Fatigue damage resistant wire and method of production thereof

Abstract

A guide wire made from a cobalt-nickel-chromium-molybdenum alloy is provided. The wire provides, for example, a combination of relatively high yield strength and ductility to increase the ability of the guide wire to withstand both pre-procedural, physician-planned plastic deformation and subsequent procedural elastic deformation en route to a target lesion.

1 - 24 . (canceled) 
     
     
         25 . A medical guide wire device, comprising:
 an elongate metallic wire made at least in part of a cobalt-nickel-chromium-molybdenum alloy having no greater than 0.7 weight percent titanium.   
     
     
         26 . The guide wire device of  claim 25 , wherein said alloy includes less than 30 ppm nitrogen. 
     
     
         27 . The guide wire device of  claim 25 , wherein said alloy includes less than 20 ppm nitrogen. 
     
     
         28 . The guide wire device of  claim 25 , wherein said alloy includes less than 0.03 weight percent titanium. 
     
     
         29 . The guide wire device of  claim 25 , wherein said alloy comprises:
 at least 20 weight percent cobalt;   32.7 to 37.3 weight percent nickel;   18.75 to 21.25 weight percent chromium; and   8.85 to 10.65 weight percent molybdenum.   
     
     
         30 . The guide wire device of  claim 29 , wherein said alloy comprises:
 33.0 to 37.0 weight percent nickel;   19.0 to 21.0 weight percent chromium; and   9.0 to 10.5 weight percent molybdenum.   
     
     
         31 . The guide wire device of  claim 25 , wherein said alloy further comprises at least one of at least 0.05 to 0.15 weight percent aluminum, at least 5 to 20 ppm calcium, at least 5 to 50 ppm magnesium, and at least 5 to 50 ppm cerium. 
     
     
         32 . The guide wire device of  claim 25 , said alloy consisting of:
 at least 20 weight percent cobalt;   32.7 to 37.3 weight percent nickel;   18.75 to 21.25 weight percent chromium;   8.85 to 10.65 weight percent molybdenum;   less than 30 ppm nitrogen;   less than 0.7 weight percent titanium;   at least one of at least 0.05 to 0.15 weight percent aluminum, at least 5 to 20 ppm calcium, at least 5 to 50 ppm magnesium, and at least 5 to 50 ppm cerium;   no greater than 1.05 weight percent iron;   no greater than 0.035 weight percent carbon;   no greater than 0.18 weight percent manganese;   no greater than 0.17 weight percent silicon;   no greater than 0.020 weight percent phosphorus;   no greater than 0.015 weight percent sulfur;   no greater than 0.020 weight percent boron; and   incidental impurities.   
     
     
         33 . The wire of  claim 25 , wherein said wire defines a drawn wire construct. 
     
     
         34 . The wire of  claim 33 , wherein said drawn wire construct comprises substantially equiaxed grains. 
     
     
         35 . The guide wire device of  claim 25 , wherein said guide wire defines a ratio of yield strength to ultimate strength between 0.85 and 0.97. 
     
     
         36 . The guide wire device of  claim 25 , wherein said guide wire defines one of a diameter and a thickness, said guide wire having an axial ductility of between 6% and 17.9% strain to rupture, as measured by a monotonic tensile test with a gauge length exceeding 250× said thickness of the wire at a temperature of 298±5K. 
     
     
         37 . The wire of  claim 36 , said wire having a yield strength of at least 1393 MPa and as much as 1646 MPa. 
     
     
         38 . The wire of  claim 25 , said wire having a yield strength of at least 1393 MPa and as much as 1646 MPa. 
     
     
         39 . The wire of  claim 25 , said wire having an elastic modulus of at least 21.8 Mpsi and as much as 24.5 Mpsi. 
     
     
         40 . The guide wire device of  claim 25 , wherein said metallic wire defines:
 one of a thickness and a diameter equal to less than 1.0 mm, and   a mean grain size of less than 500 nanometers throughout said non-shape memory metal or metal alloy of said metallic wire, as measured along all arbitrarily defined axes of the respective grains.   
     
     
         41 . The wire of  claim 25 , wherein said mean grain size is between 100 nanometers and 300 nanometers. 
     
     
         42 . The guide wire device of  claim 25 , wherein said elongate metallic wire includes a tapered end. 
     
     
         43 . The guide wire device of  claim 25 , wherein said elongate metallic wire is received within a coil wire. 
     
     
         44 . The guide wire device of  claim 25 , wherein said coil wire is received within a housing. 
     
     
         45 . The wire of  claim 25 , wherein said wire defines a diameter less than 0.5 mm. 
     
     
         46 . The wire of  claim 45 , wherein said wire defines a diameter of at least 0.127 mm.