Patent ID: 6676007
Filing Date: 2004-01-13
Classification: B21J,B23K

Abstract:
A method of attaching metal members for forming an automotive vehicle structure, comprising the steps of:(a) providing a first metal member; (b) contacting the first metal member with a second metal member; (c) providing a metal fastener that is substantially symmetrical about a central axis, the metal fastener including a top radially enlarged portion, a bottom radially enlarged portion and a shank portion intermediate the thicker portions for forming a circumferential groove about the axis and fastener; (d) rotating the metal fastener about the axis using a rotary driving apparatus; and (e) driving the metal fastener through the first member and into the second member during rotation of the fastener thereby inducing friction between the fastener, the first member and the second member for at least locally melting portions of the first member and the second member to form a flowable material that flows into the circumferential groove of the fastener and wherein the fastener is driven only partially into the second member; and (f) solidifying the flowable material within the circumferential groove for integrally attaching the flowable material, the fastener, the first member and the second member together wherein the flowable material metallurgically bonds with at least the first member and the second member.