Multiobjective Optimization of Laser Milling Parameters of Microcavities for the Manufacturing of DES

Abstract

A multiobjective optimization of the laser milling process of microcavities for the manufacturing of drug eluting stents (DES) is presented. The diameter, depth, and volume error are considered to be optimized in function of the process parameters (scanning speed, laser intensity, and pulse frequency). Several experiments are carried out following a design of experiments in a nanosecond pulsed Nd:YAG laser machine on 316 L Stainless Steel as a work material. Two different geometries are studied, and they are considered as another variable for the model. The multiobjective optimization problem is solved by NSGA-II algorithm, and the nondominated Pareto-optimal fronts are obtained. The capability of the process to manufacture within a level of error is also investigated. Relative error capability maps for different scale of features are presented