Current study investigates tribo-phenomena at sliding interface of Al2124-17SiCp disc and WC-6Co pin and explores suitability of nano-oil aerosols as lubricants. They form chip-tool tribo-pair in machining. Ploughing, adhesion, abrasion were predominant under dry sliding. Adhesion and friction-coefficient (COF) were severer with higher normal load and lower sliding velocity. Aerosol of palm-oil arrested adhesion of aluminium on carbide pin and reduced COF by 80–82% through film-lubrication but at low load conditions. Diamond/graphite nanoparticles (1 wt%) suspension helped palm-oil sustain film-lubrication at sliding interface even in extreme conditions, reducing COF further and arresting adhesion phenomenon. Rolling of near-spherical nano-diamonds or basal-plane shearing within graphite nano-platelets caused additional reduction in friction. Graphite nano-aerosol was superior and similarly effective in high-speed milling as SQL-medium. © 2020 Elsevier Ltd