Fabrication of magnesium alloy tubes for biodegradable stents by die-less mandrel drawing

Abstract

Mg alloy (ZM21) tubes were drawn using a die after die-less mandrel drawing, and dimensions and surface roughness were measured to fabricate the Mg alloy tubes for a bioabsorbable stent. As a result, the larger the speed ratio in die-less mandrel drawing, the greater the amount of wall thickness reduction from the original tubes. Furthermore, the die reduction where the outer surface roughness was minimum decreased as the speed ratio increased. Under above optimal conditions, Mg alloy tubes with an outer diameter of 3 mm and a wall thickness of 0.3 mm were fabricated.