Tenacidad a la fractura del ácido poliláctico (PLA) impreso en 3D antes y después de ser expuesto a un ambiente de degradación salino : evaluación de la tenacidad a la fractura de probetas de ácido poliláctico (PLA) preparadas con dos condiciones de impresión 3d y sin exposición a un ambiente de degradación salino.

Abstract

This work evaluated the fracture toughness of 3D printed polylactic acid (PLA), without exposure to a degradation environment. In this way, two appropriate 3D printing conditions for the manufacture of fracture toughness specimens were defined. The afore mentioned conditions comprise: two infill densities (60 y 80 %) and two infill patterns (concentric and gyroid), which were selected based on the literature. Other printing patterns like the print nozzle temperatures, printing speed, adhesion condition to the printing base, were established as parameters. Subsequently, fracture toughness specimens were manufactured, type SEN B (Single Edge notch bending), with the size and geometry described in the ASTM D5045-14 standard. Since these specimens have a notch where a pre-crack must be introduced, a literature review was carried out that allowed defining the method for fulfillment this requirement. Finally, the specimens were tested based on the previously indicated standard, in fracture mode I, thus establishing the effect of two 3D printing conditions on the fracture toughness of the prepared specimens. From the results obtained in this work, the gyroid pattern allowed obtaining values of fracture toughness higher than the concentric counterpart, independent of the infill density. In the case of an infill density of 60 %, the results of fracture toughness were similar to those obtained when a density of 80 % was used, implying a saving of material, for both concentric and gyroid pattens.