Harnessing nano oil reservoir network for generating low friction and wear in self-mating alumina

•Fomblin® Y25/6 oil is an excellent lubricant for self-mating nanoporous alumina.•90% Al2O3 relative density is the optimal in the range of 70–99.5% for achieving best tribological properties.•Friction coefficients decreased with increase in normal loads (10–220 N) and sliding frequencies (1–24 Hz).•Lowest friction coefficient of 0.025 was recorded for 95% dense self-mating lubricated Al2O3.•Wear occurred by intergranular fracture in 70–90% dense Al2O3 and transgranular fracture in 95–99.5% dense Al2O3.