Porous ceramics, or cellular ceramics, are comprised of a heat-resistant porous material with many gaseous pores. Porous ceramics began developing in the 1970s and are generally divided into honeycomb ceramic and ceramic foam. They have relatively high levels of mechanical strength, corrosion resistance, stability under high temperatures, high thermal conductivity, waterproof nature, and durability. Porous ceramics perform well in terms of filtration and adsorption and can be used in many fields, including metallurgy, chemical engineering, environment protection, energy, and biology. Applications include elevated temperature filters, thermal gas separation, lightweight structural components, and thermal structural materials. Numerous fabricating methods are implemented to produce highly porous ceramics and micro-CT is an important tool for nondestructive evaluation and quantification of their microstructures.

Permeability of porous ceramics by X-ray CT image analysis
This work presents a method to characterize the complex geometry of porous material microstructures and relate these metrics to material properties such as permeability. Porous synthetic cordierite and aluminum titanate materials are studied, using micro-CT images of the porous microstructure. “Direct simulations of the microstructures were made to estimate effective permeability and correlations are presented to microstructural metrics. High quality relationships are established, specifically utilizing 2-point correlation functions and linear path function characteristic dimensions. Results are compared to legacy methods such as the widely known relationships proposed by Kozeny-Carman and Kuwabara.”
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Characterization of the morphology of cellular ceramics by 3D image processing of X-ray tomography
The benefits of Micro-CT for the study of porous ceramics is demonstrated in this non-destructive study of the X-ray tomography images of various cellular ceramics. “The samples demonstrated a wide range of cell sizes (m to mm) with a narrow range of porous fraction (75–85 vol.%)”. Using 3D mathematical morphological operation on the images, the thickness distribution of pores and ceramics was established. A comparison to optical and electron microscopy granulometry measurements was then made.
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Micro-CT studies on 3-D bioactive glass-ceramic scaffolds for bone regeneration
Progress in chemical, physical, material and biological sciences has brought about the possibility of bone tissue engineering, providing a biologically-based method for repair and regeneration of natural tissues. The scaffold is a key component in tissue engineering for bone regeneration, acting as a “template for cell interactions and for the growth of bone-extracellular matrix to provide structural support to the newly formed tissue”. Ceramic scaffolds require a macroporosity of 100–500 μm to promote bone cell attachment, and a microporosity of less than 10 μm to enable ion and liquid diffusion. This study of the characterization of bioactive glass-ceramic scaffolds for bone tissue engineering describes the preparation to obtain “scaffolds possessing an open and interconnected porosity, analogous to cancellous bone texture, and with a mechanical strength above 2 MPa”.
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Micro-CT – a digital 3D microstructural voyage into scaffolds: a systematic review of the reported methods and results
This review highlights the relationship between scaffold microstructure and cell behavior. It provides the basics of utilitizing micro-CT to analyze, visualize, and explore any portion of interest in the scaffold in 3D fashion, nondestructively with little or no sample preparation. The key to tissue regeneration is cell behavior, and most cells used in tissue engineering are anchorage-dependent. Thus, adhesion, growth, migration, matrix synthesis, and differentiation is key to the design of the scaffolds. Micro-CT provides a powerful platform for the characterization of the scaffolds.
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