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 friction stir welded assembly includes a first workpiece having an interior portion with opposed interior walls, a second workpiece having an interior portion with opposed interior walls, and an insert positioned within the interior portion of the first workpiece and the interior portion of the second workpiece. The insert extends between and abuts at least one of the opposed interior walls of the first workpiece and the opposed interior walls of the second workpiece and a friction stir weld is between the first workpiece to the second workpiece. A joining end of the first workpiece and a joining end of the second workpiece form a butt joint or a lap joint between the first and second workpieces, and the friction stir weld is a butt weld or a lap weld, respectively, between the first and second workpieces.

A primary joining rotary tool F comprises a stirring pin F2including a circumferential face tapers to become thinner toward a tip portion of the stirring pin, a flat face F3 at the tip portion of the stirring pin F2 and a projecting portion F4 projecting from the flat face F3. Friction-stirring is performed in the primary joining process by inserting the stirring pin F2 that is rotating into an abutted portion J1 in a manner that only the stirring pin F2 is in contact with the base member 2 and the lid plate 5 with the flat face F3 being in contact with the base member 2 and the lid plate 5 and with a tip face F5 of the projecting portion F4 being in contact only with the base member 2.

Solid-state additive manufacturing processes for joining dissimilar materials and parts are described. Processes include feeding a first material through a hollow tool of a solid-state additive manufacturing machine to contact a second material, generating deformation of the materials by applying normal, shear and/or frictional forces using a rotating shoulder of the tool such that the materials are in a malleable and/or visco-elastic state in an interface region, and mixing and joining the materials in that region. The joining can include interlocks of various shapes in the interface region. One or multiple taggants can be included in deposited material and/or layers, which taggants respond when triggered by specific external stimulus, such as becoming visible upon subjecting to light of a particular wavelength, heating, electric field, and so on. Some taggants are capable of multiple levels of security effects which can be seen by the naked eye or by using special detectors/readers.

An additive manufacturing system for depositing an extrudate onto a substrate comprises a deposition head. The deposition head comprises a stirring tool, rotatable about an axis of rotation AR and comprising a tool distal end and a tool proximal end, axially opposing the tool distal end along the axis of rotation AR. The stirring tool defines a bore, extending from the tool proximal end to the tool distal end. The bore is configured to receive feedstock, biased toward the tool distal end. The deposition head also comprises a die, which is positioned adjacent to the stirring tool, defines a die axis AD1, and comprises a die distal end and a die proximal end, axially opposing the die distal end along the die axis AD1. The die axis AD1 is parallel with the axis of rotation AR of the stirring tool.

A device for depositing a material layer on a surface of a workpiece has a deposition facility with a hollow shoulder that is rotatable about an axis relative to a base. The shoulder has an indentation that is limited by a circumferential annular face. A passage opening, which is smaller in diameter than the indentation, is formed in the shoulder along the axis. The shoulder is rotated and a deposition material is fed through the passage opening into the indentation where it is plasticized in the indentation. The deposition facility is moved over the surface in such a way that the indentation points towards the surface and a workpiece plane runs tangentially to the surface at the point at which the axis intersects the surface. The annular face is distanced from the surface such that plasticized deposition material is deposited on the surface. A related deposition method is also provided.

A method and apparatus for joining workpieces is described. The apparatus comprises a clamp configured to restrain a first workpiece against a second workpiece and an additive friction stir deposition (AFSD) machine comprising a spindle. The first workpiece is clamped to the second workpiece, and feedstock material is deposited, via rotation of the spindle, into an aperture extending through one or both of the first workpiece and the second workpiece. The deposited feedstock material forms a weld nugget that joins the first workpiece to the second workpiece.

A friction stir welding equipment according to an embodiment includes a spindle unit, a holder, and a moving part; the spindle unit is capable of rotating a tool; the holder is connectable to the tool via a radial bearing and is capable of holding at least one of a side surface of a processing member or a rim of an upper surface of the processing member; and the moving part is capable of changing relative positions of the tool and the holder with respect to the processing member.

A method is provided for manufacturing an article. The method comprises depositing by additive friction stir deposition a wear-resistant material on a surface of a preform to provide an intermediate article. The preform comprises a first composition and the wear-resistant material comprises a second composition. The second composition is substantially different from the first composition. The method also comprises machining the intermediate article to remove therefrom at least a portion of the wear-resistant material.

Welding methods and welded joints for improving corrosion resistance of the joint between a plurality of high-strength aluminum alloy structural members are described herein. An example method can include applying a first weld at a junction between the plurality of high-strength aluminum alloy structural members using a first filler metal, and applying a second weld on at least a portion of a toe of the first weld using a second filler metal. The second weld can be applied using a fusion welding process (e.g., an arc welding process or a high energy beam welding process). Additionally, the secondary weld can alter a secondary phase of the first weld.