Experimental investigation of the tribological properties of polymer based journal bearings at different loads and speed

In this thesis, it is aimed to investigate the tribological properties of polymer-based journal bearing materials with self-lubricating properties at specified loads and speeds. For this purpose, pure PTFE, PTFE + 25 % Carbon, PTFE + 35 % Carbon, PTFE + 15 % Glass fiber, PTFE + 25 % Glass fiber, PTFE + 40 % Bronze, PTFE + %, 60 Bronze doped journal bearing which are widely used and subject to different studies in the literature, specimens were designed and supplied The experimental conditions in which the samples will be tested, the relevant studies in the literature were examined, and the conditions in which the samples were not tested before were determined. A journal bearing testing aparatus was designed and manufactured, in which the temperature, vertical force and velocity values to be saved during the experiments were constantly monitored. Samples according to the determined test conditions; they completed the 5000 m sliding distance under 3 different loads of 75 N, 50 N and 25 N and at 3 different speeds as 0.3 m/s, 0.6 m/s and 0.9 m/s. The friction coefficient, weight loss, surface roughness, wear amount and wear rates of the samples were determined under the specified conditions, the effects of the additives added to PTFE on the mechanical properties were evaluated and the changes in the surfaces were analyzed by scanning electron microscope (SEM).