Study of the annealing influence on the mechanical performance of PA12 and PA12 fibre reinforced FFF printed specimens
ISSN: 1355-2546
Article publication date: 19 October 2020
Issue publication date: 28 November 2020
Abstract
Purpose
The purpose of this study is to evaluate and compare the mechanical performance of FFF parts when subjected to post processing thermal treatment. Therefore, a study of the annealing treatment influence on the mechanical properties was performed. For this, two different types of Nylon (PA12) were used, FX256 and CF15, being the second a short fibre reinforcement version of the first one.
Design/methodology/approach
In this study, tensile and flexural properties of specimens produced via FFF were determined after being annealed at temperatures of 135°C, 150°C or 165°C during 3, 6, 12 or 18 h and compared with the non-treated conditions. Differential scanning calorimetry (DSC) was performed to determine the degree of crystallinity. To evaluate the annealing parameters’ influence on the mechanical properties, a full factorial design of experiments was developed, followed by an analysis of variance, as well as post hoc comparisons, to determine the most significative intervening factors and their effect on the results.
Findings
The results indicate that CF15 increased its tensile modulus, strength, flexural modulus and flexural strength around 11%, while FX256 presented similar values for tensile properties, doubling for flexural results. Flexural strain presented an improvement, indicating an increased interlayer behaviour. Concerning to the DSC analysis, an increase in the degree of crystallinity for all the annealed parts.
Originality/value
Overall, the annealing treatment process cause a significant improvement in the mechanical performance of the material, with the exception of 165°C annealed specimens, in which a decrease of the mechanical properties was observed, resultant of material degradation.
Keywords
Acknowledgements
Author gratefully acknowledge the funding of Project POCI-0145-FEDER-016414-FIBR3D-Additive manufacturing based on hybrid processes for long or continuous fibre reinforced polymeric matrix composites, co-financed by Programa Operacional Regional de Lisboa (LISBOA 2020) and by the Project NORTE-01-0145-FEDER-000022-SciTech, cofinanced by NORTE2020, through FEDER.
Citation
Ferreira, I., Melo, C., Neto, R., Machado, M., Alves, J.L. and Mould, S. (2020), "Study of the annealing influence on the mechanical performance of PA12 and PA12 fibre reinforced FFF printed specimens", Rapid Prototyping Journal, Vol. 26 No. 10, pp. 1761-1770. https://doi.org/10.1108/RPJ-10-2019-0278
Publisher
:Emerald Publishing Limited
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