Investigation of Friction Phenomena by Using Acoustic Emission Method

Frictional damage in bearing is the leading cause of shutdown for industrial machineries including car engines. Early detection of this kind of damage may reduce maintenance costs and prevent unpredicted shutdown. Recently, researchers have been interested in using acoustic emission method, due to its high sensitivity, for condition monitoring of working machineries. In this study, the friction process is simulated by an experimental setup and its acoustic emissions have been analyzed to recognize which mechanisms affecton the acoustic emission signals. The results show that the signal waveforms varies greatly with initiation of damage in the frictional surfaces hence, damage process can be detected as early as it begins. In addition, the parameters affecting on friction, such as surface material, moving speed, frictional force, and lack of lubricant have sensible effect on the emission signals, so that, the frictional condition can be evaluated by monitoring and analyzing the signal waveforms.