Drilling performance and wear behavior of rice straw waste reinforced polymer composites

Abstract The utilization of rice straw waste promotes waste valorization, reduces environmental pollution caused by open‐field burning, and supports the development of sustainable engineering materials. This study evaluates the machinability and tribological behavior of water‐treated rice straw reinforced polymer composites (RSPCs), focusing on drilling performance and wear mechanisms. Unlike previous studies primarily addressing composite fabrication and mechanical characterization, this work investigates secondary manufacturing behavior, which is essential for industrial implementation. The novelty lies in comprehensively evaluating drilling performance in terms of thrust force, hole quality, and material removal rate, along with drilling‐induced damage and wear characteristics. Water‐treated rice straw with weight fractions of 50% and 60% was used to fabricate epoxy‐based composites. Drilling experiments were conducted at feed rates of 50, 75, and 100 mm/min, spindle speeds of 1000, 1500, and 2000 rpm, and drill diameters of 7.5 and 9.5 mm. Machinability was assessed through thrust force, hole quality, and material removal rate. Tribological behavior was evaluated using a pin‐on‐disc tribometer against a hardened gray cast‐iron plate at sliding speeds of 0.1, 1.0, and 1.5 m/s and sliding distances of 1000 and 1500 m. The 60% stubble‐fraction composite exhibited an average reduction of approximately 8% in drilling thrust force compared with the 50% composite, indicating improved machinability. Specific wear rate increased by approximately 40% with increasing sliding speed from 0.5 to 1.5 m/s. Worn‐surface analysis revealed abrasive and adhesive wear, matrix cracking, and fiber pull‐out. Overall, water‐treated RSPCs demonstrate promising machinability and wear resistance for semi‐structural and tribological applications under low‐to‐moderate loading conditions.