Custom Elasticity Materials Through Mixing Thermoplastics with Extrusion 3D Printers

Abstract

Additive Manufacturing technology (AM) – or 3D printing – based on extrusion has experienced an undeniable boom due to the expiration of key patents. Nowadays many different companies are selling extrusion AM devices at very competitive prices bringing the advantages of AM closer to plain users, universities and companies dedicated to design or engineering. Parallel to the increase in the supply of these low-cost devices, the variety of materials available for 3D printing has become larger as well. However, the current availability of materials with an elasticity that lies between a rigid thermoplastic and a regular elastomer remains very limited. This paper aims to study how to produce custom elasticity materials by taking advantage of low-cost 3D printers capable of extruding the mix of two materials. Different materials will be created by combining a regular thermoplastic (PLA) with a Thermoplastic Polyurethane (TPU) that later will be mechanically characterized by means of tensile tests. The layer height was also introduced as a variable in the process. Results from this study show that a customized elastic modulus can be achieved for the printed part, and thus potential users can have the resources to cover their needs with regard to the choice of a mate-rial with certain properties.