Digital Image Correlation technique applied to mechanical characterisation of aluminium foam

Abstract

In this paper the possibility to employ the Digital Image Correlation (DIC) technique for the mechanical behaviour analysis of metallic foam was investigated. Image Correlation allowed to measure displacement and strain fields on closed and open cells aluminium foam specimens under two different loading conditions (compression and shear) and to characterise, with opportune calculation, information on the mechanical behaviour of foams. The adopted technique is suitable to conduct a deep analysis and also to appreciate the local heterogeneities that appear in a specimen during test. The parameters obtained with DIC analysis are confirmed by the global data obtained by testing machine proving the adopted methodology represents a valid tool for the study of these new materials.

Fatigue behaviour of aluminium foam sandwiches

“…Although the observed failure mode is generally governed by shear stress, the best stress parameters that have been identified to describe the fatigue behaviour is the normal stress in the foam or in the skin. It seems in fact that the normal stress gives a better description of the global stress state of the foam sandwich even if the failure seems to be dominated by shear stress.…”

“…Shear stress, which is higher near the laminate middle line, induces little microfractures randomly oriented caused by material inhomogeneity . The number and dimension of microfractures increase until a complete horizontal crack formation.…”

“…Final breaking, which also interests external skins, can take place in several ways, and it is conditioned by shear force entity: for thicknesses lower than 20 mm, a plastic skin yielding (Fig. (a)) or more rarely the skin breaking (Fig.…”

Assessing the influence of four cutting methods on the thermal contact resistance of open-cell aluminum foam

“…[34] used a circular sawing (CS) machine to prepare samples for an investigation of shear deformation. To study a metallic bonding of aluminum foam on a substrate, [35] prepared the foam surface with thin silicon-carbide (SiC) blades.…”

Surface structure, pore characteristics and mechanical response of aluminum foam processed by wire-EDM and milling

“…Several manufacturing processes were proposed in literature for porous metals, such as milling, circular saw cutting, water jet cutting, plasma, laser etc. [4][5][6][7][8]. The Wire Electrical Discharge Machining (wEDM) is the machining process during which material is eroded by series of controlled sparks between electrode and the workpiece.…”