LB13930 -
Prince Rupert’s drops, also known as Dutch tears, are tadpole-shaped glass droplets that are able to withstand strong blows to their main bodies, but explosively crumble upon the slightest damage to their tails. Similar behavior, albeit less spectacular, is observed in various everyday situations and exploited in industrial applications such as safety glass or “Gorilla glass” covers for smartphones. This, sometimes phenomenal, response is due to a persistent stress remaining in the material, which cannot fully relax to equilibrium and is, often deliberately, inflicted during the production process, e.g. by fast solidification from the melt. These macroscopic material properties are thus imprinted by the history- or process-dependent microstructure and cannot be relieved. Despite large efforts, residual stresses have long defied a thorough understanding. Now, experiments, simulations and theoretical calculations have been combined to shed light on the microscopic origin and the generic mechanism leading to macroscopic residual stresses in glasses and hence their amazing, but also scientific and technologically interesting, rheological behavior.
