THERMAL STRESSES IN THIN AUXETIC PLATES

This article investigates the effect of auxeticity on the thermal stresses of isotropic plates. The thermal stress is non-dimensionalized against the coefficient of thermal expansion, the change in temperature and at least one of the moduli so as to express the dimensionless thermal stresses solely in terms of Poisson's ratio of the plate material. Results show that increasing auxeticity leads to mild and significant drop in the thermal stresses under the conditions of constant Young's modulus and constant shear modulus, respectively. However, increasing auxeticity causes increase in the thermal stress under the condition of constant bulk modulus. It is also shown that increasing auxeticity under the condition of constant product of all the three moduli reduces the thermal stress if Poisson's ratio falls within a wide range of -1 and 0.303. These results suggest that, under most circumstances, the replacement of conventional plate materials with auxetic solids is useful for reducing thermal stresses therein. The use of auxetic materials, therefore, provides an additional choice for the reduction of thermal stresses in plates other than selecting materials of lower modulus and low coefficient of thermal expansion.