Fig. 4
The kinematics of two phases constituting a mixed material. In the solid phase, the current micro-volume dΩt is related to the original volume \(\mathrm {d}\Omega _{0}^{s}\) by the solid deformation gradient tensor Fs. In the fluid phase, it is associated with the original volume \(\mathrm {d}\Omega _{0}^{f}\) by the fluid deformation gradient tensor Ff. Generally, \(\mathrm {d}\Omega _{0}^{s}\) and \(\mathrm {d}\Omega _{0}^{f}\) don’t coincide