Naslov
DEFORMATION AND FAILURE MECHANISMS OF ALUMINIUM FOAMS USING REJECTED PRECURSOR MATERIALS

Autori
Duarte, Isabel ; Vesenjak, Matej ; Krstulović-Opara, Lovre

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Proceedings of the First National Conference of Cellular Materials MATCEL 2015 / Duarte, Isabel ; Valente, Robertt ; Andrade-Campos, António - Aveiro : University of Aveiro, 2015, 41-41

ISBN
978-972-99784-3-2

Skup
First National Conference of Cellular Materials MATCEL 2015

Mjesto i datum
Aveiro, Portugal, 07.09.2015. - 08.09.2015

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
Aluminium foams; Uniaxial compression behaviour; Deformation mechanisms

Sažetak
The powder metallurgy is an eco-efficient process to produce metal foams. Simple or complex near net shape parts of aluminium foams with considerable large dimensions can be obtained using rejected precursor pieces from the cutting in the intermediate stage, which is usually the step used to cut the single precursors from large panels. The obtained foam products result from a rather ecoefficient process where the rejected sub-systems enable the formation of an integral-skin foam with quite interesting global properties. The work aims to study the deformation and failure mechanisms of rectangular foam blocks prepared from rejected precursors using uniaxial compressive tests under dynamic loading conditions supported by middle-wave infrared thermography. The dynamic compressive behaviour of these foams was compared to the behaviour of the foam blocks prepared from a traditional single precursor. The results show that the foams from rejected precursors begin to deform at lower strain showing local deformation dispersed at the surface foams leading to the formation of many deformation bands, while the reference ones (with a single precursor) present few deformation bands mainly located at its lower and upper ends. The bands occur at the weakest points of the samples, which in case of the samples made of rejected precursors correspond to the joining regions formed within the foam by the different precursors used during the foaming process. In these joining regions imperfections and structural defects are developed like micro-pores promoting a stress concentration where the cracks initiate. The results also indicate that the plateau region of the compressive stress-strain curves (the stress gradually increases with increasing strain) is much more inclined in case of the foams from rejected precursor pieces compared to the reference ones.

Izvorni jezik
Engleski

Znanstvena područja
Strojarstvo

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