Experimentally measured mechanical properties of hollow sphere steel foam are the subject of this paper. The characterization of the hollow sphere foam encompasses compressive yield stress and densification strain, compressive plastic Poisson’s ratio, and compressive unloading modulus, as well as tensile elastic modulus, tensile unloading modulus, tensile yield stress, and tensile fracture strain. Shear properties are also included. These tests provide sufficient information to allow calibration of a macroscopic, continuum constitutive model. Calibrated foam plasticity parameters are tabulated, and unique feature of foam plasticity are explained. Also, initial development of mesoscale simulations, which explicitly model voids and sintered hollow spheres, is reported. This work is part of a larger effort to help the development of steel foam as a material with relevance to civil engineering applications.
Kari, S.; Berger, H.; Rodriguez-Ramos, R.; Gabbert, U. Computational evaluation of effective material properties of composites reinforced by randomly distributed spherical particles. Compos. Struct. 2007, 77, 223–231, doi:10.1016/j.compstruct.2005.07.003.
[3]
Gao, Z.Y.; Yu, T.Z.; Karagiozova, D. Finite element simulations on the mechanical properties of MHS materials. Acta Mech. Sin. 2007, 23, 65–75.
[4]
Gibson, L.J.; Ashby, M.F.; Ashby, M. Cellular Solids: Structure and Properties, 2nd ed.; Cambridge University Press: Cambridge, UK, 1999.
[5]
Friedl, O.; Motz, C.; Peterlik, H.; Puchegger, S.; Reger, N.; Pippan, R. Experimental investigation of mechanical properties of metallic hollow sphere structures. Metall. Mater. Trans. B 2008, 39, 135–146.
[6]
Ashby, M. Metal Foams？: A Design Guide; Butterworth-Heinemann: Boston, MA, USA, 2000.
[7]
Gao, Z.Y.; Yu, T.X.; Zhao, H. Mechanical behavior of metallic hollow sphere materials: Experimental study. J. Aerosp. Eng. 2008, 21, 206–216, doi:10.1061/(ASCE)0893-1321(2008)21:4(206).
[8]
Wouterse, A.; Philipse, A.P. Geometrical cluster ensemble analysis of random sphere packings. J. Chem. Phys. 2006, 125, 194709:1–194709:10.
[9]
Kansal, A.R.; Torquato, S.; Stillinger, F.H. Computer generation of dense polydisperse sphere packings. J. Chem. Phys. 2002, 117, 8212–8218, doi:10.1063/1.1511510.
[10]
Andrews, E.; Gioux, G.; Onck, P.; Gibson, L. Size effects in ductile cellular solids. Part II: Experimental results. Int. J. Mech. Sci. 2001, 43, 701–713, doi:10.1016/S0020-7403(00)00043-6.
[11]
Khan, A. Continuum Theory of Plasticity; Wiley: New York, NY, USA, 1995.
[12]
Miller, R.E. A continuum plasticity model for the constitutive and indentation behaviour of foamed metals. Int. J. Mech. Sci. 2000, 42, 729–754, doi:10.1016/S0020-7403(99)00021-1.
[13]
Deshpande, V.S.; Fleck, N.A. Isotropic constitutive models for metallic foams. J. Mech. Phys. Solids 2000, 48, 1253–1283, doi:10.1016/S0022-5096(99)00082-4.
[14]
Hanssen, A.G.; Hopperstad, O.S.; Langseth, M.; Ilstad, H. Validation of constitutive models applicable to aluminium foams. Int. J. Mech. Sci. 2002, 44, 359–406, doi:10.1016/S0020-7403(01)00091-1.
[15]
Reyes, A.; Hopperstad, O.S.; Berstad, T.; Hanssen, A.G.; Langseth, M. Constitutive modeling of aluminum foam including fracture and statistical variation of density. Eur. J. Mech. A Solids 2003, 22, 815–835, doi:10.1016/j.euromechsol.2003.08.001.
