Deformable coated materials hold promises for numerous new technologies. In this research, extrusion of polymer coated metal rods was investigated. Analytical models based on upper bound method were developed to evaluate axisymmetric conical die extrusion of precoated materials. The rigid-plastic boundaries were optimized to obtain minimum extrusion power and to predict coating failure. From the models, the critical extrusion die angle can be derived. The analytical results agreed well with the results from the finite element simulation. The developed models can be used for extrusion die design and process analysis and can lead to lower cost and environmental friendly manufacturing technologies.

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