A method of joining a multiple member work-piece includes providing a first steel work-piece having a first thickness and a second steel work-piece having a second thickness. The first thickness is at least twice the second thickness. A third material is disposed in contact with the second steel work-piece. For example, the third material may be in the form of a rivet, a plurality of pins, or a coating material. The method includes resistance welding the first and second work-pieces together. A bonded assembly includes the first and second steel members and the third material being bonded together, where the thickness of the first member is at least twice the thickness of the second member.

A method of fitting a fastener to an object is introduced. The fastener has a weldable surface and an engaging portion or a hole portion. One end of the hole portion or one end of the engaging portion has a holding portion. During a welding heating process, solder flows into or enters the holding portion and then cools down and solidifies therein so as to be held therein. Therefore, the weldable surface and the holding portion together enable the fastener to be firmly coupled to an object. The engaging portion and the hole portion together enable an object to be coupled to or removed from another object, so as to couple together and separate at least two objects repeatedly and quickly.

A method of anchoring a connector element (10) in a receiving object (66) comprises inserting a distal end of the connector element (10) into a mounting hole in an insertion direction along an insertion axis; inserting a sleeve (36) comprising a thermoplastic material into the mounting hole, the sleeve (36) enclosing the connector element (10); and transferring energy to liquefy at least a portion of the thermoplastic material of the sleeve (36). A machine (500) configured for carrying out the method and a connector element anchoring kit comprising a connector element (10) and a sleeve (36) comprising thermoplastic material.

Presented are protective covers for weldable fasteners, methods for making/using such cover-protected weldable fasteners, and motor vehicles with such covered fasteners welded to load-bearing structural members. A weldable fastener assembly includes a fastener, such as a weld-on nut or clip retainer, that is fabricated with a shank and a flange. One end of the shank has a fastener hole that receives therethrough a mating fastener, such as a bolt, screw, stud, or clip. The flange is formed, in whole or in part, from a weldable material for welding to a load-bearing panel or other structural support member. The flange may be integrally formed with and project radially outward from the shank. A protective cover is attached to the flange and covers the fastener hole. The protective cover is frangible and formed, in whole or in part, from a material designed to withstand the temperature at which the weldable material melts.

A welding element is operable for being connected to a workpiece using a welding method. The welding element comprises: a head and a shaft like anchor portion. The head includes a welding surface, a stop surface that is remote from the welding surface, and a plurality of pointed projections evenly and uniformly distributed over the entire welding surface. The shaft-like anchor portion extends along a longitudinal axis between a first end region and a second end region, with the first end region connected to the stop surface.

A bolt is provided for fastening a component or a ground connection of electrical or electronic components to a vehicle body. The bolt has a head portion with an external thread, the head portion being formed from a steel material, and a foot portion. The foot portion is formed from an aluminum alloy and is connected integrally to the head portion by a friction-weld connection. The bolt is configured in the form of a welding stud for drawn arc stud welding, for which purpose it has an ignition tip on its end side, which delimits the foot portion.

A structure for fastening vehicle components with adjustable steps includes a weld nut configured to be fixed to a vehicle floor panel, an inner bolt positioned above and fixedly inserted into the weld nut, and an assembly bolt inserted through the inner bolt and fastened to one end of the weld nut, wherein the inner bolt is configured to move in a height direction for step adjustment.

A method of anchoring a connector element (10) in a receiving object (66) comprises inserting a distal end of the connector element (10) into a mounting hole in an insertion direction along an insertion axis; inserting a sleeve (36) comprising a thermoplastic material into the mounting hole, the sleeve (36) enclosing the connector element (10); and transferring energy to liquefy at least a portion of the thermoplastic material of the sleeve (36). A machine (500) configured for carrying out the method and a connector element anchoring kit comprising a connector element (10) and a sleeve (36) comprising thermoplastic material.

The dissimilar material joint structure 1 includes a plate member 20, a weld nut 10 on a front surface of the plate member, and a washer 30 on a back surface of the plate member. The weld nut and the plate member are made of dissimilar materials different from each other. The weld nut includes a projection 12 on a bearing surface thereof. The plate member has a bolt through-hole 23 located on a center axis of the weld nut, for passing therethrough a bolt 40 corresponding to the weld nut and a projection through-hole 24 on the periphery of the bolt through-hole. The projection through-hole is penetrable by the projection. The weld nut is not directly welded to the plate member but joined to the plate member by being welded to the washer via the projection penetrating the projection through-hole.

A fastener has a head and a shank coupled to the head and extending along a central axis of the fastener. A plurality of engagement members are disposed on a peripheral surface of the shank and connected to the shank at a point of connection to project away from the shank. The plurality of engagement members can collectively act as external threads and are flexible with respect to the shank to be relatively moveable with respect to the shank.