Mechanical operations such as in the internal combustion engine require robust conditions especially gas
engines where it can achieve high combustion temperatures. Materials for pistons rings and cylinder liners
are carefully selected to withstand high combustion temperatures and severe wear and friction operation.
Surface treatments by applying coats of chromium and DLC to the base material introduce protection to
wear, fatigue and corrosion. In this experimental study, high speed steel is simulated as the piston rings
and Ni-resist cast iron as the cylinder liner. A tribology study on the effects of bio-lubricant based palm oil
combined with 1,3-diethyl imidazolium diethylphosphate on uncoated/coated high speed steel on Ni-resist
Cast Iron was carried out using the Reciprocatory Friction Monitoring Machine. The experimental
conditions were as follows; normal loads from 10N to 100N, sliding speed was 2000 rpm, with test
duration of 30 minutes, approximately 240 meters of sliding distance, room temperature of 30!C and the
test temperature of 150!C. The wear and friction curves were plotted and discussed. Used oil samples were
checked for ferrous metal debris using the PQ/PQ90A dual-coil magnetometer.