Plane strain extrusion by sequential limit analysis
The analysis of plane strain forward extrusion through wedge shaped dies is implemented by using a finite element procedure based on a dual (upper bound) formulation. Since the von Mises yield criterion is employed and expressed in an inequality form, stresses do not appear in this upper bound formulation. As a result, neither complicated stress updating nor rigid zone treatment is needed in this approach. The author incorporates the effect of material strain hardening in the analysis by updating local yield stresses stepwise with deformation history. The computed results are in good agreement with existing analytical solutions. Finally, the author investigates the effects of friction, die semiangle, height reduction ratio and material strain hardening on the extrusion load of aluminum.
scientific article; zbMATH DE number 1076448