Fig. 2: Failure of the bulk polymer.
From: Predicting frictional aging from bulk relaxation measurements
Deformation d of polypropylene spheres (as shown in Fig. 1a) as a function of the initially applied compressive force \({F}_{0}\). At small forces (\({F}_{0} < 10{N}\)), d increases with \({F}_{0}\) to the power of 2/3 (blue dashed line), corresponding to Hertz’s theory for elastic deformation. At larger forces, this changes into a linear increase (red dashed line), corresponding to plastic deformation (see Supplementary Fig. 10 for a linear-linear plot).
