Kuan-Ting Liu¹, Chun-Lin Lu¹, Nyan-Hwa Tai², Meng-Kao Yeh^{1, *}

CMES-Computer Modeling in Engineering & Sciences, Vol.122, No.2, pp. 661-674, 2020, DOI:10.32604/cmes.2020.07792 - 01 February 2020

Abstract In this study, the deformation and stress distribution of printed circuit board (PCB) with different thickness and composite materials under a shock loading were analyzed by the finite element analysis. The standard 8-layer PCB subjected to a shock loading 1500 g was evaluated first. Moreover, the finite element models of the PCB with different thickness by stacking various number of layers were discussed. In addition to changing thickness, the core material of PCB was replaced from woven E-glass/epoxy to woven carbon fiber/epoxy for structural enhancement. The non-linear material property of copper foil was considered in… More >

Ryosuke Matsuzaki^1,*, Taishi Nakamura¹, Yusuke Yamagata¹, Akira Todoroki², Masahito Ueda³, Yoshiyasu Hirano⁴

The International Conference on Computational & Experimental Engineering and Sciences, Vol.22, No.4, pp. 171-171, 2019, DOI:10.32604/icces.2019.05205

Abstract When continuous carbon fiber composites are molded with a 3D printer, three-dimensional complex structure can be integrally molded, which leads to reduction of manufacturing time and cost. In addition, because the curved continuous fibers can be printed in a plane when the 3D printer is utilized, the design space and capability of 3D printed composites will drastically expand compared with using just straight fibers such as conventional prepreg. However, printing accuracy of composite materials may be affected uniquely by parameters such as number of fibers in tow, printing curvature, compaction pressure etc. In this study,… More >

Meriem Fehri^1,2, Rachid Robleh Ragueh¹, Alexandre Vivet^1*, Fakhreddine Dammak², Mohamed Haddar²

Journal of Renewable Materials, Vol.5, No.1, pp. 38-47, 2017, DOI:10.7569/JRM.2016.634123

Abstract The purpose of this work is the improvement of flax fiber-reinforced composites obtained by vacuum molding in order to encourage their insertion into industrial products. The relatively high degree of porosity in these kinds of composites, due to the lack of compatibility between epoxy matrix and flax fibers and the hydrophilicity of flax fiber, remains a major constraint to their use in the industrial world. Hence, we have used a combination of carbon fibers with those of flax in order to optimize the properties of the assembly. Several stacking sequences have been tested in order More >

Heather L. Buckley^1*, Caitlin H. Touchberry², Jonathan P. McKinley², Zachary S. Mathe¹, Hurik Muradyan¹, Hannah Ling², Raj P. Fadadu¹, Martin J. Mulvihill¹, Susan E. Amrose²

Journal of Renewable Materials, Vol.5, No.1, pp. 1-13, 2017, DOI:10.7569/JRM.2016.634109

Abstract Waste cardboard is an underutilized resource that can be redirected for the creation of safer and higher quality building materials for low-income housing in the developing world, as well as to produce better materials for indoor environments in developed-world contexts. Using a renewable biobased binder and benign additives, we have improved the water resistance of a cardboard-based composite material, overcoming one of the major barriers to scaling and adoption of this class of materials. Resistance to water uptake was significantly increased with several additives and was increased over 900-fold in the best case. Strength and More >

Itxaso Algar¹, Clara Garcia-Astrain¹, Alba Gonzalez², Loli Martin³, Nagore Gabilondo¹, Aloña Retegi^1*, Arantxa Eceiza^1*

Journal of Renewable Materials, Vol.4, No.1, pp. 57-65, 2016, DOI:10.7569/JRM.2015.634124

Abstract Bacterial cellulose/montmorillonite (BCMMT) hybrid bionanocomposite membranes were prepared by in-situ assembling or one-step biosynthesis process. The presence of MMT in BC membranes was confi rmed by thermogravimetric analysis and quantifi ed by mass spectrometry, resulting in bionanocomposites with MMT contents between 7–13 wt%. The incorporation of MMT during BC biosynthesis modifi ed BC morphology and led to lower porosity, even though higher water holding capacity was achieved. Bionanocomposites showed improved thermal stability and water vapor and oxygen gas barrier properties up to 70 and 80% with respect to neat BC membranes. This improvement was related More >

Hao Dong¹, Yufeng Nie^1,2, Zihao Yang¹, Yang Zhang¹, Yatao Wu¹

CMES-Computer Modeling in Engineering & Sciences, Vol.111, No.5, pp. 395-419, 2016, DOI:10.3970/cmes.2016.111.395

Abstract In this paper, we discuss the numerical accuracy of asymptotic homogenization method (AHM) and multiscale finite element method (MsFEM) for periodic composite materials. Through numerical calculation of the model problems for four kinds of typical periodic composite materials, the main factors to determine the accuracy of first-order AHM and second-order AHM are found, and the physical interpretation of these factors is given. Furthermore, the way to recover multiscale solutions of first-order AHM and MsFEM is theoretically analyzed, and it is found that first-order AHM and MsFEM provide similar multiscale solutions under some assumptions. Finally, numerical More >

Henning Roedel¹, Isamar Rosa Plata¹, Michael Lepech^1,*, David Loftus²

Journal of Renewable Materials, Vol.3, No.3, pp. 183-194, 2015, DOI:10.7569/JRM.2015.634107

Abstract This article presents the sustainability assessment of a novel biocomposite material that is under investigation by NASA for use in construction in limited resource environments. The composite consists of soil particles solidified by a protein binding agent. Preliminary compressive strength data suggests the biocomposite could be used for numerous construction applications. To assess the biocomposite’s potential for use in sustainable construction, a comparative process-based life cycle assessment between biocomposite and concrete pavers was performed to analyze the life cycle primary energy and IMPACT 2002+ points of both types of pavers. Results show that the concrete More >

Y. Wang¹, E. Lü^1,2, J. Zhao¹, J. Guo¹

CMES-Computer Modeling in Engineering & Sciences, Vol.109-110, No.1, pp. 35-53, 2015, DOI:10.3970/cmes.2015.109.035

Abstract Meshfree methods have found good applications in many new researches, which show very good potential to be powerful numerical tools. As an alternative to the mesh based methods, meshfree methods have the advantage of not using a predefined mesh for the domain discretization. In this study, a mesh free scheme based on the radial point interpolation method was used to solve the topological design of microstructures for composite materials. The explicit form of the radial point interpolation method (RPIM) interpolation augmented with polynomials is presented, which satisfies range-restricted properties and is applicable to integrate a More >

T. Gortsas¹, S.V. Tsinopoulos², D. Polyzos^1,3

CMES-Computer Modeling in Engineering & Sciences, Vol.107, No.4, pp. 321-343, 2015, DOI:10.3970/cmes.2015.107.321

Abstract An advanced Boundary Element method (BEM) accelerated via Adaptive Cross Approximation (ACA) and Hierarchical Matrices (HM) techniques is presented for the solution of large-scale elastostatic problems with multi-connected domains like in fiber reinforced composite materials. Although the proposed ACA/ BEM is demonstrated for two-dimensional (2D) problems, it is quite general and it can be used for 3D problems. Different forms of ACA technique are employed for exploring their efficiency when they combined with a BEM code. More precisely, the fully and partially pivoted ACA with and without recompression are utilized, while the solution of the More >

Yu Miao¹, Zhe Chen¹, Qiao Wang^1,2, Hongping Zhu¹

CMC-Computers, Materials & Continua, Vol.43, No.1, pp. 49-74, 2014, DOI:10.3970/cmc.2014.043.049

Abstract In this paper, an improved multi-domain model based on the hybrid boundary node method (Hybrid BNM) is proposed for mechanical analysis of 3D composites. The Hybrid BNM is a boundary type meshless method which based on the modified variational principle and the Moving Least Squares (MLS) approximation. The improved multi-domain model can reduce the total degrees of freedom (DOFs) compared with the conventional multi-domain solver. It is very suitable for the inclusion-based composites, especially for the composites when the inclusions are solid and totally embedded in the matrix domain. Numerical examples are presented to verify More >