Open die forging of porous materials

It is the objective of this work to suggest and apply an extended formulation for the evolution of the material density in an open die forging of porous axisymmetric solid with Gurson’s yielding model. An admissible porous-dependent velocity field is obtained and applied to form the constitutive behavior of the compressible material. Concurrently, an admissible stress field of the yielded material is used to estimate the effect of the hydrostatic stress on the bulk flow. Such a combination of the dual bounds enables one to assess the non-steady loading path in terms of the current porous state and the geometry of the workpiece, regardless of the mechanism by which the densification process is achieved. Emphasis is given to the use of the newly porous-dependent shear boundary condition along with some classical interfacial friction models. The suggested procedure to simulate the evolution of the densification during the forging process is compared with FEM solutions and self-generated data.