MECHANISMS FOR IMPROVING THE STIFFNESS TRANSITION ACROSS A DISSIMILAR METAL WELD JOINT

摘要

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.

主权项

1. A multi-segment intraluminal guide wire comprising:
an elongate first distal portion comprising a first metallic material; an elongate second proximal portion comprising a second metallic material that is different from the first metallic material, the distal and proximal elongate portions being joined together end to end by a solid-state weld joint; a diameter of a weld region surrounding the weld joint being reduced relative to a diameter of the distal and proximal portions of the guide wire on either side of the weld region; a stiffness adjusting sleeve 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, wherein the stiffness adjusting sleeve is:
formed from a multifilar coil including multiple strands of helically wound wire disposed over the weld region 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; orthe stiffness adjusting sleeve including a sleeve body in which at least one end thereof is tapered in thickness 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.