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

Abstract

This study unleashes the potential of nanoporous connected networks as excellent oil reservoirs for reducing friction and wear in Al2O3-Al2O3 tribo-pairs. Alumina were fabricated via slip casting and sintering to generate wide-ranging densifications (70-99.5%) and slid in a reciprocating flat-on-flat configuration. Friction coefficients (FCs) lie between 0.025 and 0.37 which decreased with an increase in normal load (10-220 N), lubricant's viscosity (19, 289 mPa.s) and sliding frequency (6, 12, 24 Hz). A central finding is that FCs of infused specimens are smaller than those of surface lubricated. Wear rates decreased from 10-5 to <10-8 mm3.N-1.m-1 for an increase in Al2O3 density. Wear occurred predominantly via intergranular and transgranular fracture modes as revealed by the electron microscopy studies.