A tool for friction bit joining a workpiece material includes a bit with a tapered pin and a non-cutting tip. The bit has a top surface opposite the pin with at least one feature recessed in, or extending from, the top surface and configured to transmit torque to the bit to rotate the bit around a rotational axis.

The method of friction stir spot welding uses a database of stored optimization parameters to maximize welding strength for an input type of material and an input geometrical parameter of the material, such as its thickness. Experiments are performed for a variety of different materials having different thicknesses. Each experiment performed for each material and each thickness associated with the material measures the welding strength of a friction stir spot welding process for varying values of an initial dynamic welding parameter, a final dynamic welding parameter and a type of varying function. The values of the initial dynamic welding parameter, final dynamic welding parameter and type of varying function that maximize the measured welding strength for the selected material and its selected thickness are stored in a lookup table. A rotating tool may then be controlled using these optimized values in order to maximize welding strength.

A friction stir welding tool (1) has a shoulder portion (2) and a probe portion (6) provided on a bottom surface of the shoulder portion (2). The probe portion (6) has a length of 5.5 mm or more. In the friction stir welding tool (1), a ceramic material whose main phase is silicon nitride or sialon is used as a base material.

A heat exchanger is disclosed. The heat exchanger includes a heat exchange member that includes a first extruded member having a first end and a second end. The first extruded member forms a plurality of fluid passages that are in fluid communication with the first end of the first extruded member and the second end of the first extruded member. At least one of the fluid passages is an inlet fluid passage and at least one of the fluid passages is an outlet fluid passage. A plug is fixedly coupled to the second end of the first extruded member. The plug forms a plug fluid passage that fluidically interconnects the inlet fluid passage at the second end of the first extruded member with the outlet fluid passage at the second end of the first extruded member.

A system, apparatus, or method for joining components is provided. The system applies force along an axis, with a friction pin, to a first substrate, such as with a joiner or joining apparatus. The system also frictionally melts a portion of the first substrate adjacent the friction pin by rotating the friction pin about the axis at a first speed within the first substrate. The system also applies force to the second substrate along the axis and frictionally melts a portion of the second substrate adjacent the friction pin by rotating the friction pin at a second speed within the second substrate. The system embeds a portion of the friction pin within the first substrate and the second substrate. In some configurations, the first speed and the second speed are substantially equivalent. In other configurations, the first speed is different from the second speed.

Disclosed herein are systems, methods, and devices for repairing holes in weld seams created by bobbin friction stir welding tools. A hole may be created when a welding tool or, more specifically, a pin of the tool is removed or otherwise extracted from a weld seam created by the tool. The method may involve inserting a plug (e.g., a rivet) into the hole, reshaping the plug in the hole (e.g., riveting) thereby securing the plug in the component, and creating another weld seam through the plug thereby consuming the plug. In some embodiments, the hole may be reshaped prior to inserting the plug. For example, the hole may be drilled out and/or a countersink may be created on one or both ends of the hole. Furthermore, the plug may extend outside of the hole prior to its reshaping and, in some embodiments, even after reshaping.

A friction stir spot welding device includes a pin member, a shoulder member, a rotation driving unit, a tool driving unit, a position detector, and a controller, wherein the controller sets as reference position of the tip end surface of the pin member or shoulder member at a time point when the pin member tip end surface or shoulder member contacts an obverse surface of an object and controls the tool driving unit reducing a pressing force to the object by the pin member and pressing force to the object by the shoulder member in a next welding process, and/ or controls the rotation driving unit reducing the pin member rotational speed and shoulder member rotational speed in the next welding process, in case where a first position is the position of the tip end surface of the pin member or the shoulder member is within a first region.

Apparatus and method for increasing the quality of the weld seam in friction stir welding, with the following features: a) a receiving plate (1) with a drive head (2), the latter having a receiving flange (19) for receiving a holding bell (3) connected by means of a union nut (7) to a welding shoe (4) with a welding pin tip (5), b) the welding shoe (4) has a circular basic shape, on which there is a transverse web running over the cross section and rising at a right angle to said basic shape, said transverse web having a width of approximately to of the diameter of the basic shape and having an arc-shaped shoe sliding surface and shoe smoothing surface (9), c) the welding pin tip (5) has substantially a surface structure in the form of a tapering thread, this thread-like structure not being arranged in a purely circular manner.

Solid-state joining of preformed features, such as bosses, flanges, gaskets, centralizers and other features to substrates or cast parts by a solid-state MELD 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 friction stir welding apparatus includes a FSW tool that is held by a housing and welds to-be-welded members to each other by friction stir, and a gradual cooling device that gradually cools a weld site of the to-be-welded members welded by the FSW tool. The gradual cooling device is a contactless heat source that heats the weld site without coming into contact with the weld site. The contactless heat source is a high-frequency heat source.