Effects of high pressure and high strain rate on dynamic compressive strength of alumina

Critical value which transforms from elastic deformation to inelastic deformation is corresponding with the compression strength of the material under the plane impact compression. Hydrostatic pressure and high strain-rate influenced material strength seriously. In this paper, we establish a non-elastic deformation of the dynamic yield condition based on the viscoplastic material law analogy, and introduce the Drucker-Prager static yield criterion to consider the effect of hydrostatic pressure and high strain-rate. We give a new representation of Hugoniot elastic limit. The shock compression experiments of alumina ceramics were carried out under 1D strain state one-stage gas gun and free surface velocity histories of particles in alumina were measured by VISAR. The experimental determination of the dynamic strength of alumina was discussed and open problems were clarified.