In a worldwide scenario where the environmental impact has a notable significance, the green tribology is, with no doubt, crucial. As the terms suggests, it refers to the all the tribological applications in favor of the sustainability. In this regard, the manuscript aims to investigate the tribological behaviour of four different samples, all composed of Polylactic acid but with different fillers as wood pine (BOR), bamboo (BMB), cork (KOR) and no fillers (PLA). The specimens were also subjected to a cycle of exposure to heat, cold and humidity in a range of 0 (no degradation) to 6 weeks accordingly to EN ISO 9142 standard. The tribological tests were performed in absence of any lubrication, coupling the specimens with a sphere of stainless steel AISI 420C. The volume loss, friction coefficient evolution (COF), wear rate and topography were analyzed finding out that the best performances were achieved by BMB and BOR, followed by KOR. In any case, COF and material loss were lower respect to the pure PLA, underling the positive role played by the reinforcements. On the other hand, the effect of degradation mechanism was almost influential on total wear. Besides, the abrasive mechanism induced by the kind of coupling, determined a notable increment of the arithmetical roughness (Ra), above all for PLA and KOR and by rising the number of weeks. Lastly, a linear correlation between mean friction and wear of the number of cycles was found out with determination coefficient (R2) equals to 0.88.
Tribological Behaviour of PLA Composites with Different Natural Fibers and Degradation Mechanisms
Marco De Stefano;Alessandro Sicilia;Alessandro Ruggiero
2024-01-01
Abstract
In a worldwide scenario where the environmental impact has a notable significance, the green tribology is, with no doubt, crucial. As the terms suggests, it refers to the all the tribological applications in favor of the sustainability. In this regard, the manuscript aims to investigate the tribological behaviour of four different samples, all composed of Polylactic acid but with different fillers as wood pine (BOR), bamboo (BMB), cork (KOR) and no fillers (PLA). The specimens were also subjected to a cycle of exposure to heat, cold and humidity in a range of 0 (no degradation) to 6 weeks accordingly to EN ISO 9142 standard. The tribological tests were performed in absence of any lubrication, coupling the specimens with a sphere of stainless steel AISI 420C. The volume loss, friction coefficient evolution (COF), wear rate and topography were analyzed finding out that the best performances were achieved by BMB and BOR, followed by KOR. In any case, COF and material loss were lower respect to the pure PLA, underling the positive role played by the reinforcements. On the other hand, the effect of degradation mechanism was almost influential on total wear. Besides, the abrasive mechanism induced by the kind of coupling, determined a notable increment of the arithmetical roughness (Ra), above all for PLA and KOR and by rising the number of weeks. Lastly, a linear correlation between mean friction and wear of the number of cycles was found out with determination coefficient (R2) equals to 0.88.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.