Precessing rivet and method for friction stir riveting

摘要

A friction stir rivet is rotated in a precessing motion and driven through a first fusible workpiece into an engaged second fusible workpiece, causing local portions of the first and second workpieces to plasticize. When the rivet is driven through the first workpiece and into the second workpiece, rotation is stopped and the plasticized material solidifies around the rivet creating an enlarged weld joining the metal workpiece and encompassing the rivet, which provides additional mechanical strength.