An apparatus and method for fastening dissimilar metals like steel and aluminum utilizes a steel rivet and a spot welding machine. The rivet and metals are stacked and the heat from the welder's electric current softens the lower melting point aluminum allowing the rivet to penetrate the aluminum and weld to the steel layer. The fastener may be used to join stacks with several layers of different materials and may be used to apply a threaded socket or stud made from steel or titanium to an aluminum or magnesium alloy structure. Layers of non-conductive materials like plastic and ceramics may also be affixed to a conductive layer using the fastener made from a compatible material that extends through a pilot hole.