In theories of failure (e.g von-Mises, Tresca, Max. principal stress etc), yield funcion, f(sigma ij, Y) = 0 is plotted in principal stress space (sigma 1, sigma2 and sigma 3). Why shouldn't we express the same yield function, f(epsilon ij, epsilon Y) = 0 and plot in principal strain space?
Y = Yiled stress, sigma ij = stress ij, epsilon ij = strain ij. and espsilon Y = Yield strain = Y/E, E = Young's modulus
Any thoughtful comments???