To enhance biodegradability of plastics and to utilize Centella spent (CTS) gainfully, green composites were prepared using high-density polyethylene (HDPE) and CTS. The green composites were fabricated by extrusion, followed by injection molding. HDPE/CTS composites were fabricated with 10, 20, and 30 wt% of CTS using maleic anhydride-grafted-polyethylene (MA-g-PE) as compatibilizer. The fabricated composites were tested for physicomechanical and tribological properties, which included water absorption, density, tensile properties, and three-body abrasive wear test. Tensile modulus of composites increased from 579 MPa to 950 MPa (64% improvement) with increase in filler addition from 0% to 30%. The experimentally obtained tensile property values including tensile strength, tensile modulus, and tensile elongation at break were compared with theoretical model values. The effects of 150, 300, 450, and 600 m abrading distances and 23.5 and 33.5 N normal loads at 200 r/min on the abrasive wear characteristics were studied using dry sand/rubber wheel abrasive test rig. Incorporation of CTS filler lowered the abrasion resistance of HDPE/CTS composites. The surface morphology of tensile-fractured specimens and worn surface features of composite specimens were examined by scanning electron microscopy
