Austenitic nitinol medical devices
First Claim
1. A medical device for use in a mammalian body, comprising:
- a structurally expandable intraluminal element, wherein the intraluminal element includes a binary superelastic alloy; and
the superelastic alloy includes a martensitic phase and an austenitic phase, with a transformation temperature set below a mammalian body temperature such that the superelastic alloy of the intraluminal element is always in the austenitic phase with no stress-induced martensite while under applied stress within the mammalian body.
2 Assignments
0 Petitions
Accused Products
Abstract
A medical device for use within a body lumen that is made from a binary nickel-titanium alloy that remains in its austenitic phase throughout its operational range is disclosed. The medical device, such as an intraluminal stent, is made from superelastic nickel-titanium and may optionally be alloyed with a ternary element. By adding the ternary element and/or through heat treatment, it is possible to lower the phase transformation temperature between the austenitic phase and the martensitic phase of the nickel-titanium alloy. By lowering the phase transformation temperature, the martensite deformation temperature is likewise depressed. It is possible then to depress the martensite deformation temperature below body temperature such that when the device is used in a body lumen for medical treatment, the nickel-titanium device remains completely in the austenitic phase without appearance of stress-induced martensite even if the device is placed under stress.
-
Citations
20 Claims
-
1. A medical device for use in a mammalian body, comprising:
-
a structurally expandable intraluminal element, wherein the intraluminal element includes a binary superelastic alloy; and
the superelastic alloy includes a martensitic phase and an austenitic phase, with a transformation temperature set below a mammalian body temperature such that the superelastic alloy of the intraluminal element is always in the austenitic phase with no stress-induced martensite while under applied stress within the mammalian body. - View Dependent Claims (2, 3, 4, 5, 6, 7)
-
-
8. A medical device for use in a lumen of a human body, comprising:
-
an intraluminal element, wherein the element includes a binary superelastic alloy; and
the superelastic alloy having a martensitic phase and an austenitic phase, wherein a martensite deformation temperature (Md) of the alloy is depressed to below human body temperature. - View Dependent Claims (9, 10, 11, 12, 13)
-
-
14. A method for providing a medical device for use in a lumen of a human body, comprising:
-
providing an intraluminal element having a binary superelastic alloy, wherein the superelastic alloy includes a martensitic phase and an austenitic phase; and
depressing a martensite deformation temperature (Md) of the alloy to below human body temperature. - View Dependent Claims (15, 16, 17, 18, 19, 20)
-
Specification