Aging and Memory in a Mylar Sheet under Cyclic Compression

Aging is a ubiquitous property of disordered materials where they exhibit a logarithmic slowing down of dynamics. It has been observed that analogous disordered systems, such as crumpled mylar sheets, show a similar slowing down of dynamics when mechanically manipulated through an oscillatory driving. In this work, we investigate the evolution of crumples in a mylar sheet through cycles of strain. In our experiments, we can strain the sheet in two independent axes and image how the crumples change. We find that as the sheet is repeatedly strained, microstructural changes between cycles decrease, and eventually a steady state is reached. We find that increasing the amplitude of strain increases the timescale associated with finding this steady state.