Imaging of metallic foams using X-ray micro-CT

Physical properties of metallic foams are a direct consequence of their micro-/macro-structure. To improve these materials, it is necessary to understand exactly how the microstructure determines these properties. In this study we consider a range of metallic foams that have been prepared under various conditions. The metal foams are made of Al alloys and Zn and were produced by adding different amount of blowing agents. Additionally, external gas pressure was applied during foaming process. These samples were then imaged in 3D using X-ray CT. Advanced 3D image analysis were carried out on the samples to extract geometrical and topological properties of the cells and also the solid phase. As a result, pore (cells) size distribution and solid fraction (relative density) are directly measured on the images. We characterise cell shape and size and attempt to correlate them with the manufacturing parameters.

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