New strategy for interconversion of positive, negative, and zero Poisson′s ratios

To address the problem that the positive, negative and zero Poisson′s ratios are difficult to adjust, a new conversion strategy is proposed based on re-entrant decagonal cellular structures composed of curved rods/ plates. A combination of experiments and numerical simulations are performed to verify that the Poisson′s ratios of the structures are different (the range includes positive, negative, and zero) under various rod curvatures. The absolute value of the Poisson′s ratios of such structure is found to decrease gradually with the increasing effective true strain, followed by the appearance of reversed Poisson′s ratios. Theoretical analysis is conducted to explain such phenomena, and a curvature effect is proposed.