Stress distribution and interfacial debonding process at the interface between a rubber mold and a powder compact were analyzed during unloading under cold isostatic pressing. The proposed Cap model was used for densification behavior of powder, based on the yield function of a general Cap model and volumetric strain evolution. The increased adhesion force at the interface under cold isostatic pressing may have influence on stress distribution and crack in a powder compact, and deformation of a rubber mold during unloading. Cohesive elements incorporating a bilinear cohesive zone model were used to study debonding process at the interface having interfacial strength under cold isostatic pressing. The residual stress in the rubber mold at the perfect bonding interface was investigated under various hydrostatic stresses during unloading. By using the cohesive zone model, the maximum principal stress in a powder compact was calculated for several interfacial strengths at the interface during unloading. The variations of the stored elastic energy density in a rubber mold were also investigated during interface debonding process.
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