Adjustable and negative thermal expansion from multilayered systems

A construct in the form of a multi-layered system built from conventional materials having different mechanical and thermal properties is proposed. This construct can exhibit predetermined values of thermal expansion which could also be negative. It is shown that for maximising negative thermal expansion (NTE) there should be a combination of thin layers of stiff materials having a high positive coefficient of thermal expansion (CTE) bonded with thicker layers of a soft material having low CTE values and, more importantly, having Poisson's ratio as high as possible. (C) 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim