Creep behaviour of a polymer used for 3D printing

ABSTRACT In recent years, additive construction or 3D printing technology is being widely used for manufacturing goods. This construction procedure has and will have a great industrial impact. There are several 3D printing processes, and among of them the most known is called Fused Deposition Modeling (FDM). The objective of the present paper is oriented to the experimental characterization of the mechanical properties of pieces constructed by means of 3D printing using thermoplastic polymers. Although there are many studies about the characterization of mechanical properties in 3D printed parts, it should be noted that there is quite a little effort in evaluating the creep effect in 3D printed specimens. In this work the creep properties of the polylactic acid (PLA) are studied. This material is a thermoplastic and biodegradable biopolymer used in both amorphous and crystalline states, which has many technological applications. The tensile creep tests are performed at a temperature of 303K and at corresponding levels of tension between 25% and 50% of the yield strength of PLA. Standard specimens constructed with different layouts of plastic filament deposition are employed.