Tribological behaviour of injection moulded composite fabricated using bio-fiber (flax fiber), bio-filler (halloysite nanotube), and biopolymer (polylactic acid)

Abstract This study investigates the wear and frictional behavior of the flax fiber (FF)/polylactic acid (PLA)-based green composite filled with bio-filler, namely, the halloysite nanotube (HNT). The HNT/FF-PLA composite was fabricated using injection molding, considering the fixed injection pressure (90 bars), speed (60 mm sec −1 ), and temperature (165 °C). The HNT/FF-PLA composite was engineered with an FF length of 5 mm and 20% fiber loading. This study examined the wear and frictional behavior of engineered HNT/FF-PLA composite by exploring the intrinsic influences of tribo parameters such as the sliding speed (1 to 3 m s −1 ) and the applied load (10 to 30 N). The HNT/FF-PLA composite was developed by varying the HNT filler as 1, 1.5, and 3 wt%. The wear responses, such as the coefficient of friction (COF) and specific wear rate (SWR) were considered as the performance parameters to be optimized through response surface methodology (RSM). The morphology of the HNT/FF-PLA composite worn test specimens was examined by scanning electron microscope (SEM). The primary purpose of this study is to optimize the wear and frictional behavior of the engineered HNT/FF-PLA composite, advancing its application as a sustainable material with superior tribological performance. The results highlight the influence of HNT filler, sliding speed, and load on the COF and SWR, where optimal parameters were identified using the RSM. All the process parameters were found to be significant for both COF and SWR. The minimum COF was found at a sliding speed of 1.007 mm s −1 ., load of 25.32 N, and filler wt% of 1.007. For SWR, the optimal parametric combination is 2.986 m s −1 ., 29.45 N, and 1.66 wt%.