A friction stir spot welding apparatus includes: a pin that is columnar; a shoulder that is cylindrical, the pin being within the shoulder; a rotary driver that rotates the pin and the shoulder about an axis that coincides with a center axis of the pin; and an advance-retreat driver that advances and retreats the pin and the shoulder along the axis. A first groove is formed at a tip end portion of an outer peripheral surface of the shoulder so as to extend in a direction along the center axis of the pin.

A refill friction stir spot welding tool comprises: a clamp; a shoulder concentric with, and articulable relative to, the clamp; and a probe concentric with, and articulable relative to, the shoulder; wherein each of the clamp, the shoulder and the probe have at least a portion made of a superabrasive material.

A method for attaching a cover to a base includes coupling the cover to the base and welding the cover to the base using a friction stir welding tip. The method further includes pushing the cover against the base using a shoulder through which the friction stir welding tip extends.

A friction stir welding apparatus includes a welding tool that includes a shoulder and a probe supported by the shoulder, is inserted into a plurality of welding target members, and moves while rotating to weld the plurality of welding target members, a spindle motor that is coupled to the welding tool to rotate the welding tool in a predetermined direction, a welding head that supports the spindle motor, and an apparatus body that supports the welding head, applies a drive signal to the spindle motor, and moves the welding tool along a welding line while rotating the welding tool. The apparatus body has a first correction mode in which a welding tool position indicating a position of the welding tool in a Z-axis direction is corrected based on a variable correction quantity calculated by a predetermined operational expression according to a fluctuation quantity of a state quantity indicating a control quantity of the welding head in a Z-axis upper direction or a Z-axis lower direction when friction stir welding is performed on the welding target members by the welding tool, and a second correction mode in which the welding tool position is corrected based on a preset fixed correction quantity according to the fluctuation quantity.

A friction stir welding tool includes a probe having a front end surface and an outer circumferential surface. Outer circumferential recesses are formed in the probe. The outer circumferential recesses extend along the rotational axis of the probe up to the front end surface. The friction stir welding tool rotates the probe about the rotation axis, and embeds the probe inside a workpiece during rotation of the probe to weld the workpiece. A front end recess is formed in the front end surface. The front end recess is positioned at the central part of the front end surface, and connected to the outer circumferential recesses.

A friction stir welding tool includes a probe having a front end surface and an outer circumferential surface. The probe has, formed therein, outer circumferential recesses extending to the front end surface along a rotation axis. The friction stir welding tool rotates the probe about the rotation axis and embeds the probe inside a workpiece during rotation of the probe to thereby weld the workpiece. The width of the outer circumferential recesses is increased toward a front end of the probe.

A double-acting tool for friction stir spot welding is used to weld a first member and a second member each formed of a thermoplastic resin molding by friction stir spot welding. An overlapping part of the first member and the second member is formed, and the tool is disposed against the overlapping part while rotating a pin and a shoulder about a rotation axis. The shoulder is plunged into the overlapping part to start friction stir. The plunging is continued until the shoulder penetrates the first member, and penetrates the second member or reaches a depth corresponding to a first thickness t1 or lager. Subsequently, the overlapping part is backfilled with a resin material overflowed due to the plunging.

A deburring tool for cutting burr generated when members are welded to each other by friction stir welding is provided. The deburring tool includes a tool center portion contacting a welding portion, and a blade portion formed on an outer circumference of the tool center portion to cut the burr. The tool center portion includes a protrusion protruding downward from a ridge line of the blade portion to control a burr cutting amount.

A method of friction-stir welding, FSW, a joint J, for example a T joint and/or a lap joint, between a first workpiece W1 and a second workpiece W2, is described. The method comprises: performing a first pass P1 of FSW of the joint J by moving therealong a first tool (10), comprising a first probe (100) rotating in a first rotational direction RD1, in a first movement direction MD1 defining a first line L1, on a first side S1 of the joint J, comprising: inserting the first probe (100) to a first depth D1, thereby providing a first welded region WR1; withdrawing at least partially the first probe (100), thereby providing a first partially welded and/or unwelded region PWUR1; and fully withdrawing the first probe (100), thereby resulting in a first exit hole EXH1; performing a second pass P2 of FSW of the joint J by moving therealong a second tool (20), comprising a second probe (200) rotating in a second rotational direction RD2, in a second movement direction MD2 defining a second line L2, on the first side S1 of the joint J, comprising: inserting the second probe (200) to a second depth D2, thereby providing a second welded region WR2; optionally withdrawing at least partially the second probe (200); and fully withdrawing the second probe 200, thereby resulting in a second exit hole EXH2; wherein the second welded region WR2 includes the first exit hole EXH1; and wherein the second exit hole EXH2 is included in the first welded region WR1.

This disclosure relates to a tool assembly for friction stir welding. The tool assembly comprises a tool holder and a puck each having an axis of rotation. The tool holder comprises a tool post and the puck comprises a pin. The puck is coupled to the tool post. The tool assembly is adapted such that during friction stir welding, run-out of the tool holder, measured as the run-out between the axis of rotation of the tool holder and the axis of rotation of the pin, does not exceed 10 μm.