Controllable thermal expansion of large magnitude in chiral negative Poisson's ratio lattices. Issue 7 (17th April 2015) - Ha, Chan Soo
Abstract Lattices of controlled thermal expansion are presented based on planar chiral lattice structure with Poisson's ratio approaching −1. Thermal expansion values can be arbitrarily large positive or negative. A lattice was fabricated from bimetallic strips and the properties analyzed and studied experimentally. The effective thermal expansion coefficient of the lattice is about α=−3.5×10−4K−1. This is much larger in magnitude than that of constituent metals. Nodes were observed to rotate as temperature was changed corresponding to a Cosserat thermoelastic solid.