Thermal effect on the tribo-mechanical behavior of natural fiber composites at micro-scale

Abstract

This paper aims to explore the thermal influence on the micro-tribo-mechanical behavior of natural fiber composites. Nanoindentation and scratch-test are used to characterize flax fibers reinforced polypropylene (PP) composites. Results show a different thermo-mechanical behavior between flax fibers and PP matrix. While the stiffness of PP matrix decreases by increasing the sample temperature, the stiffness of flax fibers shows an increase then a decrease by changing the sample temperature from 25 °C to 100 °C with a maximum at 60 °C. This attests to a modification of the chemical composition of flax fibers when increasing the temperature. The specific thermo-mechanical behavior of flax fibers affects their friction comportment at a high sliding speed which demonstrates that the tribology of NFRP composites is thermo-mechanical-dependent.