Tribological and thermogravimetric performance of flax/bamboo hybrid composites for gear applications: Influence of the stacking sequence

Abstract Plastic gears are widely used for various applications; however high environmental problems, low working life, and weak wear performance caused by high contact friction and running temperatures limited their use, particularly in medium‐to‐high power transmission. This study is an initial approach to develop and investigate hybrid woven‐natural fiber reinforced polymer composites for medium‐to‐high power transmission gears. Also, no research has been proposed to investigate the thermal stability and degradation, and wear performance of hybrid flax(F)/bamboo(B) woven composites. The current work seeks to regulate the wear, friction, and thermal stability of flax/bamboo hybrid epoxy composites by carefully selecting the stacking sequence. The composites were stacked in following sequence: F/B/B/F, B/F/F/B, F/F/B/B, and F/B/F/B. The tribological and thermal performance of the composites were investigated using a pin on a rotating disc test (ASTM G99) and thermogravimetric analysis (ASTM E 1131‐03) under ambient conditions. Results revealed that the stacking sequence significantly influenced the thermal stability and degradation, and wear properties. The thermal stability of B/F/F/B was found to be higher, demonstrating the increase in the amount of char residue in placing bamboo lamina as the skin. Tribological results indicate that the hybridization of flax/bamboo fibers into an epoxy matrix enhanced the wear performance. Also, B/F/F/B exhibited the maximum reduction in coefficient of friction and specific wear compared with pure epoxy (26%–50% and 65%–94%) and F/F/B/B (16%–49% and 21%–40%). The morphology of worn surfaces was studied in detail to correlate the specific wear rate with wear mechanisms. Based on the improved thermal and wear resistance, bio‐composite with B/F/F/B stacking can be used for gear applications.