A process for joining fiber composite materials using self-piercing rivets. The process includes contacting first and second panels. The second panel is a fiber composite material. The process further includes elevating a temperature of only a fastening portion of the second panel. The process also includes placing the first and second panels on a die and joining the first and second panels with one or more rivets while the fastening portion is at an elevated temperature.

A two-part mechanical fastener comprising an elongated body with a bore slidably carrying a mandrel adapted to interferingly engage the body is described. The fastener body has one or more protuberances on its exterior surface. In an aspect, the protuberances form a thread. The fastener is adapted to form an opening in, and penetrate, a stack of two or more workpieces. To secure the workpieces in the workpiece stack and form a robust joint, the fastener body is deformed by the mandrel, expanding the body, so that a body end engages a surface of the workpiece stack and the one or more protuberances are brought into engagement with the walls of the opening. Methods of using such a fastener to secure non-ferrous or polymer-based sheet-like workpieces to one another are disclosed.

Composite fasteners, associated blanks and also methods and apparatus for the installation of such fasteners are disclosed. An exemplary composite rivet disclosed comprises an elongated body including braided reinforcement fibers embedded inside the body and supported in a matrix material. Also disclosed are structural assemblies comprising composite fasteners and panels or other parts comprising composite and/or other materials.

A riveting system, for use in mechanically linking adjacent workpieces, including a rivet having a height greater than a sum of thicknesses, measured along a line of riveting, of the workpieces being linked, so that the rivet can pass fully through the workpieces. The system also includes a riveting die, which may be a separate product. The die includes a protrusion extending from a peak toward a transition point; and a trough having a trough surface. The trough surface includes a trough inner wall, extending from the transition point to a trough bottom, and a trough outer wall, extending from the trough bottom to a trough outer edge. The technology also includes computerized systems for comparing a load-displacement profile of riveting to a pre-set profile to determine whether the riveting was performed properly.

A method of bonding a connector to a first object includes providing the connector, the connector being separate from the first object and including a thermoplastic material; arranging the first object and the connector relative to one another so that the connector reaches from a proximal side of the object through a first opening in the object; generating and applying vibrations and mechanical pressure to the connector until a flow portion of the thermoplastic material is liquefied and caused to flow sideways radially into an open space; and removing the source of the vibrations and causing the liquefied thermoplastic material to re-solidify, resulting in the connector with a foot portion, a head portion, and a shaft portion between the foot portion and the head portion. The shaft portion extends along an axis through the first opening, and secures the connector to the first object.

Composite fasteners, associated blanks and also methods and apparatus for the installation of such fasteners are disclosed. An exemplary composite rivet (10) disclosed comprises an elongated body including braided reinforcement fibers (14) embedded inside the body and supported in a matrix material (16). Also disclosed are structural assemblies comprising composite fasteners and panels or other parts comprising composite and/or other materials.

A riveting system, for use in mechanically linking adjacent workpieces, including a rivet having a height greater than a sum of thicknesses, measured along a line of riveting, of the workpieces being linked, so that the rivet can pass fully through the workpieces. The system also includes a riveting die, which may be a separate product. The die includes a protrusion extending from a peak toward a transition point; and a trough having a trough surface. The trough surface includes a trough inner wall, extending from the transition point to a trough bottom, and a trough outer wall, extending from the trough bottom to a trough outer edge. The technology also includes computerized systems for comparing a load-displacement profile of riveting to a pre-set profile to determine whether the riveting was performed properly.

A press-in fastener has from top to bottom: a head, a clinch feature, and a spiral, knurled shank. The fastener can hold two parts together by first clinching with a first metal panel, and then being pressed into a hole in a second, non-ductile panel having a uniform interference between the knurled fastener shank and the hole. The knurled shank has a helix configuration that allows for use in non-ductile materials and eliminates the need for tapered holes and screws for applications that do not require disassembly.

A method of bonding a connector to a first object includes providing the connector, the connector being separate from the first object and including a thermoplastic material; arranging the first object and the connector relative to one another so that the connector reaches from a proximal side of the object through a first opening in the object; generating and applying vibrations and mechanical pressure to the connector until a flow portion of the thermoplastic material is liquefied and caused to flow sideways radially into an open space; and removing the source of the vibrations and causing the liquefied thermoplastic material to re-solidify, resulting in the connector with a foot portion, a head portion, and a shaft portion between the foot portion and the head portion. The shaft portion extends along an axis through the first opening, and secures the connector to the first object.

The method includes the step of positioning the sheets in an at least partially overlapping relationship. The method continues with the step of inserting a rivet that has a height through an overlapping area of the sheets. The method proceeds with the step of, with the rivet at a temperature in the range of 15-30 Celsius, collapsing the rivet between a pair of ramming surfaces to shorten the rivet and partially expand the rivet outwardly to lock the rivet with the sheets. The entire method results in a very strong connection between the sheets and with a great durability at a low cost.