Mechanical and Numerical Analysis Concerning Compressive Properties of Tin-Lead Open-Cell Foams

Abstract

International audienceThe design of new or innovative materials has to meet two essential criteria: increased mechanical performance and minimization of the mass. This dual requirement leads to interest in the study of various classes of metallic foams. The actual research is focused on open-cell Tin-Lead foams manufactured by replication process using NaCl preform. A mechanical press equipped with a load cell and a local extensometer with a controlled deformation rate is used. Experimental tests were carried out in order to study the influences of both the cell size and of the relative density on the mechanical behavior during a compression deformation and to analyze the obtained properties variation within a new framework. This study has three main sections which start with the manufacturing description and mechanical characterization of the proposed metallic foams followed by the understanding and modeling of their response to a compression load via a Gibson-Ashby model, a Féret law, a proposed simple Avrami model, and a generalized Avrami model. Finally, an exposition of a numerical simulation analyzing the compression of the Sn-Pb foams concerning the variation of the relative densities with respect to the plastic strain is propose

Elaboration and Mechanical-Electrochemical Characterisation of Open Cell Antimonial-lead Foams Made by the “Excess Salt Replication Method” for Eventual Applications in Lead-acid Batteries Manufacturing

“…7a, had the same mechanical behaviour as all other open cell replicated foams as those described in refs. 14,28,29 The graphs clearly depict three distinct regions of deformation. The first one is a linear elastic region, where the stress rises linearly with increasing strain, in turn controlled by the elastic flexion of both the edges and walls of the cells.…”

“…The third region, when all cells are crushed, gives rapid increase of the stress, the so-called "densification region". 14 Note that plateau stress of SbS25 and SbS30 is: smooth, close, and the longest; while their porosities are completely different and their cell sizes are closed. The same remarks can be found for the couple of SbS35/SbS40 and SbS45/SbS50.…”

“…Gavrus et al 14 concerning the description of plateau-stress -relative density variation for metallic open cell foams, new physically-based relationships, proposed by authors, will be taken into account to describe the complete densification, corresponding to the compressive large plastic deformations.…”

Preparation and characterization of paraffin/nickel foam composites as neutron-shielding materials

“…The stress–strain curves can be divided into three regions, namely the initial linear elasticity, plateau and densification regions. 23,25,26 All the specimens appeared to undergo the initial linear elasticity region of their stress–strain curves. 21 Just after the elastic region, most of the curves show fluctuation in stress, the fluctuation of stress–strain curves represent localized crush and deformation spread to the rest of specimen as the compression test progressed.…”

“…21,25 The curves of composite samples show different shape in this regions, because of the heterogeneity of the composites. 26

Figure 7.Compression tests on 12 PPI nickel foams with and without the different fillers.

Figure 8.Compression tests on 6 PPI nickel foams with and without the different fillers.

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