부산대학교 도서관

The main theoretical aspects of porous and powder materials technological processing is worked out. The proposed material model is based on: - the four-parameter plasticity theory, which reflect the influence of porosity, resistance and the presence of dilatancy of solid phase deformation regime; - the dissipative potential and the load surface expression, that allow to take account such materials elastic - viscous - plastic properties; - the solid phase energy deformation speed with its subsequent over the representative element volume averaging. The peculiarity of this model is that the equilibrium flow concept elastic-viscous-plastic material is an alternative to its elastic-plastic deformation. The proposed equations are suitable for their effective practical using for digital models creation that based on existent software for the of equilibrium processes of compact materials deformation finite–element analysis. The practical use of the proposed methodologies made it possible to determine: - the regularities of the different modules material layers interaction during stamping of bimetallic blanks with an conical working surface; - the porosity distribution over the product volume at the final stage of radial extrusion of the bushings with an internal flange; - the effect of powder material decompression during reverse extrusion of cylindrical products.