Homogenizing Inhomogeneous Wrinkles

Homogenizing Inhomogeneous WrinklesUnderstanding the commonplace mechanical instability known as “wrinkling” has the potential to impact numerous materials and technological applications, such as optical surfaces, adhesives and flexible electronic devices. Understanding how wrinkles change with strain is important for many of these applications. While homogeneous strain will result in a homogeneously wrinkled surface, a systematic understanding of pre-existing strain inhomogeneity, which is commonly found in practical materials, has remained elusive.  Crosby, leading a collaborative effort in the Materials Research Science and Engineering Center on Polymers at UMass, developed novel fabrication methods to find that a surface with inhomogeneously distributed wrinkles will develop a surprising pattern of wrinkles on the surface, in which the wrinkles have exhibit homogeneous geometric dimensions at very small applied strains (~6%).