Fig. 2. (a) Stress–strain curve of a EA0.2-0.05(2.61) sample in a step cyclic loading test; (b) images of EA0.2-0.05(2.61) at the minimum and maximum deformation in the same step cyclic loading test; (c) chromatic change curve of EA0.2-0.05(2.61) sample in step cyclic loading test; (d) 3D color-stress map of the EA0.2-0.05(2.61) sample. The black dots are the experimental points and the green curves are the fitted curves for the relaxation. The color coding represents the nominal stress level. The grey dashed line corresponds to the boundary of physical meaningful chromatic coordinates.
