Host: The Japan Society of Mechanical Engineers
Name : [in Japanese]
Date : September 11, 2022 - September 14, 2022
In general, sliding parts of machines should avoid wear particles entering into a contact area to enlongen lifetime of those parts. To observe wear particles which entering into a contact point by using optical microscope and high speed camera is thought to be one of the potential candidate to elcidate life of the parts. However, it is challenging to see those particles of sub-micrometer diameter because of diffraction limit. The authors have been trying to develop iFLAT (intelligent Fluorescent Light Assisted Tribometer) to orvercome this diffraction limit. It can observe fluorescent stained particles which emits fluorescent light by 532 nm laser. The laser irradiates the friction surface through the objective lens, and the reflected light passes through the filter and enters the camera. The reflected laser light is blocked by a filter, and the imitated wear particles that emit fluorescence are selectively observed.
In this study, we clarified the effect of outside oil film thickness on the number of particles entering under poor lubrication conditions and the mechanism of this effect. In-situ observation of the contact area using 0.8 μm and 0.02 μm particles revealed four behaviors: backflow, lateral flow, incoming flow, and accumulation of particles.
