FIG. 1.

Elastic bilayer wrinkling generates film thickness oscillations that are overall in phase with the substrate deformation when the film is thin. Top row: maximum in-plane principal stress (normalized to half of the substrate’s shear modulus) for two different circular wrinkling problems. $r_s^0/{\tau }^0$ is the initial substrate radius in units of the initial film thickness, and E_f /E_s is the stiffness contrast. Insets plot the sign of the stress-tensor component s_rr, with yellow indicating positive values (tension) and purple indicating negative values (compression). Bottom row: substrate radius (blue) and film thickness (red), normalized to their average values, for the same two wrinkling problems. Note the different scales on left and right axes.