Vu Thanh Phuong^1,2, Steven Verstichel³, Patrizia Cinelli^1,4, Irene Anguillesi¹, Maria-Beatrice Coltelli¹, Andrea Lazzeri^1,*

Journal of Renewable Materials, Vol.2, No.1, pp. 35-41, 2014, DOI:10.7569/JRM.2013.634136

Abstract Cellulose acetate (CDA) cannot be processed as raw material because it starts to decompose before melting. Triacetin and diacetin were tested to improve CDA processing versus conventional phthalate as environmentally sustainable plasticizers, because of their low toxicity and fast biodegradability. The addition of triacetin and diacetin allowed melt processing of CDA and the results of tensile tests outlined their effect as plasticizers. The values of mechanical properties were compatible with the requirements for applications in rigid packaging. From the results of biodegradation tests it can be concluded that for pure cellulose acetate, complete biodegradation was More >

L. Poussard^1,*, A. Mecheri¹, J. Mariage¹, I. Barakat¹, L. Bonnaud¹, J.-M. Raquez^1,2, P. Dubois^1,2

Journal of Renewable Materials, Vol.2, No.1, pp. 13-22, 2014, DOI:10.7569/JRM.2013.634132

Abstract Biobased oligo(butylene succinate)-based thermoplastic polyurethanes (TPUs) were prepared following a twostep polymerization process: condensation of succinic acid and butanediol and the chain extension of resulting hydroxyl-terminated butylene succinate oligomers (OBS) in the presence of butanediol as chain extender and isophorone diisocyanate (IPDI) as coupling agent. Mechanical and thermal properties of the elaborated TPUs were evaluated in terms of hard segment and compared with those of commercial polybutylene succinate (PBS), Bionolle 1001. Whatever the compositions, the ultimate tensile properties of OBS-based TPUs and Bionolle 1001 were found to exhibit similar values (ε_r ≈ 400%, σ_r ≈ 40 More >

M. Tazi¹, F. Erchiqui^1,*, F.Godard¹, H. Kaddami²

Journal of Renewable Materials, Vol.2, No.4, pp. 258-263, 2014, DOI:10.7569/JRM.2014.634120

Abstract This article evaluates the mechanical properties and biodegradability of wood-plastic composite materials made from sawdust and thermoplastic polymer (HDPE). For the preparation of the composites, sawdust in different proportions with Maleic Anhydride grafted Polyethylene (MAPE) as the coupling agent was used. The mechanical properties and biodegradability of the biocomposites were successively characterized. The results indicate that adding sawdust particles to a polymer matrix improves the mechanical strength and stiffness of composites. The tensile strength of a composite with 3% coupling agent was improved by 13%, 34% and 54% respectively when 20%, 30% and 40% wood… More >

Amar Boukerrou^*, Dalila Hammiche, Djidjelli Hocine, Hassina Aouat

Journal of Renewable Materials, Vol.2, No.4, pp. 249-257, 2014, DOI:10.7569/JRM.2014.634119

Abstract The lack of compatibility between cellulose fi bers and some polymers, such as thermoplastics, is due on one hand to the hydrophilic nature of the vegetable fi bers and on the other hand to the hydrophobic character of the matrix. This incompatibility induces bad dispersion of the fi bers and the formation of a heterogeneous material with mechanical properties which are not very satisfactory. The scope of this article is to describe the possibility of using Olive Husk Flour (OHF) as reinforcement in the elaboration of a composite material based on polyvinyl chloride (PVC). In More >

Y. Zhang¹, Y. F. Nie², Y. T. Wu¹

CMC-Computers, Materials & Continua, Vol.40, No.3, pp. 203-218, 2014, DOI:10.3970/cmc.2014.040.203

Abstract The present study aims to evaluate the mechanical properties of steel fiber reinforced concrete (SFRC) by the statistical second-order two-scale (SSOTS) method. At first, the representation for microstructure of SFRC is described by a concept of statistical screen. According to the microstructure representation, the SSOTS method is displayed in a concise way. This method is on the basis of asymptotic expansion homogenization and Monte Carlo method, and can calculate the local strain and stress field through the two-order displacement solution. As the classical homogenization method, the expression of homogenized elastic modulus is derived analytically. Then More >

Zihao Yang¹, Junzhi Cui², Yufeng Nie¹, Yatao Wu¹, Bin Yang³, Bo Wu⁴

CMC-Computers, Materials & Continua, Vol.38, No.3, pp. 175-194, 2013, DOI:10.3970/cmc.2013.038.175

Abstract This study is concerned with the microstructural modeling and mechanical properties computation of three-dimensional (3D) 4-directional braided composites. Microstructure of the braided composite determines its mechanical properties and a precise geometry modeling of the composite is essential to predict the material properties. On the basis of microscopic observation, a new parameterized microstructural unit cell model is established in this paper. And this model truly simulates the microstructure of the braided composites. Furthermore, the mathematical relationships among the structural parameters, including the braiding angle, fiber volume fraction and braiding bitch, are derived. By using the unit More >

J. Joseph¹, Y. C. Lu¹

CMC-Computers, Materials & Continua, Vol.37, No.1, pp. 59-75, 2013, DOI:10.3970/cmc.2013.037.059

Abstract The aligned carbon nanotube (A-CNT) structure is composed of arrays of individual CNTs grown vertically on a flat substrate. The overall structure and properties of an A-CNTs are highly dependent upon the designs of various architectures and geometric parameters. In Part 2, we have presented the detailed designs and modeling of various aligned carbon nanotube structures. It is found the A-CNT structures generally have much lower modulus than an individual CNT. The reason is due to the high porosity and low density of the A-CNT structures, since the interstitial space between nanotubes is mostly occupied More >

K.N. Song¹

Structural Durability & Health Monitoring, Vol.8, No.3, pp. 209-222, 2012, DOI:10.32604/sdhm.2012.008.209

Abstract A PHE (Process Heat Exchanger) is a key component in transferring the high temperature heat generated from a VHTR (Very High Temperature Reactor) to the chemical reaction for the massive production of hydrogen. A performance test on a small-scale PHE prototype made of Hastelloy-X is currently under way a small-scale gas loop at the Korea Atomic Energy Research Institute. Previous research on the elastic high-temperature structural analysis of the small-scale PHE prototype has been performed using the parent material properties over the whole region. In this study, an elastic-plastic high-temperature structural analysis considering the mechanical More >

Igor Grešovnik^1,2, Tadej Kodelja¹, Robert Vertnik^2,3, Bojan Senčič^3,2,3, Božidar Šarler^1,2,4

CMC-Computers, Materials & Continua, Vol.30, No.1, pp. 19-38, 2012, DOI:10.3970/cmc.2012.030.019

Abstract Artificial neural networks (ANNs) are employed as an alternative to physical modeling for calculation of the relations between the production path process parameters (melting of scrap steel and alloying, continuous casting, hydrogen removal, reheating, rolling, and cooling on a cooling bed) and the final product mechanical properties (elongation, tensile strength, yield stress, hardness after rolling, necking) of steel semi products. They provide a much faster technique of response evaluation complementary to physical modeling. The Štore Steel company process path for production of steel bars is used as an example for demonstrating the approach. The applied… More >

MC. Ho Ba Tho¹, PE Mazeran², K El Kirat¹, S.F. Bensamoun¹

CMES-Computer Modeling in Engineering & Sciences, Vol.87, No.6, pp. 557-578, 2012, DOI:10.3970/cmes.2012.087.557

Abstract Mechanical properties of cortical human bone have been investigated for more than four decades. Numerous experimental investigations on bone characterization were performed ; mechanical, vibrational, acoustical testing and morphological, physico-chemical investigations. Due to the techniques, different levels of investigation were performed and subsequently quantitative parameters are concerning different level of structure of bone (organ, tissue,... ). According to our knowledge, few investigations were performed simultaneously on mechanical, morphological and physico-chemical properties of bone. The objectives of the present study were to investigate the influence of multiscale structural characteristics of the bone tissue on its mechanical More >