Energy dissipation mechanism of ceramic matrix composites during the process of dwell

Ceramic matrix composites behave excellent ballistic performance in dwell process. With the purpose of increasing application value and revealing the ballistic mechanism of composites, it is necessary to investigate energy dissipation mechanism during the process of dwell. In this paper, the dwell process of SiC-Al ceramic matrix composites was studied by utilizing micro numerical simulation method. Micro and macro structure characteristics of composite are employed to analysis the behavior of ceramic phase and metal phase comparatively. The effect of composite microstructure on stress wave propagation is also investigated. It was concluded that the internal energy of ceramic phase or metal phase accounts for different proportion in the three different stages of dwell process. Ceramic and metal behave distinct performances. Crack initials and propagates in ceramic at the beginning till it encounters the metal. The plastic deformation of metal can prevent crack propagation effectively or change the crack propagation path, and also can create hydrostatic stress around the ceramic phase to enhance the full damaged strength, Resulting that the composite can bear higher strain and maintain intact to extend the dwell time. In addition, the interface between ceramics and metals can disperse and weaken the stress wave to reduce the energy.