Nondestructive Evaluation (NDE) of Sintered Silicon Carbide and its Correlation to Microstructure and Mechanical Properties

摘要

High density is a critical acceptance criterion for armor ceramics. Quantifying the difference in density between what would be considered to be a 'good' or 'bad' region is complicated. As density is reduced from theoretical, does this infer the presence of defects. The minimum acceptable density that ensures favorable ballistic performance is unknown. This question concerns not only the presence of defective regions, which may include pores or inclusions, but also the spatial distribution of the defect within the sample. This study will seek to expand upon correlating the microstructural assessment, mechanical properties, and non-destructive evaluation results of ceramic armor tiles. This study will present the techniques necessary for microstructural analysis, which include nearest-neighbor distance distributions, tessellation analysis, average pore size, and pore size distributions. The ability of Knoop indentation and 4- pt flexure tests, combined with the results of ultrasound C-scans, to reliably predict ballistic performance of armor ceramics will be evaluated.