For the problem of mesh distortion when the finite element method (FEM) was applied in the simulation of extrusion forming, a novel material point method (MPM) was introduced. The extrusion forming processes under taper die and flat die were simulated by establishing models of material point and program written in the extrusion forming, and the deformation rules were obtained. Then, results of experiment and calculation were verified. Furthermore, the shape and height of extrusion part were obtained by simulating the cold extrusion forming with taper die. The results of simulation are in good agreement with those of experiment, and the maximum error is 0.52%. The deformation rule of extrusion part was obtained by simulating the cold extrusion forming with flat die. When the reduction is larger, the cold extrusion forming process is simulated successfully by MPM, but a mesh distortion appears by FEM. The results show that the MPM is feasible and effective for simulating the cold extrusion forming process and the mesh distortion can be effectively eliminated.
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