The effect of Young’s modulus on the surface‐force‐induced contact radius of spherical glass particles on polyurethane substrates

The radius of contact, arising from surface force interactions, was determined using scanning electron microscopy for glass beads having nominal radii of 12 and 20 μm in contact with two polyurethane substrates, differing principally in Young’s modulus (3.83 and 41.7 MPa, respectively). It was found that the ratios of the contact radii scaled according to the model proposed by Johnson, Kendall, and Roberts [Proc. R. Soc. London Ser. A 324, 301 (1971)]. The works of adhesion calculated from these results were found to be approximately 0.12 J/m2.