Deformation Heterogeneity in Cellular Al Alloys

Bastawros, Ashraf F.; Evans, A.G.

doi:10.1002/(sici)1527-2648(200004)2:4<210::aid-adem210>3.0.co;2-z

Cited by 31 publications

(16 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The plateau phase ends when all pores are compressed. The subsequent section is the compaction of the struts like a bulk material and is characterised by a steeply increasing stress [4][5][6]9,10]. Whereas bulk materials show a nearly similar material behaviour under compression and tension, metal foams offer a distinct compressive characteristic but only a very poor tensile strength.…”

Section: Introductionsupporting

confidence: 62%

Micro-structural motivated phenomenological modelling of metal foams: experiments and modelling

2014

View full text Add to dashboard Cite

Cellular materials like metal foams are bio-inspired materials which exhibit great potential for application in lightweight construction or as kinetic energy absorber. Such cellular materials show a complex micro-structure which significantly affects the macroscopic global properties. Cellular materials exhibit localised deformation expressed in deformation bands under inelastic strain conditions. Engineering with metal foams requires material models which describe the material behaviour properly even for different load cases. In this work, a new modelling approach has been developed which phenomenologically accounts for microstructural effects by a representative volume element made of several springs. The model is experimentally validated, and its micro-structural motivated parameters are experimentally identified in quasi-static compression tests with unloading cycles. Using digital image correlation, it was possible to connect the micro-structural deformation with the global macroscopic stress-strain behaviour, evaluated locally for the front surface of the specimens.

show abstract

Section: Introductionsupporting

confidence: 62%

Micro-structural motivated phenomenological modelling of metal foams: experiments and modelling

2014

View full text Add to dashboard Cite

show abstract

“…There is little experimental measurements of the Poisson's ratio reported in the literature and it Poisson's Ratio has often been assumed to be close to 0.35 for metallic foams. [1,[7][8][9] Figure 3 presents a typical compression curve showing the three deformation stages, the first linear regime preceded by the loading shoulder (1), the plastic deformation plateau (2) and the densification (3). The vertical lines on the curves represent the successive unloading done to monitor the evolution of the elastic modulus during the test.…”

Section: Laser-ultrasonic Resultsmentioning

confidence: 99%

“…[11] The deformation in the foam is not homogeneous and continuous and plastic deformations may be localized in some areas, as demonstrated by different researchers. [5,8] Thus, after plastic deformation, the elastic modulus is measured on heterogeneous foams having a distribution of densities.…”

Section: Methods Elastic Modulus (Gpa)mentioning

confidence: 99%

Elastic Response of Titanium Foams During Compression Tests and Using Laser‐Ultrasonic Probing

Lefebvre¹,

Blouin²,

Rochon³

et al. 2006

Adv Eng Mater

View full text Add to dashboard Cite

This paper presents an evaluation of the elastic properties of titanium foams by two methods: the evaluation of the unloading slopes measured during destructive compression tests and the measurements of the resonance frequencies of foams using laser‐ultrasonics. The results show that the elastic moduli evolve during the compression tests. The values extrapolated at zero deformation can be used to determine the elastic properties of undeformed specimens. Besides, laser‐ultrasonic techniques can be used to bring foam specimens into resonance and to measure the elastic modulus and Poisson's ratio. The values measured by the two methods are in good agreement.

show abstract

“…It is apparent that the visible macroscopic deformation is concentrated in one layer oriented perpendicular to the loading direction. This kind of deformation behavior has also been observed at ambient [11] and elevated [6] temperatures.…”

Section: Mechanical Characterizationmentioning

confidence: 99%

Creep of aluminum-based closed-cell foams

Haag,

Wanner,

Clemens

et al. 2003

Metall Mater Trans A

View full text Add to dashboard Cite

Metal foams creep when loaded mechanically at high homologous temperatures. We have studied the creep behavior of closed-cell aluminum-based foams with relative densities of 0.092, 0.112, and 0.163. Compressive creep tests were performed at 300°C at strain rates ranging from 10 Ϫ9 to 10 Ϫ4 s Ϫ1 . Special efforts were made to produce and characterize a bulk reference material exhibiting the same chemical composition. Results show that the foams exhibit a lower creep strength and a higher stress exponent than predicted by the Gibson-Ashby model for regular foams. The possible mechanisms responsible for this deviation are discussed. A semi-empirical rate equation is established which describes the experimental data well.

show abstract

Deformation Heterogeneity in Cellular Al Alloys

Cited by 31 publications

References 13 publications

Micro-structural motivated phenomenological modelling of metal foams: experiments and modelling

Micro-structural motivated phenomenological modelling of metal foams: experiments and modelling

Elastic Response of Titanium Foams During Compression Tests and Using Laser‐Ultrasonic Probing

Creep of aluminum-based closed-cell foams

Contact Info

Product

Resources

About