Extraordinary Bauschinger effect in gradient structured copper

Bauschinger effect is a well-known phenomenon, in which the tensile stress is higher than the reverse compressive stress. Here we report that the gradient structured copper exhibits an extraordinarily large Bauschinger effect. We propose to use the reverse yield softening, Δσb, as a quantitative parameter to represent the Bauschinger effect. Δσb evolves in the same trend as the back stress with pre-strain, and can be used to evaluate the...