Radiopaque enhanced cobalt alloy for stents

Patent metadata

Field	Value
Publication number	US-11141296-B2
Application number	US-201715421632-A
Country	US
Kind code	B2
Filing date	Feb 1, 2017
Priority date	Apr 26, 2012
Publication date	Oct 12, 2021
Grant date	Oct 12, 2021

Abstract

A stent is formed of at least a cobalt-based alloy. The cobalt-based alloy may include 10-35 weight % metal member selected from the group consisting of platinum (Pt), gold (Au), iridium (Ir), osmium (Os), rhenium (Re), tungsten (W), palladium (Pd), tantalum (Ta), and combinations thereof; 16-21 weight % chromium (Cr); 9-12 weight % molybdenum (Mo); 0-25 weight % nickel (Ni); and balance cobalt (Co). The cobalt-based alloy may be a thin outer shell of a hollow stent. The cobalt-based alloy may be used to form at least one of an inner core and an outer shell of a core-shell structure of a stent. The cobalt-based alloy may be used to form an end of a wire for forming a stent.

First claim

What is claimed is:

1. A stent comprising:
a cobalt-based alloy, wherein the cobalt-based alloy is free of molybdenum (Mo), the cobalt based alloy comprising
about 14 weight % tungsten (W) and 10-14 weight % platinum (Pt);
20-24 weight % chromium (Cr);
8-12 weight % nickel (Ni);
0-3 weight % iron (Fe); and
balance cobalt (Co).

2. The stent of claim 1 , wherein the cobalt-based alloy is free of molybdenum (Mo) and is formed of:
about 14 weight % tungsten (W) and 10-14 weight % platinum (Pt);
about 22 weight % chromium (Cr);
8-12 weight % nickel (Ni)
0-0.15 weight % carbon (C);
0-3 weight % iron (Fe);
about 1.5 weight % manganese (Mn);
0-1.0 weight % silicon (Si);
0-0.03 weight % lanthanum (La); and
balance cobalt (Co).

3. A stent comprising:
a plurality of struts formed by a wire, the wire comprising an outer shell substantially surrounding an inner core, wherein one of the outer shell and the inner core comprises a cobalt-based alloy and the other of the outer shell and the inner core comprises a metal member selected from the group consisting of platinum (Pt), gold (Au), iridium (Ir), osmium (Os), rhenium (Re), tungsten (W), palladium (Pd), tantalum (Ta), and combinations thereof, the cobalt-based alloy comprising:
10-35 weight % the metal member;
16-21 weight % chromium (Cr);
9-12 weight % molybdenum (Mo);
10-18 weight % nickel (Ni);
0-3 weight % iron (Fe); and
balance cobalt (Co).

4. The stent of claim 3 , wherein the metal member of the cobalt-based alloy and the metal member of the other of the outer shall and the inner core comprises about 20% to and 45% by weight of the total wire comprising the outer shell and the inner core.

5. The stent of claim 3 , wherein the cobalt-chromium alloy comprises about 1 weight % iron (Fe).

6. A stent comprising:
a cobalt-based alloy comprising
10-35 weight % metal member selected from the group consisting of platinum (Pt), gold (Au), iridium (Ir), osmium (Os), rhenium (Re), tungsten (W), palladium (Pd), tantalum (Ta), and combinations thereof;
16-21 weight % chromium (Cr);
9-12 weight % molybdenum (Mo);
10-18 weight % nickel (Ni);
0-3 weight % iron (Fe); and
balance cobalt (Co).

7. The stent of claim 6 , wherein the cobalt-chromium alloy comprises about 1 weight % iron (Fe).

8. The stent of claim 6 , wherein the cobalt-based alloy further comprises one or more of
0-0.015 weight % boron (B);
0-0.15 weight % carbon (C);
0-1.5 weight % manganese (Mn);
0-0.04 weight % phosphorous (P);
0-1.0 weight % silicon (Si);
0-1 weight % titanium (Ti); and
0-0.03 weight % sulfur (S).

9. The stent of claim 6 , wherein the cobalt-based alloy further comprises one or more of
about 0.010 weight % boron (B);
0-0.025 weight % carbon (C);
0-1.0 weight % iron (Fe);
0-0.15 weight % manganese (Mn);
0-0.015 weight % phosphorous (P);
0-0.15 weight % silicon (Si);
0-0.01 weight % sulfur (S); and
0-1 weight % titanium (Ti).

Assignees

• Medtronic Vascular Inc

Inventors

• Thompson Dustin

Classifications

• A61L31/022 Primary

  Metals or alloys · CPC title

• A61L31/18

  Materials at least partially X-ray or laser opaque · CPC title

• C22C19/07

  based on cobalt · CPC title

• A61F2250/0098

  radio-opaque, e.g. radio-opaque markers · CPC title

• A61F2002/91558

  connected peak to peak · CPC title