HYPOTUBE WITH ENHANCED STRENGTH AND DUCTILITY

摘要

Hypotubes for use with intra-corporal medical devices are fabricated from a stainless steel alloy exhibiting a combination of excellent yield strength with improved ductility as compared to cold worked AISI 304 stainless steel, from which hypotubes are typically fabricated. The stainless steel alloy may have: (1) a nitrogen content, a carbon content, or a combined nitrogen and carbon content that is greater than that allowed in AISI 304 stainless steel, providing an increased concentration of interstitial atoms to stabilize dislocations generated by cold work and/or (2) a combined nickel and manganese content that is lower than that allowed in AISI 304 stainless steel to reduce the stability of the austenitic structure, enabling a greater percentage of martensite to be stress-induced by a given level of cold work as compared to AISI 304 SS. Following cold working, the alloy may be heat treated to raise its yield strength by strain aging.

主权项

1. A hypotube for use with an intra-corporal medical device, the hypotube comprising:
an elongate hollow body extending from a proximal end to a distal end; at least a portion of the elongate hollow body being fabricated from a stainless steel alloy having: (1) a nitrogen content, a carbon content, or a combined nitrogen and carbon content that is greater than an upper specification limit for AISI 304 stainless steel and/or (2) an austenitic stabilizer content that is lower than a lower specification limit for AISI 304 stainless steel.