Effects of geometry and thermal aging on the strength of 3D-printed polymer parts

Abstract

Based on advantages of additive manufacturing (AM), this technology is becoming one of the most popular and preferable manufacturing processes in different industries. Although AM was introduced for fabrication of prototypes, it has been used for production of end-use products. Consequently, the mechanical strength of AMed parts has become of significant importance. In the present study, Influence of geometry and thermal aging on the mechanical strength of AMed parts has been investigated. To this aim, polylactic acid material was used to print specimens based on fused deposition modeling process. Since geometry of AMed parts has effect on their mechanical behavior, the specimens with three different geometries are fabricated and examined. Particularly, dumbbell-shaped, smooth, and V-notched specimens were subjected to tensile load under static loading conditions. In addition, in order to evaluate Influence of thermal environment, we carried out an accelerated thermal aging within temperatures of -5°C to 35°C, which is below glass temperature of the examined material. Experimental results showed different fracture behaviors and tensile strength due to the different geometries. Moreover, based on a series of tests, the failure behavior of original and aged specimens are determined. The outcomes of this study confirmed that the geometrical appearance and environmental working conditions of AMed parts must be taken into account in the design of these components.