DESIGN OPTIMIZATION OF MATERIAL WITH ZERO THERMALEXPANSION COEFFICIENTS AND DESIGN VERIFICATION WITHNUMERICALLY SIMULATED EXPERIMENTS

Materials with zero thermal expansion coefficients benefit to improve the geometrical stabilities of aeronauticand astronautic structures and electric equipment under great temperature changes. The microstructure of materials withzero thermal expansion coefficients is designed using a topology optimization method which consists of finding the distribution of three material phases in the design domain. These material phases include two different material phases and a voidphase. The effective properties of material structures are determined using the numerical homogenization method based ona finite-element discretization of the base cell , and the optimization problem is solved with the feasible direction method.The dependence on initial design is investigated , and some possible reasons causing the problem are discussed. The thermalexpansion behavior of the material with designed microstructures is tested by numerically simulated experiments and , thethermal expansion coefficients are obtained through analyzing the deformation of the materials caused by temperaturechange. These numerically simulated experiments verified the characteristic of zero (low) thermal expansion behavior ofthe designed material , which shows that the topology optimization method is a valid and effective method for microstructure design of materials with zero thermal expansion coefficients.