Mechanisms for improving the stiffness transition across a dissimilar metal weld joint

Abstract

The present disclosure is directed to multi-segment intraluminal guide wires including an elongate distal portion comprising a first metallic material (e.g., nitinol), an elongate proximal portion comprising a second metallic material (e.g., stainless steel). The distal and proximal portions may be directly joined together end to end by a solid-state weld joint. A diameter of the weld region surrounding the weld joint on either side of the weld joint may be reduced (e.g., ground down) relative to the diameter of the distal and proximal portions of the guide wire on either side of the weld region. A stiffness adjusting sleeve may be disposed over the weld joint so that a transition profile of bending stiffness across the weld region is gradual, rather than abrupt across the distal portion of the guide wire to the proximal portion of the guide wire. A polymer jacket may cover the sleeve and distal portion.