The compaction behavior of a granulated powder of nanocrystalline 3 mol% yttria-stabilized tetragonal ZrO2 polycrystals (3Y-TZP) was investigated by cold isostatic pressing. An elastomer gel was used as the solid pressure medium to form the compacts, in a process referred to as elastomer gel-cold isostatic pressing (E-CIP). The relative density (D-re) of the compact produced by isostatic pressing at a pressure (P) of 1522 MPa is 0.617, which is close to the upper limit of random packing (0.63). A curve fitted to the In [1/(1-D-re)] vs P-1/2 plot shows two linear regions, with a point of intersection at a transition pressure (P-c) of 520 MPa. A coral-like morphology of approximately spherical aggregates remains unchanged in E-CIP compacts formed at below the P-c Many isolated aggregates are observed in E-CIP compacts formed at above the P-c. Thus, the transition in the fitting curve indicates the destruction of strong bonds between aggregates. (C) 2018 Elsevier B.V. All rights reserved.