Thiadiazole compounds and their derivatives have good
carrying
capacity and lubricating properties. Herein, polydopamine can be in
situ self-assembled onto gallium-based liquid metal (GLM) nanoparticles
via ultrasound treatment of bulk GLM nanoparticles in dopamine-containing
Tris aqueous solution followed by covalent bonding with a thiadiazole
dimer (DMCT) through Michael addition reactions. The as-prepared thiadiazole
dimer-functionalized liquid metal (GLM-DMCT) nanoparticles, with an
average particle size of 380 nm, can be used as nanoadditives in the
base oil (500SN). The tribological properties of GLM-DMCT as additives
were evaluated under various loads, temperatures, and frequencies,
and the results showed that GLM-DMCT additives have improved anti-friction
and anti-wear performances of 500SN. The coefficient of friction can
be reduced to 0.092 from 0.147 after adding 2 wt % GLM-DMCT, the wear
volume reduces by 89.7%, and the load-carrying capacity is increased
from 150 to 1050 N. The improved tribological performance is credited
to the formation of a stable, protective layer on the friction pair
via the complex tribo-chemical reaction of Ga, In, and S elements
of GLM-DMCT. Furthermore, the as-prepared GLM-DMCT exhibits good anti-corrosion
performance, which is attributed to the breaking of the disulfide
bond of DMCT, releasing the corrosion inhibitor DMTD during the corrosion
process.