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Material : Tantalum stent made of tantalum wires
Temper : annealed
Specs : according to ASTM F 560 -98 R05400 or ISO 5832-3
Chemical composition :
O 0.0300 %max
C 0.0100 %max
N 0.0100 %max
H 0.0015 %max
Fe 0.0100 %max
Ni 0.0100 %max
Si 0.0050 %max
Mo 0.0200 %max
W 0.0500 %max
Nb 0.1000 %max
Ta balance (typically 99.95%)
Physical & Mechanical property :
Tensile strength 172 MPa min.
Yield strength 103 MPa min.
Elongation 25%min
Dimensions :
0.15mm up to 0.50mm diameter
Straight tantalum wire can be fabricated into Tantalum stent, straight tantalum wire i s formed into a wave pattern. Wrapping of the formed wire to line up U points, which are then welded. Finished device is tantalum expanded mesh, similar to polyetherurethane-coated tantalum wire stents used in the experiment.
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Radiopaque tantalum for medical devices:
A radiopaque tantalum medical device such as a stent for use with or implantation in a body lumen is disclosed. The stent is made from a superelastic alloy such as tantalum, nickel-titanium or nitinol,
and includes a ternary element selected from the group of chemical elements consisting of iridium, platinum, gold, rhenium, tungsten, palladium, rhodium, tantalum, silver, ruthenium, or hafnium. The added ternary element improves the radiopacity of the tantalum stent comparable to that of a stainless steel stent of the same size and strut pattern coated with a thin layer of gold. The tantalum stent has improved radiopacity yet retains its superelastic and shape memory behavior and further maintains a thin strut/wall thickness for high flexibility.
