A modified Drucker–Prager Cap model for finite element simulation of doped tungsten powder compaction

Abstract This paper presents a density dependent modified Drucker–Prager Cap (DPC) model for the compaction behavior of potassium doped tungsten powder. The experimental calibration of the model is done using an instrumented cylindrical die in powder compaction tests. The die is designed for direct determination of loading and unloading forces of powder compact inside the die in compaction and transverse directions. The cap surface parameters are characterized by fitting stress and strain curves acquired during loading to different green density values. The material parameters for the DPC failure surface are obtained by subsequent diametrical and axial compression tests. Additionally the contact pressure dependent wall friction coefficient is determined. The material model is implemented in the ABAQUS finite element code by user subroutines. The calculated compaction forces for a double-action compaction process are in excellent agreement with experimental data. The results show, that the proposed material model for doped tungsten can be used in finite element simulations of the compaction process.