Abstract: A screw includes a head portion, an externally threaded shank extending from the head portion, the externally threaded shank having an external surface, and a flow-hole-forming tip disposed at a distal end portion of the externally threaded shank. The flow-hole-forming tip includes a convex radiused lower zone having an external surface, a concave radiused middle zone having an external surface tangent to the external surface of the convex radiused lower zone, and a radiused distal end zone having an external surface tangent to the external surface of the concave radiused middle zone.

Abstract: A screw includes a head portion, an externally threaded shank extending from the head portion, the externally threaded shank having an external surface, and a flow-hole-forming tip disposed at a distal end portion of the externally threaded shank. The flow-hole-forming tip includes a radiused lower zone having an external surface tangent to the external surface of the externally threaded shank, a conical middle zone having an external surface tangent to the external surface of the radiused lower zone, the conical middle zone defining a vertex angle, and a radiused distal end zone having an external surface tangent to the external surface of the conical middle zone. The flow-hole-forming tip includes a width of the flow-hole-forming tip is greater than a length of the flow-hole-forming tip and/or the vertex angle is greater than or equal to 90 degrees.

Abstract: A fastener including an elongated shaft extending between first and second shaft ends, with a tip provided at the first shaft end, and a thread region provided between the tip and the second shaft end; and a head with a drive region arranged at the second shaft end. The fastener also incudes a first annular undercut area in an underside surface of the head, where the first annular undercut area is configured and arranged to receive material that has flowed from a substrate during installation of the fastener into the substrate, and a second annular undercut area in the underside surface of the head, where the second annular undercut area is located radially outwardly of the first annular undercut area. Additionally, an annular sealing member is provided within the second annular undercut area, where the annular sealing member makes sealing contact with an upper surface of the substrate.

Abstract: A self-penetrating thread forming and flow drilling fastener for thick materials with a generally cylindrical partially threaded shank, a drive system at the first end of the shank and a flow drilling tip at the second end of the shank. The flow drilling tip is sized larger than the minor diameter of the threaded shank but less than the major diameter to control installation torque enabling installation into thick materials with greatly reduced risk of torsional failure resultant from a decrease in torque. The flow drilling tip and threads may be a variety of shapes or thread types based on the substrate material the fastener is installed into.

Abstract: A fastener has a generally cylindrical shank and a driver at a first end of the shank. The shank has a thread having a first side and a second side opposed to the first side. The first and second sides form a compound angle between the shank and an apex where the first and second sides meet. The compound angle is formed by a body portion extending along the first and second sides from the shank to an intersection, and a crest portion extending along the first and second sides from the intersection to the apex. The first and second sides in the body portion form a body angle with respect to each other, and the first and second sides in the crest portion form a crest angle with respect to each other. The crest angle is greater than the body angle.

Abstract: A fastener has a generally cylindrical shank and a driver at a first end of the shank. The shank has a thread having a first side and a second side opposed to the first side. The first and second sides form a compound angle between the shank and an apex where the first and second sides meet. The compound angle is formed by a body portion extending along the first and second sides from the shank to an intersection, and a crest portion extending along the first and second sides from the intersection to the apex. The first and second sides in the body portion form a body angle with respect to each other, and the first and second sides in the crest portion form a crest angle with respect to each other. The crest angle is greater than the body angle.

Abstract: Electrically assisted flow drill screwdriving processes (EAFDS) and devices are described. The methods can augment traditional FDS and allow for softening of metals of a stack-up, which can enable FDS joining of thicker and stronger materials such as boron steel. EAFDS methods can reduce cycle time and can be used to join thicker cross-sections with reduced installation torque. Also disclosed are fixtures for attachment to existing devices that can provide for the electrical augmentation of existing FDS processes.

Abstract: Electrically assisted flow drill screwdriving processes (EAFDS) and devices are described. The methods can augment traditional FDS and allow for softening of metals of a stack-up, which can enable FDS joining of thicker and stronger materials such as boron steel. EAFDS methods can reduce cycle time and can be used to join thicker cross-sections with reduced installation torque. Also disclosed are fixtures for attachment to existing devices that can provide for the electrical augmentation of existing FDS processes.