RHEOLOGY OF POWDER AND POROUS MEDIA IN MODELING OF PENETRATION INTO POROUS CERAMIC

摘要

In this paper, the concepts of mechanics of porous and powder media are applied for development of new analytical model of expansion of spherical cavity in porous brittle materials (ceramics). The model is based on the approach that recognizes the existence of three regions with different rheology: region of comminuted and compacted material; region of pore formation formed by radial cracks; elastically deformed region. Strain-stress state in each region is determined and analyzed. Condition of absence of pore formation region is specified. Cavity expansion pressure is determined. Energy losses on elastic deformation, fracture and compaction (non-elastic deformation) of material are calculated and compared for a number of materials. Penetration depth and target resistance depending on porosity is determined.