Optimization of Laser Processing in the Fabrication of Stents

Abstract

Stents are commonly inserted into coronary arteries for treating cardiovascular diseases. Nonetheless, the process of manufacturing metal stents is challenging owing to the geometric design, the optimization of machining methods and the materials involved. Fiber lasers were used as the laser cutting technology for cutting stents. The experiment revealed the importance of precise technical parameters, including the lens’ focal length, focus position, pulse frequency, cutting speed and pulse width. These parameters strongly influence the kerfs width and the quality of the cutting seam surface. Our results indicate that the width of the kerfs increases with an increase in the pulse frequency and pulse width, whereas it decreases or shows minimal change at higher cutting speeds. The surface roughness for stent laser cutting was Ra 43.5 nm, which essentially meets the design requirement for further performance evaluation. Finally, high-quality cutting of a 316LVM stainless steel vascular stent was achieved.