Faculty of Chemical and Materials Engineering, University of the Punjab, Lahore
Abstract
This paper proposes a helical type stent made by using Shape Memory Alloy (SMA) material known as Nitinol. The stent is produced by laser cutting technique, having helical shaped zigzag loops in order to behave like an inductor. A capacitor is integrated on inductive stent to build an L-C tank circuit. This L-C resonant stent act as a wireless heater operated under Radio-Frequency (RF) magnetic field applied externally. The stent is fabricated by using 6 mm diameter Nitinol tubes with wall thickness of 0.1 mm having austenite finish (Af) temperature equals to 60°C. The helical stent is heated by applying potential difference across its ends and the results obtained from experiment were compared with the simulation results. It is concluded that the stent require 2.5 V or 1.5 Watts of energy to reach the temperature of 50° C which is an ideal temperature for hyperthermia treatment. The fabricated stent is electromechanically coupled with different types of capacitors in order to characterize its electrical properties and resonance frequency. The inductance of stent is found to be between 350 µH – 400 µH. At the end, mechanical properties of stent are also characterized and compared with commercial stent to ensure its practical validity
