MicroStructural Hierarchy Descriptor (μSHD)–property correlations of silicon carbide ceramics

Abstract

A systematic and extensible framework for quantification of structural hierarchy is indispensable to understand the structure–property correlation of SiC ceramics. Microstructural hierarchy descriptor (μSHD) is constructed and used to quantify experimental microstructures reported in the literature. Despite a variation nature of microstructures and the scatterness in measured properties, μSHD–property correlations have been identified. The μSHD curves with less hierarchical levels suggest a high strength, while more hierarchical levels are related to a high toughness. The μSHD curve exhibiting a homogeneous distribution across all the scales and one exhibiting a gradual decrease from the smaller to larger scales can both stand for a high thermal conductivity. A quick drop from the smaller to larger scales on the μSHD curve is a characteristic of a high electrical resistivity, and a reverse trend, showing a gradual increase from smaller to larger scales and maintaining larger μSHDs at larger scales, characterizes a low resistivity.