The numerical modeling of the Hot Isostatic Pressing requires the complete identification of the constitutive equations describing the powder behavior during densification. The rheological functions parameters of the constitutive equation are determined by tests. Experiments such as Hot Isostatic Pressing and uniaxial compression are sufficient to determine the two parameters of the models currently used (ABOUAF, CASSENTI).In some cases, these models are insufficient. Some authors (STUTZ) suggest a three parameter law which identification requires an additional test such as Hot Die Pressing: the stress measurement enables to complete our information about the rheological behaviour of the powder. An experimental device has been perfected to measure radial and axial stress at high temperature. Radial stress is deduced by deformation measurement of the die heated by induction. The calibration relation between stress and deformation is obtained by modelling the die behavior and by experimental tests. The test protocol as well as the first results obtained on titanium powder are presented and commented on.
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