Thermal Effects on Tribological Behavior in Machining Natural Fiber Composites

Abstract Machining natural fibers reinforced plastic (NFRP) composites is nowadays a real challenge for academia and industries. These eco-friendly materials are emerging in automotive and aeronautical industries thanks to many benefits for sustainable development. It is then necessary to anticipate their machining processes for integrating them into the NFRP industrial production chains. This paper investigates the thermal effect on the machinability of unidirectional flax fibers reinforced polypropylene composites (UDF/PP) regarding to the cutting contact geometry. For this aim, orthogonal cutting process has been performed on UDF/PP composites at room and low temperature of composite samples. Cutting contact geometry has been explored by changing the tool rake angle. Results show that reducing the cutting temperature affects the chip morphology and improves the cutting behavior of flax fibers which ameliorates the machinability of UDF/PP composites. This machinability is also improved by cutting with a smaller positive rake angle that increases the cutting contact stiffness with flax fibers. This study allows determining a new relevant indicator parameter of NFRP machinability based on the cutting friction.