doi:10.3850/978-981-08-7619-7_P064

ABSTRACT

A two-dimensional flaw-driven, elastic material model for strain-rate dependent behavior of brittle materials with rectilinear flaws was created by Paliwal and Ramesh (2008). This model employs a crack growth law by Ashby and Hallam (1986) in a self-consistent framework that requires information about flaw density, flaw size distribution, and pristine material properties. In recent work by Graham-Brady (2010), a microstructure of clustered rectilinear flaws is generated via stochastic simulation, providing a basis for predicting spatial variation of strength. This work shows that the Weibull distribution, which is often used to determine the random material strength, does not accurately capture the predicted dynamic strength information for this material. In the current paper, a modified version of the model is used for circular flaws in two dimensions based on the crack growth law by Sammis and Ashby (1986). Applying a uniaxial compressive loading condition, the strength results for the rectilinear and circular flaw type models are compared when using different flaw size distributions. The simulated microstructure will again serve as a basis for identifying the microstructural sources of scatter in strength and the spatial variability of strength for different clustering parameters.

Keywords: Brittle materials, Ceramics, Compressive properties, Crack growth, Damage, Failure, Fracture, High strain, Impact, Modeling.

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