Medical stents are metal tubes that are inserted into arteries, blood vessels and other passages in order to prevent or counteract the constricted flow of fluids.
Commonly used during angioplasty 
procedures to strengthen the coronary artery, stents must be strong enough to hold the artery's shape and flexible enough to be inserted within the vascular system without causing damage.
First developed in France during the 1980s, initial stents were made using 316L stainless steel, which contains up to 3 percent molybdenum.
Nowadays, a number of molybdenum-containing alloys are used to form different stents (see table below). That is because molybdenum's properties are mirror the primary qualities required of stents, including:
1. Bio-compatibility
2. Strength
3. Corrosion resistance
4. Low production cost
For more on molybdenum's role in medical stent's see: Molyreview. International Molybdenum Association. July 2012
Molybdenum-Containing Stent Alloys: Chemical Composition (wt. %)
| Common Name | UNS Number | ASTM | Chromium | Nickel | Cobalt | Platinum | Molybdenum | Iron |
| T316L | S31603 | F138 | 18 | 14 | - | - | 2.5 | 65 |
| T316 LVM | S31673 | F138 | 18 | 14 | - | - | 2.9 | 64 |
| Elgiloy®/Phynox® | R30003 | F1058 | 20 | 15 | 40 | - | 7 | 16 |
| MP35N® | R30035 | F562 | 20 | 35 | 34 | - | 9.8 | 1 |
| Pt-Cr Alloy | 18 | 9 | - | 33 | 3 | 37 |
Image: Frank C. Müller. File is licensed under the Creative Commons Attribution-Share Alike 2.5 Generic license.
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