A research program was conducted to characterize the grain size distribution and shape characteristics of indigenous, discontinuous SiC and Al2O3 materials as possible ceramic reinforcements for PCMMCs. The results from automatic image analysis prove that a simple aspect ratio (maximum to minimum size ratio) is not able to completely define the required morphology of reinforcements, ranging in size between 1 and 10 mm. More complex shape factors were introduced with additional effect determined on three geometrical features of the particle: surface area, perimeter and maximal dimension. Alumina (Al2O3) with higher roundness shape factors appears to be beneficial especially for the applications where ductility is an important requirement.

 

 

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