Colin Rogers University of NSW On a Novel Class of Nonlinear Elastic Materials Wednesday 9th May 14:05-14:55pm, Eastern Avenue Lecture Theatre. A class of infinitesimal B\"acklund transformations is used to construct model constitutive laws for which the nonlinear system describing uniaxial wave propagation may be reduced to a canonical form associated with Hookean response in an asymptotic limit. The stress strain laws are given parametrically in terms of elliptic functions. Importantly, these models can allow a change in concavity in the stress strain law. Such behaviour can occur, for instance, in the loading and unloading regimes of superelastic nickel-titanium. Biocompatibility of the latter has led to its widespread use in medical devices (stents etc).