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This paper proposes the new methodology for geometrical properties identification of step-wise deformed closed-cell aluminum alloy foam. The change of internal structure of cylindrical foam specimens during deformation is ex situ recorded by a micro computed tomography scanner. The geometry of five specimens is analyzed in un-deformed and several deformed states until 70% of engineering strain. The obtained CT images is used to construct the 3D computer models of un-deformed/deformed foam specimens. These are then subjected to an automated analysis of the geometrical properties of internal structure to determine the size, distribution, and orientation of the pores. The results provide the basis for further analysis of the variation in internal structure during the deformation process. The internal structure of un-deformed specimens exhibits a pore orientation dependent on the fabrication process. Significant changes of internal pore structure is observed during the deformation process, where the specimens with small spatial variation of porosity sustains larger strains until failure under compressive load. The specimens with larger spatial variation of porosity and larger pore concentrations disintegrate earlier.

A heavy-reduction controlled rolling process with approximately 75% thickness reduction was carried out to investigate the microstructural evolution including texture development, focusing on the formation of a bimodal structure of 0.2% carbon steel with heating temperatures of 700, 800, 900, and 1000 o C. Upon increasing the heating temperature from 700 to 900 o C, the microstructure was refined and precipitates such as Fe 3 C were uniformly distributed throughout the microstructure. For the microstructures control-rolled at heating temperatures of 900 and 1000 o C with average ferrite grain sizes of 1.34 and 1.63 µm, respectively, a bimodal structure

The mechanical properties of Advanced Pore Morphology (APM) foam elements depend strongly upon their internal porous and external structural geometry. This paper reports on a detailed investigation of external (e.g. shape and size) and internal (e.g. distribution, size, number of pores) geometry and porosity changes of APM foam elements, during compressive loading by means of the ex-situ micro-Computed Tomography, and advanced digital image analysis and recognition. The results show that the porosity of APM foam elements decreases by only 25% at the engineering strain of 70% due to an increase of the number of pores at high stages of compressive deformation. The APM foam elements also exhibit a positive macroscopic Poisson’s ratio of υ = 0.2, which is uncharacteristic for cellular structures.