Optimization Technology and Developing of Vascular Stents

Abstract:

Stents have been used for the treatment of cardiovascular diseases and are often placed inside coronary arteries. The manufacture of metal stents is a challenging issue because of the features, like geometry and the material of stents. An improved manufacturing process of stents is presented. The proposed processes consist of the following steps: boring and polishing, laser cutting, vacuum annealing and surface finishing (ultrasonic cleaning, acid pickling, and electrolytic polishing). The precision boring operation is used to obtain the required wall thickness from off-the-shelf seamless tube. The laser cutting is performed to change the shape of the stent, and the finishing operations is selected to modify the surface features, like smoothness and texture of stents. 316LVM stainless steel sample with an outside-diameter of 3 mm, a wall thickness of 0.1 mm, and a length of 25 mm, had been manufactured and demonstrated the proposed manufacture technology. The surface roughness of a stent manufactured is the value of Ra 14.3 nm which basically meets the design requirement for further performance evaluation. It is hoped that the above finding can be used for future study of stents.

• Periodical: Applied Mechanics and Materials (Volumes 284-287)
• Pages: 390-397
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.284-287.390
• Online since: January 2013
• Authors: Cheng Shun Chen, Sheng Yao Lin, Nai Kuan Chou
• Keywords: Laser Cutting, Stent, Surface Finishing, Vacuum Annealing

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