Influence of Annealing Time on Tensile Strength and Change of Dimensions of PLA Samples Produced by Fused Filament Fabrication

摘要

Annealing is a well-known technology of heat treatment, which is commonly used for metallic materials. Nowadays, with the growth of 3D printing technologies, the first experiments with annealing of plastic prints are starting to appear. One of the most important parameters of plastic annealing is the annealing time. This article deals with the experimental determination of the influence of annealing time on tensile strength and change of dimensions of printed samples from PLA. The samples were annealed in the industrial oven for 15, 30, 45, 60 and 240 minutes at 110°C. After gradual cooling in air, they were measured and tested on a tensometer, which produces stress-elongation curves. The measurement results showed that all annealed samples changed in size depending on the position at which they were printed. For all different annealing times, the deformations of the annealed samples were approximately the same. The tensile strength of all annealed samples increased compared to the non-annealed ones. Also, no dependence between tensile strength and annealing time was found.