OPTIMAL DESIGN OF AUXETIC, ADDITIVELY MANUFACTURED, POLYMERIC STRUCTURES

This work is concerned with the optimal design, additive manufacturing, and testing of microarchitectured polymer materials with desired macroscopic mechanichal properties. More precise, we are interested in designing and fabricating a materials microstrure in terms of the topology as well as material distribution of the individual phases within a periodic unit cell. In the design process we use the level set method to identify material regions and track boundary changes within the context of the smoothed interface. The combination of the level set method and the shape derivative obtained in the smoothed interface context allows us to capture, within the unit cell, the topological changes that take place. The obtained unit cells are smoothed and enhanced using standard image processing techniques and have periodically been multiplied into rectangular specimens. The specimens are manufactured using a commercial steoreolithography Ember printer and mechanically tested. The observed fields are compared with predictions from the simulations