Effect of Grain Size, Second Phases and Texture in the Dynamic Failure of Ceramics

9523113埃斯皮诺萨拟议的研究采用实验和理论相结合的方法，使用冲击载荷来研究微观结构特征对陶瓷失效的影响。该实验方法使用了新颖的平板和冲击实验，其中可以选择应力脉冲的大小和持续时间，以便损伤事件是稳定的，并且可以在明确的变形历史下监测其演化。因此，可以识别损伤演化而不是最终累积损伤。这些结果将为全面理解非弹性变形过程和建立基于物理的本构方程奠定基础。干涉测量测得的速度历史将用于已建立的模型的检验。测量的速度历史和数值计算的速度历史之间的关联将通过使用非弹性模型进行实验的数值模拟来实现，该模型解释了观察到的破坏机制。***

9523113 Espinosa The proposed research deals with a combined experimental and theoretical approach using impact loading to study the influence of microstructural features on failure of ceramics. The experimental approach uses novel plate and impact experiments where the magnitude and duration of stress pulses can be selected so that the damage event is stable and its evolution can be monitored under well defined deformation histories. As a result, damage evolution rather than final accumulated damage can be identified. These results will form the basis for comprehensive understanding of the processes occurring during inelastic deformation and formulation of physically based constitutive equations. Interferometrically measured velocity histories will be used in the examination of formulated models. Correlation between measured and numerically computed velocity histories will be accomplished by performing numerical simulations of the experiments with inelastic models accounting for the observed failure mechanisms. ***