A Homodyne Quadrature Laser Interferometer for Micro-Asperity Deformation Analysis

Sensors

Aljaž PogaČnik¹  Tomaž Po៪r²  Mitjan Kalin² 

[1] Iskra Mehanizmi d.o.o., Lipnica 8, Kropa 4245, Slovenia; E-Mail:;Faculty of Mechanical Engineering, University of Ljubljana, AškerČeva 6, Ljubljana 1000, Slovenia; E-Mails:

关键词: micro-asperity;    deformation;    real contact area;    roughness;    polymer;    creep;    tribology;    laser interferometry;    homodyne detection;    displacement;   

DOI  :  10.3390/s130100703

来源: mdpi

【 摘 要 】

We report on the successful realization of a contactless, non-perturbing, displacement-measuring system for characterizing the surface roughness of polymer materials used in tribological applications. A single, time-dependent, scalar value, dubbed the collective micro-asperity deformation, is extracted from the normal-displacement measurements of normally loaded polymer samples. The displacement measurements with a sub-nanometer resolution are obtained with a homodyne quadrature laser interferometer. The measured collective micro-asperity deformation is critical for a determination of the real contact area and thus for the realistic contact conditions in tribological applications. The designed measuring system senses both the bulk creep as well as the micro-asperity creep occurring at the roughness peaks. The final results of our experimental measurements are three time-dependent values of the collective micro-asperity deformation for the three selected surface roughnesses. These values can be directly compared to theoretical deformation curves, which can be derived using existing real-contact-area models.

【 授权许可】

CC BY   
© 2013 by the authors; licensee MDPI, Basel, Switzerland.