Measurements of Distributions of Real Contact Area Using Polymer Films

In a previous paper, we developed a new method of measuring a distribution of real contact area between two solid surfaces using PET film. Tiny protuberances on the PET film were produced to reduce its friction. In the measurement, these protuberances could not be distinguished from the real contact area. Thus the calibration was needed to remove the effect of the protuberances before the experiments. In this paper, we produced four kinds of polymer films without the protuberances on their surfaces. The real contact area was measured with those polymer films. We discussed the effect of the mechanical properties of those polymer films on the measurement. It was found that the elongation property of the polymer was important to this kind of measuring method.