TY - JOUR
T1 - Exploring the morphology of flax fibres by X-ray microtomography and the related mechanical response by numerical modelling
AU - Richely, E.
AU - Bourmaud, A.
AU - Dhakal, H.
AU - Zhang, Zhong Yi
AU - Beaugrand, J.
AU - Guessasma, S.
N1 - Appendix is supplementary materials
PY - 2022/9/1
Y1 - 2022/9/1
N2 - The external shape and internal lumen of flax fibres are investigated using X-ray microtomography (µ-CT) and finite element (FE) modelling. µ-CT reveals an intricate flax fibre and lumen morphology, with mean porosity contents between 0 and 7.2%. The FE model is based on 3D volumes obtained by X-ray µ-CT and tensile testing in the elastic domain. Numerical results demonstrate the decrease of stiffness as a combined effect of porosity and stress heterogeneity triggered by geometrical considerations. Moreover, stress concentrations induced by both surface roughness and complex lumen shape were observed, highlighting their possible implication in failure mechanisms. However, Young's moduli are overestimated compared to experimental curves and non-linearities are not considered by the rather strong hypothesis of this model (linear elastic material: no viscosity, plasticity or damage mechanisms taken into account). Future work should include the orientation and reorientation of cellulose microfibrils upon tensile testing, as well as damage mechanisms.
AB - The external shape and internal lumen of flax fibres are investigated using X-ray microtomography (µ-CT) and finite element (FE) modelling. µ-CT reveals an intricate flax fibre and lumen morphology, with mean porosity contents between 0 and 7.2%. The FE model is based on 3D volumes obtained by X-ray µ-CT and tensile testing in the elastic domain. Numerical results demonstrate the decrease of stiffness as a combined effect of porosity and stress heterogeneity triggered by geometrical considerations. Moreover, stress concentrations induced by both surface roughness and complex lumen shape were observed, highlighting their possible implication in failure mechanisms. However, Young's moduli are overestimated compared to experimental curves and non-linearities are not considered by the rather strong hypothesis of this model (linear elastic material: no viscosity, plasticity or damage mechanisms taken into account). Future work should include the orientation and reorientation of cellulose microfibrils upon tensile testing, as well as damage mechanisms.
KW - Finite element analysis
KW - Natural fibers
KW - Stress concentrations
KW - X-ray microtomography
UR - http://www.scopus.com/inward/record.url?scp=85132873174&partnerID=8YFLogxK
U2 - 10.1016/j.compositesa.2022.107052
DO - 10.1016/j.compositesa.2022.107052
M3 - Article
AN - SCOPUS:85132873174
VL - 160
JO - Composites Part A: Applied Science and Manufacturing
JF - Composites Part A: Applied Science and Manufacturing
SN - 1359-835X
M1 - 107052
ER -