Effects of annealing temperature and duration on mechanical properties of PLA plastics produced by 3D Printing

Abstract

This study aims to investigate the effect of annealing temperature and duration on the mechanical properties of PLA (polylactic acid) plastics produced by a 3D (three-dimensional) printer. For this purpose, PLA samples were annealed at 70 °C, 85 °C, and 100 °C temperatures and for 30, 60, and 90-minute durations. As a result of the study, it was shown that the annealing process has a significant effect on the mechanical properties of PLA plastics. Compared to the control sample, an increase of 48% in tensile stress, 78% in the modulus of elasticity, 28% in Shore D hardness value, and 41% in bending stress was observed. In particular, the highest mechanical properties of PLA plastics were reached after applying the annealing process at 85 °C temperature and for 90 minutes. These results demonstrate the advantages of using 3D printers in the production of products requiring high durability in industrial applications. Moreover, the study findings provide an important method for optimizing the mechanical properties of materials produced with 3D printer technology.

Keywords

• Annealing process
• mechanical properties
• PLA plastics
• fused deposition modeling
• 3D printing.

References

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