Thermochemically treated miniature tubes as semifinished products for vascular stents

A method for increasing the fatigue strength of a tubular semifinished product for a medical implant, the method comprising the following steps:

• a) providing a tubular semifinished product comprising a continuous solid wall;
• b) applying pressure internally to the tubular semifinished product at room temperature to plastically deform the tubular semifinished product such that an inner diameter of the tubular semifinished product is increased from 0.5% to 1.5%;
• and
• c) forming a stent or a cardiac valve from the plastically deformed semifinished product.