Permanent Implantable Metal Materials
Stainless Steel: The earliest material used for stents; it offers good radial strength but has thicker struts, so it is rarely used in clinical practice today.
Cobalt-Chromium/Platinum-Chromium Alloys: Currently the mainstream clinical materials; they are thinner and more biocompatible, reduce the risk of post-procedural restenosis, and offer superior MRI compatibility.
Nitinol (Nickel-Titanium Alloy): Possesses shape-memory properties, allowing it to expand automatically at body temperature; commonly used for self-expanding stents in peripheral vessels and carotid arteries.
Other materials include special alloys such as tantalum, which offer excellent flexibility and corrosion resistance, making them suitable for complex vascular anatomies.
Absorbable/Degradable Materials
Polylactic Acid (PLA) Polymers: The mainstream material for absorbable stents; they gradually break down into water and carbon dioxide within 2–3 years of implantation, leaving no foreign material in the body.
Magnesium Alloys/Iron Alloys: Degradable metal materials that offer better radial strength than polymers; these are currently still undergoing clinical optimization.