Abstract: Mechanical systems are always deal with wear and friction as the liability. The basic principle of the mechanical system is the surface interaction between surfaces which have a frictional force resulting in fatigue and damage to the mechanical components. Lubricant is used to minimize friction in order to solve the problem. A comparative friction characteristic analysis was then conducted to assess the coefficient of friction (COF) between Aluminum Alloy 5083 block and SKD 11 disk using two types of lubricant, that is SAE40 engine oil and RBD palm oil. The thickness of the oil film could be predicted in order to observe the influence of the different lubricants used. Pit pattern surface is required to research the function of the pit as a lubricant reservoir. The experiment was carried out in the laboratory according to the ASTM G99. Load is applied to experiments with loads of 1 kg, 5 kg and 10 kg, in order to find a COF correlation under different application condition. The rotational speed is held constant at 3m/s during the experiment. The results obtained revealed that when using RBD palm oil as a lubricant, the COF between block and disk is lower than when using SAE40 engine oil as a lubricant. The experimental result showed that RBD palm oil can minimize friction much lower than SAE40 engine oil. Based on the results of the comparison analysis on the flat surface and pit pattern surface, the finding revealed that the pit pattern may serve as a lubricant reservoir to retain and store the lubricant for longer than the flat surface that helps to reduce friction.
Keywords: Friction; palm olein. Pin on disk; tribology; fluid film