Abstract:
Natural fibre composites are fast emerging as a viable alternative to traditional
materials and synthetic composites. Their low cost, lightweight, good mechanical
performance and their environmentally friendly nature makes them an ideal choice for
the automotive sector. The automotive industry has already embraced these composites
in production of non-structural components. At present, however, research studies into
composites made of natural fibres/bio-sourced thermoplastic resins are at infancy stage
and such works are rare in the literature.
This study therefore focuses on the mechanical properties of poly(lactic) acid (PLA) flax
reinforced composites for structural loaded components. The aim was to investigate the
performance of flax/PLA biocomposites subjected to localized low velocity impacts. To
start with, a detailed literature study was conducted covering biocomposites and PLA in
particular. Next, a series of composite samples were manufactured. Morphological and
thermal studies were also conducted in order to develop an in-depth understanding of
their thermo-mechanical properties, including crystallinity, thermal response and their
related transition temperatures. This was followed by localized impact studies. The
influence of temperature, water uptake and strain rates to the material tensile strength
and modulus, as well as the damage characteristics and limits that lead to failure were
studied. Furthermore, in the present work different methods and existing material
models to predict the response of biocomposites were assessed. A case study was then
performed using these models to understand, develop and improve the side crash
performance of a superlight city car prototype. ...[cont.]
