Mullins effect

The Mullins effect is the stress-strain response in filled rubbers which typically depends on the maximum loading previously encountered. The phenomenon, named for British rubber scientist Leonard Mullins, can be idealized for many purposes as an instantaneous and irreversible softening of the stress-strain curve that occurs whenever the load increases beyond its prior all-time maximum value. At times when the load is less than a prior maximum, nonlinear elastic behavior prevails.