A fastener for use in joining dissimilar materials manufactured by the process of producing the fastener with an external surface that forms an electrically insulating oxide layer when subjected to oxidation and, after manufacture and prior to use, subjecting the fastener to a pre-oxidation process to grow the desired oxide layer in situ on the external surface of the fastener. The present invention also provides a dissimilar material joint in which the pre-oxidized fastener is used to mechanically join dissimilar materials with the oxide layer electrically insulating the fastener from at least one of the dissimilar materials. The fastener may be a rivet used in friction self-piercing riveting (F-SPR). The fastener may be fabricated from an alloy capable of forming Al.sub.2O.sub.3 or Cr.sub.2O.sub.3 by thermal oxidation. The fastener may be pre-coated with Al or Cr that functions as a seed layer to form Al.sub.2O.sub.3 or Cr.sub.2O.sub.3.

Methods of fastening are provided. A method comprises contacting a fastener with a first layer of an assembly at a first location. The assembly comprises the first layer, a third layer, and a second layer positioned intermediate the first layer and the third layer. The first layer, the third layer, and the fastener are electrically conductive. The second layer defines a gap and the first location is in communication with the gap. Electrical communication is formed between the assembly and the fastener. The first layer is fastened to the third layer through the gap in the second layer with the fastener. The fastening comprises resistance welding the fastener to the third layer.

Methods of fastening are provided. A method comprises contacting a fastener with a first layer of an assembly at a first location. The assembly comprises the first layer, a third layer, and a second layer positioned intermediate the first layer and the third layer. The first layer, the third layer, and the fastener are electrically conductive. The second layer defines a gap and the first location is in communication with the gap. Electrical communication is formed between the assembly and the fastener. The first layer is fastened to the third layer through the gap in the second layer with the fastener. The fastening comprises resistance welding the fastener to the third layer.

A collet assembly including an actuator and a collet connected to the actuator. The collet assembly is adapted to be installed on a welding electrode holder having an electrode. The collet is moveable by the actuator from an advanced position, in which the collet is adapted to grip a fastener such as a welding rivet, and a retracted position, in which at least a portion of the collet is retracted into the actuator to enable the electrode to engage the fastener for welding to a work piece, and the collet is adapted to release the fastener.

The invention relates to a connecting element (10) having a hollow-cylindrical shaft (12) and a drive (16), via which the shaft (12) can be driven in a direction of rotation, wherein the hollow-cylindrical shaft (12) has at least one free end, wherein the drive (16) is arranged opposite the free end, wherein a hollow space is formed by the hollow-cylindrical shaft (12). The invention is characterized in that driver structures (22) acting in the circumferential direction of the hollow-cylindrical shaft (12) are arranged in the hollow space, which, projected on the lateral surface, are arranged to extend in the setting direction on the lateral surface, rectilinearly parallel to the element mid-axis (M) or with an angular deviation of at most 20° with respect to the element mid-axis (M), and/or are arranged at the end on the drive side.

A self-piercing rivet for joining workpieces comprises: a head defining a head diameter, and a shank which defining a shank diameter. The shank on a foot end opposite to the head, partially defines an axial recess which has an axial depth. The shank further includes a flat surface portion or a circular cutter on the foot end. And an axial circular recess is partially defined in a transition portion between the head and the shank.

A fastener delivery apparatus comprising a nose assembly configured to convey a fastener towards a workpiece, the nose assembly comprising a barrel and a fastener alignment device; wherein the barrel comprises a bore having a longitudinal axis and a distal end for engaging the workpiece; an actuator configured to urge the fastener through the bore; wherein the fastener alignment device comprises a plurality of resilient arms which extend towards the distal end of the barrel; wherein at least part of each of the plurality of resilient arms projects into the bore via apertures in the barrel; wherein the plurality of resilient arms are biased radially inwards to engage the fastener; and wherein the resilient arms are configured such that at a maximum deflection, the resilient arms do not pass beyond the periphery of the barrel.

Disclosed is a method for automatically determining quality of a self-piercing riveting process, including the following operations: inputting standard values, acquiring data in real-time, and comparing data and determining quality of riveting. Riveting parameters and process curves are obtained in real time by a data acquisition system, the measured values for determining quality of riveting is calculated according to the real-time change of the riveting force curve and information of the riveted plates, the quality of the riveting process can be automatically determined by comparing the measured values and the standard values, the efficiency of monitoring quality is improved, inspection of all riveting points can be realized, abandonment of white vehicle bodies due to poor riveting quality is greatly reduced, and the problem that a large number of white vehicle bodies with defective quality cannot be found is avoided, and the riveting quality of the white vehicle bodies is guaranteed.

A method for manufacturing a joined body includes at least one first plate material, one second plate material, and a self-piercing rivet where a cylinder portion projects from a head. The method includes: a test step of plastically deforming the second plate material by a load in a plate thickness direction to measure physical value information of the second plate material; a setting step of setting a joining condition based on the physical value information by the test step; and a joining step of supporting a back surface of the second plate material having a front surface on which the first plate material is stacked with a die and driving the cylinder portion from the front surface side toward a concave portion provided in the die to join the first plate material and the second plate material together based on the joining condition set by the setting step.

A joining device comprises a die and driving means. A first concave portion is recessed in a substantially cylindrical shape in a driving direction on the die, and a second concave portion is recessed in the driving direction in a central portion on a bottom face of the first concave portion. A portion on an external side of the second concave portion on the bottom face of the first concave portion forms a terrace portion that is shallower than the second concave portion, and a diameter of the foot portion of the self-piercing rivet corresponds to a diameter of the terrace portion. In driving the foot portion of the self-piercing rivet toward the terrace portion of the first concave portion, the foot portion of the self-piercing rivet is spread outward by the terrace portion and a part of the members to be joined runs into the second concave portion.