M. Kirpluks^1*, U. Cabulis¹, A. Ivdre¹, M. Kuranska², M. Zieleniewska³, M. Auguscik³

Journal of Renewable Materials, Vol.4, No.1, pp. 86-100, 2016, DOI:10.7569/JRM.2015.634132

Abstract The most common sustainable solution for polyurethane (PU) materials is their production using renewable resources. Polyols derived from biomass and recycled polymers are the most promising way to do that. This study compares five different sustainable polyols as a possible raw material for production of highdensity rigid PU foams for automotive application. The goal of our study was to show that biobased polyols are a suitable replacement for polyols derived from petrochemical products. The influence of the chemical structure of polyols on the PU polymer matrix and foam properties was investigated. Two sources of PU raw material feedstock were studied:… More >

Aleksander Prociak^*, Elźbieta Malewska, Szymon Bąk

Journal of Renewable Materials, Vol.4, No.1, pp. 78-85, 2016, DOI:10.7569/JRM.2015.634129

Abstract In this article, the results of the foaming process analysis of fl exible polyurethane with different isocyanate indexes are presented. Two types of flexible polyurethane foams (FPURF) were obtained: (1) by using petrochemical components and a rapeseed-oil-based polyol (used in the amount of 20 wt%), (2) by using petrochemical components and cellulose as a natural fi ller in the amount of 3 php (per hundred parts of polyol). The characteristic parameters of the foaming process, such as the foam’s growth velocity, the core temperature and dielectric polarization, were measured using a Foamat device. Moreover, the following properties of flexible polyurethane… More >

H.H. Luo¹, Z.H. Tan^1,2, X. Han¹, C. Chen¹

CMC-Computers, Materials & Continua, Vol.32, No.1, pp. 1-14, 2012, DOI:10.3970/cmc.2012.032.001

Abstract The dynamic properties of aluminium alloy foam were investigated by using split Hopkinson pressure bar (SHPB) with diameter of 40 mm. The aluminium alloy pressure bar and pulse shape technique were used to modify the traditional SHPB due to the low impedance of aluminium alloy foam. Wave dispersion correction on the aluminium alloy pressure bar was studied by Fourier series. And the finite element numerical simulation was also performed to demonstrate and validate the dispersion correction results by Fourier series method. The reflected and transmitted wave measured in SHPB experiments were corrected by the backward Fourier series expansion. The results… More >

Ligia Munteanu¹, Cornel Brisan², Veturia Chiroiu³, Stefania Donescu⁴

CMC-Computers, Materials & Continua, Vol.31, No.2, pp. 127-146, 2012, DOI:10.3970/cmc.2012.031.127

Abstract A modeling of the compression by using the property of Helmholtz equation to be invariant under geometric transformations is presented in this paper. The versatility of the geometric transformations is illustrated in order to obtain a new interpretation of the compression process. The physical spatial compression leads, most of the times, to new materials with inhomogeneous and anisotropic properties. The compression can be theoretically controlled by the geometric transformations. As an example, new architectures for auxetic materials can be built up by applying the geometric transformations. The new versions are finding their full correspondents in the results of the experiments… More >

Raghvendra Khedle¹, D.P.Mondal², S.N.Verma¹, Sanjay Panthi²

CMC-Computers, Materials & Continua, Vol.27, No.3, pp. 211-230, 2012, DOI:10.3970/cmc.2011.027.211

Abstract The interface in aluminum cenosphere syntactic foam (ACSF) is modeled using FEM to study its deformation behaviour as a function of interface characteristics such as interface stiffness and thickness. The interface is modeled as a thin layer of object. The effective modulus and stress of ACSF examined when it contain 50% cenosphere by volume. In this study, the shell wall thickness of cenosphere is fixed at 1µm. The width of the interface varies from 0.2% to 0.6% of cenosphere volume fraction. The interface strength and modulus varies in the range of 10 to 50% of the matrix alloy. The values… More >

Jin Ma¹, Jay C. Hanan¹, Ranga Komanduri¹, Hongbing Lu²

CMES-Computer Modeling in Engineering & Sciences, Vol.86, No.4, pp. 349-384, 2012, DOI:10.3970/cmes.2012.086.349

Abstract Amorphous metallic foams are an exciting class of materials for an array of high impact absorption applications, the mechanical behavior of which is only beginning to be characterized. To determine mechanical properties, guide processing, and engineer the microstructure for impact absorption, simulation of the mechanical properties is necessary as experimental determination alone can be expensive and time consuming. In this investigation, the material point method (MPM) with C1 continuous shape function is used to simulate the response of a bulk metallic glass (BMG) closed-cell foam (Pd42.5Cu30Ni7.5P20) under compression. The BMG foam was also tested experimentally under compression for validation of… More >

Weiwei Gong, Yan Liu, Xiong Zhang, Honglei Ma

CMES-Computer Modeling in Engineering & Sciences, Vol.83, No.5, pp. 527-546, 2012, DOI:10.3970/cmes.2012.083.527

Abstract Owing to its low density and good energy absorption capability, aluminum foam is an excellent protective material for spacecraft against debris impact. However, because of its complicated microstructure, it is very difficult to generate a FEM mesh accounting for the real microstructure of the alluminum foam. On the contrary, it is very easy to model three-dimensional problems with very complicated geometry with meshfree/meshless methods. Furthermore, the material point method has obvious advantages in modeling problems involving extreme large deformation problems like hypervelocity impact problem. In this paper, a three-dimensional material point model accounting for the real microsctructure of aluminum foam… More >

Weiwei Gong¹, Xiong Zhang^1,2, Xinming Qiu¹

CMES-Computer Modeling in Engineering & Sciences, Vol.82, No.3&4, pp. 195-214, 2011, DOI:10.32604/cmes.2011.082.195

Abstract Due to its high strength, low weight and strong anti impact capability, aluminum foam has great potential in the fields of transportation, aerospace and building structures as energy absorbing materials. Due to its complicated microstructures, it is desirable to develop an efficient numerical method to study the dynamic response of the aluminum foam under impact loading. In this paper, the material point method (MPM) is extended to the numerical simulation of the dynamic response of the aluminum foam under impact loading by incorporating the Deshpande Fleck's model and a volumetric strain failure model into our three-dimensional explicit material point method… More >

B. Madani¹, F. Topin², L. Tadrist²

FDMP-Fluid Dynamics & Materials Processing, Vol.6, No.4, pp. 351-368, 2010, DOI:10.3970/fdmp.2010.006.351

Abstract The present work deals with the hydraulic characterization of two-phase flow with phase change in a channel filled with metallic foam. We provide a general presentation of metallic foams including morphological characteristics, fabrication processes and industrial applications. The experimental facility, which consists of a hydrodynamic loop, the test section, measurement devices, and the data acquisition system, is presented. The Metallic foam sample tested in the present work is manufactured by SCPS (French manufacturer). N-pentane is used as a coolant fluid. The mass velocity values lie between 4 and 49 kg/ m2s, while the heating power in the test section ranges… More >

H. Altenbach¹, V. A. Eremeyev²

CMC-Computers, Materials & Continua, Vol.9, No.2, pp. 153-178, 2009, DOI:10.3970/cmc.2009.009.153

Abstract Within the framework of the direct approach to the plate theory we consider natural oscillations of plates made of functionally graded materials taking into account both the rotatory inertia and the transverse shear stiffness. It is shown that in some cases the results based on the direct approach differ significantly from the classical estimates. The reason for this is the non-classical computation of the transverse shear stiffness. More >