TRIBOLOGICAL AND MECHANICAL PERFORMANCE OF TiO₂ AND Al₂O₃-FILLED UHMWPE COMPOSITES FOR HEAVY-DUTY VEHICLE BODY LINER APPLICATIONS

Ultra-high-molecular-weight polyethylene (UHMWPE) is widely recognized for its outstanding abrasion resistance and chemical inertness; however, its relatively low stiffness and moderate thermal stability limit its performance as a structural liner material in heavy-duty vehicle bodies subjected to cyclic impact and sliding contact. This study investigates the effect of TiO₂ and Al₂O₃ micro-particle reinforcements, individually and in binary combination, on the tribological and mechanical properties of UHMWPE-based composites intended for load-bearing automotive liner applications. Seven composite formulations with filler contents ranging from 5 to 20 wt.% were fabricated by hot compression molding at 180 °C and evaluated for tensile strength, elongation at break, Shore D hardness, wear rate (pin-on-disc, 25 N / 0.5 m·s⁻¹), coefficient of friction (CoF), impact strength, and heat deflection temperature (HDT). The binary-filled UHMWPE-T10A10 composite exhibited the most favorable balance: tensile strength increased by 61.6% (36.2 MPa vs. 22.4 MPa for neat UHMWPE), Shore D hardness improved by 14 units, wear rate decreased by 59.8% (1.94 × 10⁻⁶ mm³/N·m), and HDT rose from 78 °C to 101 °C. These improvements are attributed to synergistic reinforcement and enhanced interfacial load transfer between the oxide particles and the UHMWPE matrix. The results confirm that dual-oxide UHMWPE composites represent a promising, cost-effective alternative to metallic and conventional polymer liners for dump truck bodies, mining conveyor scrapers, and heavy transport loading platforms.