INVESTIGADORES
BERNAL Celina Raquel
artículos
Título:
Effect of Microstructure on the Tensile and Fracture Properties of Sisal Fiber/Starch-based Composites
Autor/es:
V. ALVAREZ, A. VAZQUEZ Y C. BERNAL
Revista:
JOURNAL OF COMPOSITE MATERIALS
Editorial:
SAGE
Referencias:
Año: 2006 vol. 40 p. 21 - 35
ISSN:
0021-9983
Resumen:
In this study, the effect of microstructure on the tensile and fracture
properties of injection molded biocomposites consisting of starch-based matrix and
short sisal fibers has been investigated. Tensile tests are carried out on samples cut in
longitudinal (L) and transverse (T) directions with respect to the melt flow direction.
An increasing trend in Youngs modulus and tensile strength with fiber content
is found, irrespective of the sample orientation. In addition, this reinforcing effect
is more pronounced for L samples with many fibers mainly oriented longitudinally
to the loading direction. Quasistatic fracture tests are also performed on SENB
specimens with cracks propagating both parallel and perpendicular to the melt flow
direction. The stress intensity factor is found to increase with fiber content, and it
also depends on fiber orientation. The observed trend in fracture toughness with fiber
content and microstructure is explained in terms of the fiber pullout mechanism.
Puncture tests are carried out for all compositions. Injection molded composites
exhibit higher values of total fracture energy than neat matrix. Furthermore, fiber
orientation induces different patterns in the damage zone. Finally, several theoretical
models are used in this study to predict the elastic properties of these composites.