High‐Temperature Tribological Performance of Short Bamboo Fiber‐Reinforced Polymer Composite

ABSTRACT This study investigates the ball‐on‐disk tribological behavior of short bamboo fiber‐reinforced polypropylene matrix composite under temperatures ranging from room temperature to the high temperature of 175°C, with a particular focus on elucidating their high‐temperature failure mechanisms. The results show that within the temperature range from room temperature to 175°C, the wear rate increased monotonically from 0.70 × 10 −3 to 6.13 × 10 −3 mm 3 /(N·m) with rising temperature, while the frictional coefficient exhibited an initial decrease followed by an increase, with values of 0.21 → 0.17 → 0.22. A comprehensive analysis of the mechanical and chemical characteristics of both the composite and its constituent materials reveals that high temperatures significantly soften the polypropylene matrix and the whole composite. Additionally, slight thermo‐oxidative degradation of the polypropylene matrix occurs, while the bamboo fibers retain the mechanical and chemical stability even at high temperatures. Consequently, matrix softening is identified as the primary factor contributing to increased wear and the deterioration of wear resistance at high temperatures. Moreover, this study uncovers the temperature‐dependent evolution of the frictional coefficient governed by the competing mechanisms of matrix softening and adhesive wear. These findings provide theoretical guidance for the application of natural fiber‐reinforced composites in high‐temperature environments such as braking systems.