoulder member is formed in a tapered shape.

A friction stir spot welding apparatus including a controller that (A) operates a rotary driver and a tool driver such that a pin and a shoulder are brought into contact with a welded workpiece; (B) operates, after the step (A), the rotary driver and the tool driver such that the pin separates from the welded workpiece; and (C) operates, after the step (B), the rotary driver and the tool driver such that the pin advances toward the welded workpiece. The controller controls the tool driver such that pressing force applied to the welded workpiece from the pin and the shoulder in the step (C) is smaller than that in the step (B) and/or controls the rotary driver such that rotational frequencies of the pin and the shoulder in the step (C) are lower than those in the step (B).

A transmission shaft of a countershaft-type manual transmission is constructed from a plurality of hollow shaft portions which are butt press welded to one another, at least two of which hollow shaft portions are provided in each instance with at least one helical toothing of a fixed wheel of a spur gear stage. The hollow shaft portions provided with a helical toothing are connected to the respective adjacent hollow shaft portion in each instance so as to be rotated by a correction angle (Δα) around their center axis in proportion to a deviation (Δx) from their axial target position, wherein the ratio between the correction angle (Δα) and the axial deviation (Δx) corresponds to the pitch (s) of the helical toothing (Δα/Δx=s).

A method of joining a first component to a second component at respective connection surfaces, comprising, in order, applying a local surface treatment to the connection surface of at least one of the first and second components in order to locally alter the microstructure to a depth of between 60 μm and 10 mm below the connection surface; and joining the first component to the second component using a welding process.

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 makes it possible to weld workpieces to each other efficiently firmly by friction stir welding while reducing labor and man-hours. A friction stir welding method includes a fixing step, a temporary welding step S2, and a main welding step as follows. The fixing step includes fixing the workpieces W1 and W2 to a receiving table by pressing the workpieces W1 and W2 against the receiving table by means of a plurality of spring pins 10 that, are spaced apart from one another. The temporary welding step S2 includes spot-welding the workpieces W1 and W2 to each other by friction stir welding at locations different from positions of the spring pine 10. The main welding step includes line-welding the spot-welded workpieces W1 and W2 to each other by friction stir welding.

A friction stir spot welding apparatus according to the present invention includes: a rotary tool; and a perpendicular-to-plane detector, which detects whether or not the rotary tool is positioned to be in a perpendicular-to-plane state relative to a joining target portion of workpieces. The perpendicular-to-plane detector measures distances to at least three measurement positions set around the joining target portion by means of, for example, position sensors. The measurement positions are set to be positioned at the vertices of a polygon on a reference plane to which forward and backward movement directions of the rotary tool are normal. The perpendicular-to-plane detector detects that the rotary tool is positioned to be in the perpendicular-to-plane state relative to the joining target portion of the workpieces if all the distances to the measurement positions are equal to each other.

A friction stir spot welding apparatus includes a pin member, a shoulder member, a rotation driver, a forward/backward movement driver, and a controller. The controller controls the forward/backward movement driver, such that the pin member and/or the shoulder member press workpieces before a clamp member presses the workpieces, and then controls the rotation driver and the forward/backward movement driver, such that the pin member and the shoulder member stir the workpieces.

A retaining device (3) is provided for a workpiece (7), which is machined by an industrial robot (2), including a machining tool (4), along a machining path (16). The retaining device (3) includes a clamping tool (5) for clamping tool parts (13, 14) on the machining path (16) and a multi-axis guiding device (6) for the clamping tool (5) and for the independent movement thereof relative to the workpiece (7) during the machining process.