Journal articles: 'Micromechanics'

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Mahesh, C., K. Govindarajulu, and V. Balakrishna Murthy. "Simulation-based verification of homogenization approach in predicting effective thermal conductivities of wavy orthotropic fiber composite." International Journal of Computational Materials Science and Engineering 08, no. 04 (September 24, 2019): 1950015. http://dx.doi.org/10.1142/s2047684119500155.

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In this work, applicability of homogenization approach is verified with the micromechanics approach by considering wavy orthotropic fiber composite. Thermal conductivities of [Formula: see text]-300 orthotropic wavy fiber composite are determined for micromechanical model and compared with the results obtained by two stage homogenized model over volume fraction ranging from 0.1 to 0.6. Also, a methodology is suggested for reducing percentage deviation between homogenization and micromechanical approaches. Effect of debond on the thermal conductivities of wavy orthotrophic fiber composite is studied and compared with perfectly aligned fiber composite for different volume fraction. It is observed that results obtained by the homogenization approach are in good agreement with the results obtained through micromechanics approach. Maximum percentage deviation between homogenized and micromechanics models is 2.13%.

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Kim, Young Cheol, Hong-Kyu Jang, Geunsu Joo, and Ji Hoon Kim. "A Comparative Study of Micromechanical Analysis Models for Determining the Effective Properties of Out-of-Autoclave Carbon Fiber–Epoxy Composites." Polymers 16, no. 8 (April 14, 2024): 1094. http://dx.doi.org/10.3390/polym16081094.

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This study aims to critically assess different micromechanical analysis models applied to carbon-fiber-reinforced plastic (CFRP) composites, employing micromechanics-based homogenization to accurately predict their effective properties. The paper begins with the simplest Voigt and Reuss models and progresses to more sophisticated micromechanics-based models, including the Mori–Tanaka and Method of Cells (MOC) models. It provides a critical review of the areas in which these micromechanics-based models are effective and analyses of their limitations. The numerical analysis results were confirmed through finite element simulations of the periodic representative volume element (RVE). Furthermore, the effective properties predicted by these micromechanics-based models were validated via experiments conducted on IM7/5320-1 composite material with a fiber volume fraction of 0.62.

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Ovid'ko, I. A. "Micromechanics of fracturing in nanoceramics." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 373, no. 2038 (March 28, 2015): 20140129. http://dx.doi.org/10.1098/rsta.2014.0129.

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An overview of key experimental data and theoretical representations on fracture processes in nanoceramics is presented. The focuses are placed on crack growth in nanoceramics and their toughening micromechanics. Conventional toughening micromechanisms are discussed which effectively operate in both microcrystalline-matrix ceramics containing nanoinclusions and nanocrystalline-matrix ceramics. Particular attention is devoted to description of special (new) toughening micromechanisms related to nanoscale deformation occurring near crack tips in nanocrystalline-matrix ceramics. In addition, a new strategy for pronounced improvement of fracture toughness of ceramic materials through fabrication of ceramic–graphene nanocomposites is considered. Toughening micromechanisms are discussed which operate in such nanocomposites containing graphene platelets and/or few-layer sheets.

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Sertse, Hamsasew M., Johnathan Goodsell, Andrew J. Ritchey, R. Byron Pipes, and Wenbin Yu. "Challenge problems for the benchmarking of micromechanics analysis: Level I initial results." Journal of Composite Materials 52, no. 1 (April 3, 2017): 61–80. http://dx.doi.org/10.1177/0021998317702437.

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Because of composite materials’ inherent heterogeneity, the field of micromechanics provides essential tools for understanding and analyzing composite materials and structures. Micromechanics serves two purposes: homogenization or prediction of effective properties and dehomogenization or recovery of local fields in the original heterogeneous microstructure. Many micromechanical tools have been developed and codified, including commercially available software packages that offer micromechanical analyses as stand-alone tools or as part of an analysis chain. With the increasing number of tools available, the practitioner must determine which tool(s) provides the most value for the problem at hand given budget, time, and resource constraints. To date, simple benchmarking examples have been developed in an attempt to address this challenge. The present paper presents the benchmark cases and results from the Micromechanical Simulation Challenge hosted by the Composites Design and Manufacturing HUB. The challenge is a series of comprehensive benchmarking exercises in the field of micromechanics against which such tools can be compared. The Level I challenge problems consist of six microstructure cases, including aligned, continuous fibers in a matrix, with and without an interphase; a cross-ply laminate; spherical inclusions; a plain-weave fabric; and a short-fiber microstructure with “random” fiber orientation. In the present phase of the simulation challenge, the material constitutive relations are restricted to linear thermoelastic. Partial results from DIGIMAT-MF, ESI VPS, MAC/GMC, finite volume direct averaging method, Altair MDS, SwiftComp, and 3D finite element analysis are reported. As the challenge is intended to be ongoing, the full results are hosted and updated online at www.cdmHUB.org .

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Jones, Christopher A. R., Matthew Cibula, Jingchen Feng, Emma A. Krnacik, David H. McIntyre, Herbert Levine, and Bo Sun. "Micromechanics of cellularized biopolymer networks." Proceedings of the National Academy of Sciences 112, no. 37 (August 31, 2015): E5117—E5122. http://dx.doi.org/10.1073/pnas.1509663112.

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Collagen gels are widely used in experiments on cell mechanics because they mimic the extracellular matrix in physiological conditions. Collagen gels are often characterized by their bulk rheology; however, variations in the collagen fiber microstructure and cell adhesion forces cause the mechanical properties to be inhomogeneous at the cellular scale. We study the mechanics of type I collagen on the scale of tens to hundreds of microns by using holographic optical tweezers to apply pN forces to microparticles embedded in the collagen fiber network. We find that in response to optical forces, particle displacements are inhomogeneous, anisotropic, and asymmetric. Gels prepared at 21 °C and 37 °C show qualitative difference in their micromechanical characteristics. We also demonstrate that contracting cells remodel the micromechanics of their surrounding extracellular matrix in a strain- and distance-dependent manner. To further understand the micromechanics of cellularized extracellular matrix, we have constructed a computational model which reproduces the main experiment findings.

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Takahashi, Kiyoshi. "Micromechanics." Kobunshi 36, no. 10 (1987): 726–29. http://dx.doi.org/10.1295/kobunshi.36.726.

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Brighenti, Roberto, Federico Artoni, and Mattia Pancrazio Cosma. "Viscous and Failure Mechanisms in Polymer Networks: A Theoretical Micromechanical Approach." Materials 12, no. 10 (May 14, 2019): 1576. http://dx.doi.org/10.3390/ma12101576.

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Polymeric materials typically present a complex response to mechanical actions; in fact, their behavior is often characterized by viscous time-dependent phenomena due to the network rearrangement and damage induced by chains’ bond scission, chains sliding, chains uncoiling, etc. A simple yet reliable model—possibly formulated on the basis of few physically-based parameters—accounting for the main micro-scale micromechanisms taking place in such a class of materials is required to properly describe their response. In the present paper, we propose a theoretical micromechanical approach rooted in the network’s chains statistics which allows us to account for the time-dependent response and for the chains failure of polymer networks through a micromechanics formulation. The model is up-scaled to the mesoscale level by integrating the main field quantities over the so-called ‘chains configuration space’. After presenting the relevant theory, its reliability is verified through the analysis of some representative tests, and some final considerations are drawn.

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8

Ortiz, M. "Computational micromechanics." Computational Mechanics 18, no. 5 (September 1996): 321–38. http://dx.doi.org/10.1007/bf00376129.

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Ortiz, M. "Computational micromechanics." Computational Mechanics 18, no. 5 (September 1, 1996): 321–38. http://dx.doi.org/10.1007/s004660050151.

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10

Lindroos, Matti, Anssi Laukkanen, and Tom Andersson. "Micromechanical modeling of polycrystalline high manganese austenitic steel subjected to abrasive contact." Friction 8, no. 3 (December 19, 2019): 626–42. http://dx.doi.org/10.1007/s40544-019-0315-1.

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AbstractThis study focuses on microstructural and micromechanical modeling of abrasive sliding contacts of wear-resistant Hadfield steel. 3D finite element representation of the microstructure was employed with a crystal plasticity model including dislocation slip, deformation twinning, and their interactions. The results showed that deformation twinning interacting with dislocations had a key role in the surface hardening of the material, and it was also important for the early hardening process of the sub-surface grains beyond the heavily distorted surface grains. The effects of grain orientation and microstructural features were discussed and analyzed according to the micromechanical model to give a perspective to the anisotropy of the material and the feasibility of using micromechanics in virtual material design.

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11

Biscani, Fabio, Yao Koutsawa, Salim Belouettar, and Erasmo Carrera. "Effective Properties of Electro-Elastic Composites with Multi-Coating Inhomogeneities." Advanced Materials Research 93-94 (January 2010): 190–93. http://dx.doi.org/10.4028/www.scientific.net/amr.93-94.190.

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This work presents a micromechanics-based model to investigate the effective thermo-electric properties of piezoelectric composite materials. The effective thermo-electric properties are derived by considering a multi-coated ellipsoidal inhomogeneity embedded in a host material in the framework of the generalized self-consistent method (GSCM). An incremental scheme, in which the reinforcements are incrementally put in the host material, is implemented. The validation of the micromechanical model is performed with experimental data. The model proposed has a wide range of applications and can be extended to other physical properties.

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12

Koudelková, Veronika, Tereza Sajdlová, and Jiří Němeček. "Micromechanical Homogenization of Ultra-High Performance Concrete." Applied Mechanics and Materials 821 (January 2016): 518–25. http://dx.doi.org/10.4028/www.scientific.net/amm.821.518.

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Mechanical properties and durability of Ultra-High Performance Concretes (UHPC) are closely associated with composition and microstructure of tested samples. In this work, determination of effective elastic properties of UHPC composite was performed for a representative volume element using combination of microstructural investigations (scanning electron microscope imaging, image analysis of back scattered electron micrographs and nanoindentation) and analytical methods of micromechanics. Based on the volumetric content and micromechanical behavior of individual components an effective elastic modulus of the whole composite was predicted and compared with macroscopically measured value with good agreement within 5%.

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13

Araki, S., and K. Saito. "Micromechanics of Stiffness Damage in Ceramic-Based Fiber-Reinforced Composites." International Journal of Damage Mechanics 11, no. 3 (July 2002): 205–22. http://dx.doi.org/10.1106/105678902026410.

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The micromechanical analysis is performed to elucidate the stiffness reduction damage in the ceramic/ceramic composite whose matrix rupture strain is smaller than that of fibers. It is assumed that damage mechanism in the composite consists mainly of crack bridging fiber and interfacial sliding between the matrix and fibers. Energy release rate for a matrix crack and energy dissipation by the interfacial sliding was formulated by means of the inclusion modeling in micromechanics. Macroscopic stiffness at the given applied stress was derived in terms of the current lengths of matrix cracks. Finally, applicability of a parameter of damage accumulation in the material and its effect on macroscopic stiffness were discussed by the use of macroscopic stress-strain curves.

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14

Zaoui, André. "Continuum Micromechanics: Survey." Journal of Engineering Mechanics 128, no. 8 (August 2002): 808–16. http://dx.doi.org/10.1061/(asce)0733-9399(2002)128:8(808).

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15

Giovine, Pasquale. "Extended granular micromechanics." EPJ Web of Conferences 140 (2017): 11009. http://dx.doi.org/10.1051/epjconf/201714011009.

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16

Ni, Guangjian, Jia Pang, Qi Zheng, Zihao Xu, Baolu Liu, Haiyu Zhang, and Dong Ming. "Modeling cochlear micromechanics." Journal of Bio-X Research 2, no. 2 (June 2019): 68–73. http://dx.doi.org/10.1097/jbr.0000000000000034.

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17

Suo, Zhigang, Joost Vlassak, and Sigurd Wagner. "Micromechanics of macroelectronics." China Particuology 3, no. 6 (December 2005): 321–28. http://dx.doi.org/10.1016/s1672-2515(07)60210-3.

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Raiteri, Roberto, Massimo Grattarola, and Rüdiger Berger. "Micromechanics senses biomolecules." Materials Today 5, no. 1 (January 2002): 22–29. http://dx.doi.org/10.1016/s1369-7021(02)05139-8.

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Svoboda, Ladislav, Stanislav Šulc, Tomáš Janda, Jan Vorel, and Jan Novák. "μMech micromechanics library." Advances in Engineering Software 100 (October 2016): 148–60. http://dx.doi.org/10.1016/j.advengsoft.2016.07.010.

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20

Whitehouse, D. J. "Micromechanics in systems." Mechatronics 1, no. 4 (January 1991): 427–37. http://dx.doi.org/10.1016/0957-4158(91)90028-9.

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21

Michler, Goerg H. "Micromechanics of polymers." Journal of Macromolecular Science, Part B 38, no. 5-6 (September 1999): 787–802. http://dx.doi.org/10.1080/00222349908248139.

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22

Yan, Shirong, Binglei Wang, Yu Sun, and Boning Lyu. "Micromechanics-Based Prediction Models and Experimental Validation on Elastic Modulus of Recycled Aggregate Concrete." Sustainability 13, no. 20 (October 10, 2021): 11172. http://dx.doi.org/10.3390/su132011172.

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Elastic modulus is one of the most important mechanical properties of concrete (including recycled aggregate concrete), and it has a notable guiding significance for engineering. There is a lack of micromechanical research on the elastic modulus of recycled aggregate concrete. This paper adopts four models based on micromechanics, including the Voigt model, Reuss model, Eshelby method, and Mori–Tanaka method, to predict the elastic modulus of recycled aggregate concrete. The optimal model is determined by comparing the results of the four models with the experimental data. On this basis, some previous prediction methods for the elastic modulus of concrete are employed to be compared with the most satisfactory models in this paper. Several experimental data from the open literature are also utilized to better illustrate the reliability of the prediction models. It is concluded that the Mori–Tanaka method unfailingly produces more accurate predictions compared to other models. It gives the best overall approximation for various data and has extensive effects in predicting the elastic modulus of RAC. This work may be helpful in promoting the development of micromechanics research in recycled aggregate concrete.

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Pinho, S. T., R. Gutkin, S. Pimenta, N. V. De Carvalho, and P. Robinson. "On longitudinal compressive failure of carbon-fibre-reinforced polymer: from unidirectional to woven, and from virgin to recycled." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 370, no. 1965 (April 28, 2012): 1871–95. http://dx.doi.org/10.1098/rsta.2011.0429.

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Modelling the longitudinal compressive failure of carbon-fibre-reinforced composites has been attempted for decades. Despite many developments, no single model has surfaced to provide simultaneously a definitive explanation for the micromechanics of failure as well as validated predictions for a generic stress state. This paper explores the reasons for this, by presenting experimental data (including scanning electron microscopic observations of loaded kink bands during propagation, and brittle shear fracture at 45 ° to the fibres) and reviewing previously proposed micromechanical analytical and numerical models. The paper focuses mainly on virgin unidirectional (UD) composites, but studies for woven and recycled composites are also presented, highlighting similarities and differences between these cases. It is found that, while kink-band formation (also referred to in the literature as microbuckling) is predominant in UD composites under longitudinal compression, another failure mode related to the failure of the fibres can be observed experimentally. It is also shown that the micromechanics of the failure process observed in UD composites is similar to that in other fibre architectures, hence encouraging the adaptation and application of models developed for the former to the latter.

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You, Zhanping, and Qingli Dai. "Review of advances in micromechanical modeling of aggregate–aggregate interactions in asphalt mixtures." Canadian Journal of Civil Engineering 34, no. 2 (February 1, 2007): 239–52. http://dx.doi.org/10.1139/l06-113.

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This paper presents a comprehensive review of the work done by a number of researchers on the modeling of asphalt mixture. Included are some of the earliest models such as those with non-interacting particles (models with and without geometry specified), models with particle interaction, and some new models developed in recent years. The paper focuses on the description and comparison of the most recently developed finite element network model (FENM), a clustered discrete element model (DEM), and a micromechanical finite element model (FEM) used in micromechanical modeling of asphalt mixture. These models consider the complex mixture microstructure and aggregate–aggregate interaction. These models are demonstrated and applications of the advances are provided, where virtual laboratory simulation and laboratory tests were employed. The feasibility of nanotechnology application in asphalt mixture is also briefly discussed.Key words: micromechanical modeling, micromechanics, aggregate–aggregate interaction, finite elements, discrete elements, asphalt mixture.

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Karki, Pravat, Yong-Rak Kim, and Dallas N. Little. "Dynamic Modulus Prediction of Asphalt Concrete Mixtures through Computational Micromechanics." Transportation Research Record: Journal of the Transportation Research Board 2507, no. 1 (January 2015): 1–9. http://dx.doi.org/10.3141/2507-01.

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This paper presents a computational micromechanics modeling approach to predict the dynamic modulus of asphalt concrete mixtures. The modeling uses a finite element method combined with the micromechanical representative volume element (RVE) of mixtures and laboratory tests that characterize the properties of individual mixture constituents. The model treats asphalt concrete mixtures as heterogeneous with two primary phases: a linear viscoelastic fine aggregate matrix (FAM) phase and a linear elastic aggregate phase. The mechanical properties of each phase were experimentally obtained by conducting constitutive tests: oscillatory torsion tests for the viscoelastic FAM phase and quasistatic nanoindentation tests for the elastic aggregate particles. Material properties of each mixture phase were then used in the finite element simulation of two-dimensional mixture microstructures obtained from digital image processes of asphalt concrete mixtures. Model simulations were compared with the experimental dynamic moduli of asphalt concrete mixtures. Simulation results indicated that the micromechanical approach based on the mixture microstructure and phase properties could fairly predict the overall mixture properties that are typically obtained from laboratory mixture tests. Furthermore, the RVE dimension of 60 mm might be used to predict the undamaged viscoelastic stiffness characteristics of asphalt concrete mixtures with reduced computing efforts.

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Lucarini, S., M. V. Upadhyay, and J. Segurado. "FFT based approaches in micromechanics: fundamentals, methods and applications." Modelling and Simulation in Materials Science and Engineering 30, no. 2 (December 28, 2021): 023002. http://dx.doi.org/10.1088/1361-651x/ac34e1.

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Abstract FFT methods have become a fundamental tool in computational micromechanics since they were first proposed in 1994 by Moulinec and Suquet for the homogenization of composites. Since then many different approaches have been proposed for a more accurate and efficient resolution of the non-linear homogenization problem. Furthermore, the method has been pushed beyond its original purpose and has been adapted to a variety of problems including conventional and strain gradient plasticity, continuum and discrete dislocation dynamics, multi-scale modeling or homogenization of coupled problems such as fracture or multi-physics problems. In this paper, a comprehensive review of FFT approaches for micromechanical simulations will be made, covering the basic mathematical aspects and a complete description of a selection of approaches which includes the original basic scheme, polarization based methods, Krylov approaches, Fourier–Galerkin and displacement-based methods. Then, one or more examples of the applications of the FFT method in homogenization of composites, polycrystals or porous materials including the simulation of damage and fracture will be presented. The applications will also provide an insight into the versatility of the method through the presentation of existing synergies with experiments or its extension toward dislocation dynamics, multi-physics and multi-scale problems. Finally, the paper will analyze the current limitations of the method and try to analyze the future of the application of FFT approaches in micromechanics.

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Zhang, H., J. Woody Ju, WL Zhu, and KY Yuan. "A micromechanical model of elastic-damage properties of innovative pothole patching materials featuring high-toughness, low-viscosity nanomolecular resin." International Journal of Damage Mechanics 30, no. 9 (March 17, 2021): 1327–50. http://dx.doi.org/10.1177/10567895211000089.

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Innovative pothole patching materials reinforced with a high-toughness, low-viscosity nanomolecular resin, dicyclopentadiene (DCPD, C10H12), have been experimentally proven to be effective in repairing cracked asphalt pavements and can significantly enhance their durability and service life. In this paper, a three-dimensional micromechanical framework is proposed based on the micromechanics and continuum damage mechanics to predict the effective elastic-damage behaviors of this innovative pothole patching material under the splitting tension test (ASTM D6931). In this micromechanical model, irregular coarse aggregates are approximated and simulated by randomly allocated multi-layer-coated spherical particles in certain representative sizes. Fine aggregates, asphalt binder (PG64-10), cured DCPD (p-DCPD), and air voids are formulated into an isotropic elastic asphalt mastic matrix based on the multilevel homogenization approach. The theoretical micromechanical elastic-damage predictions are then systemically compared with properly designed laboratory experiments as well as three-dimensional finite elements numerical simulations for the innovative pothole patching materials.

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Huber, J. E. "Micromechanical modeling of ferroelectric films." Journal of Materials Research 21, no. 3 (March 1, 2006): 557–62. http://dx.doi.org/10.1557/jmr.2006.0082.

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Ferroelectric films are growing in significance as non-volatile memory devices, sensors, and microactuators. The stress state of the film, induced by processing or constraints such as the substrate, strongly affects device behavior. Thus, it is important to be able to model the coupled and constrained behavior of film material. This work presents a preliminary study of the application of micromechanical modeling to ferroelectric films. A self-consistent micromechanics model developed for bulk ferroelectrics is adapted for thin film behavior by incorporating several features of the microstructure, mechanical clamping by the substrate, residual stresses, and the crystallographic orientation of the film.

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Chen, Qing, Zhengwu Jiang, Hehua Zhu, J. Woody Ju, Zhiguo Yan, and Yaqiong Wang. "An Improved Micromechanical Framework for Saturated Concrete Repaired by the Electrochemical Deposition Method considering the Imperfect Bonding." Journal of Engineering 2016 (2016): 1–11. http://dx.doi.org/10.1155/2016/1894027.

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The interfaces between the deposition products and concrete are not always well bonded when the electrochemical deposition method (EDM) is adopted to repair the deteriorated concrete. To theoretically illustrate the deposition healing process by micromechanics for saturated concrete considering the imperfect interfaces, an improved micromechanical framework with interfacial transition zone (ITZ) is proposed based on our recent studies. In this extension, the imperfect bonding is characterized by the ITZ, whose effects are calculated by modifying the generalized self-consistent model. Meanwhile, new multilevel homogenization schemes are employed to predict the effective properties of repaired concrete considering the ITZ effects. Moreover, modification procedures are presented to reach the properties of repaired concrete with ITZs in the dry state. To demonstrate the feasibility of the proposed micromechanical model, predictions obtained via the proposed micromechanical model are compared with those of the existing models and the experimental data, including results from extreme states during the EDM healing process. Finally, the influences of ITZ and deposition product on the healing effectiveness of EDM are discussed based on the proposed micromechanical model.

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Yu, Wenbin. "An Introduction to Micromechanics." Applied Mechanics and Materials 828 (March 2016): 3–24. http://dx.doi.org/10.4028/www.scientific.net/amm.828.3.

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This article provides a brief introduction to micromechanics using linear elastic materials as an example. The fundamental micromechanics concepts including homogenization and dehomogenization, representative volume element (RVE), unit cell, average stress and strain theories, effective stiffness and compliance, Hill-Mandel macrohomogeneity condition. This chapter also describes the detailed derivations of the rules of mixtures, and three full field micromechanics theories including finite element analysis of a representative volume element (RVE analysis), mathematical homogenization theory (MHT), and mechanics of structure genome (MSG). Theoretical connections among the three full field micromechanics theories are clearly shown. Particularly, it is shown that RVE analysis, MHT and MSG are governed by the same set of equations for 3D RVEs with periodic boundary conditions. RVE analysis and MSG can also handle aperiodic or partially periodic materials for which MHT is not applicable. MSG has the unique capability to obtain the complete set of 3D properties and local fields for heterogeneous materials featuring 1D or 2D heterogeneities.

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Wang, Guannan, Qiang Chen, Mengyuan Gao, Bo Yang, and David Hui. "Generalized locally-exact homogenization theory for evaluation of electric conductivity and resistance of multiphase materials." Nanotechnology Reviews 9, no. 1 (February 13, 2020): 1–16. http://dx.doi.org/10.1515/ntrev-2020-0001.

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AbstractThe locally-exact homogenization theory is further extended to investigate the homogenized and localized electric behavior of unidirectional composite and porous materials. Distinct from the classical and numerical micromechanics models, the present technique is advantageous by developing exact analytical solutions of repeating unit cells (RUC) with hexagonal and rhomboid geometries that satisfy the internal governing equations and fiber/matrix interfacial continuities in a point-wise manner. A balanced variational principle is proposed to impose the periodic boundary conditions on mirror faces of an RUC, ensuring rapid convergence of homogenized and localized responses. The present simulations are validated against the generalized Eshelby solution with electric capability and the finite-volume direct averaging micromechanics, where excellent agreements are obtained. Several micromechanical parameters are then tested of their effects on the responses of composites, such as the fiber/matrix ratio and RUC geometry. The efficiency of the theory is also proved and only a few seconds are required to generate a full set of properties and concomitant local electric fields in an uncompiled MATLAB environment. Finally, the related programs may be encapsulated with an input/output (I/O) interface such that even non-professionals can execute the programs without learning the mathematical details.

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Antin, Kim-Niklas, Anssi Laukkanen, Tom Andersson, Danny Smyl, and Pedro Vilaça. "A Multiscale Modelling Approach for Estimating the Effect of Defects in Unidirectional Carbon Fiber Reinforced Polymer Composites." Materials 12, no. 12 (June 12, 2019): 1885. http://dx.doi.org/10.3390/ma12121885.

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A multiscale modelling approach was developed in order to estimate the effect of defects on the strength of unidirectional carbon fiber composites. The work encompasses a micromechanics approach, where the known reinforcement and matrix properties are experimentally verified and a 3D finite element model is meshed directly from micrographs. Boundary conditions for loading the micromechanical model are derived from macroscale finite element simulations of the component in question. Using a microscale model based on the actual microstructure, material parameters and load case allows realistic estimation of the effect of a defect. The modelling approach was tested with a unidirectional carbon fiber composite beam, from which the micromechanical model was created and experimentally validated. The effect of porosity was simulated using a resin-rich area in the microstructure and the results were compared to experimental work on samples containing pores.

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Hou, Yueqin, Yun Chen, Haiwei Zou, Xiaoping Ji, Dongye Shao, Zhengming Zhang, and Ye Chen. "Investigation of Surface Micro-Mechanical Properties of Various Asphalt Binders Using AFM." Materials 15, no. 12 (June 20, 2022): 4358. http://dx.doi.org/10.3390/ma15124358.

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The microstructure of asphalt affects the micro-mechanical properties. In this study, atomic force microscopy (AFM) was used to investigate the surface elastic modulus and nanohardness of asphalt binder. Relevant mechanical indexes were quantitatively evaluated by contact mechanical model. Five types of asphalts, including different grades, oil sources, and before and after modification, were selected as test objects, and the effects of asphalt binder type, aging, water, and anti-stripping agent on the asphalt micromechanics were explored. The results showed that the micromechanical properties of asphalt binder are affected by grade, oil source, and modification. The aging resistance of modified asphalt binder is better than that of unmodified asphalt binder. Water immersion reduces the surface micromechanical properties of the asphalt binder. The effect of the anti-stripping agent on the modified asphalt binder is greater than that of the unmodified asphalt binder.

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Mamache, Fateh Enouar, Amar Mesbah, Fahmi Zaïri, and Iurii Vozniak. "A Coupled Electro-Mechanical Homogenization-Based Model for PVDF-Based Piezo-Composites Considering α → β Phase Transition and Interfacial Damage." Polymers 15, no. 14 (July 10, 2023): 2994. http://dx.doi.org/10.3390/polym15142994.

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Polyvinylidene fluoride or polyvinylidene difluoride (PVDF) is a piezoelectric semi-crystalline polymer whose electro-mechanical properties may be modulated via strain-induced α → β phase transition and the incorporation of polarized inorganic particles. The present work focuses on the constitutive representation of PVDF-based piezo-composites developed within the continuum-based micromechanical framework and considering the combined effects of particle reinforcement, α → β phase transition, and debonding along the interface between the PVDF matrix and the particles under increasing deformation. The micromechanics-based model is applied to available experimental data of PVDF filled with various concentrations of barium titanate (BaTiO3) particles. After its identification and predictability verification, the model is used to provide a better understanding of the separate and synergistic effects of BaTiO3 particle reinforcement and the micromechanical deformation processes on the electro-mechanical properties of PVDF-based piezo-composites.

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Luo, Yunhua. "An Accuracy Comparison of Micromechanics Models of Particulate Composites against Microstructure-Free Finite Element Modeling." Materials 15, no. 11 (June 6, 2022): 4021. http://dx.doi.org/10.3390/ma15114021.

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Micromechanics models of composite materials are preferred in the analysis and design of composites for their high computational efficiency. However, the accuracy of the micromechanics models varies widely, depending on the volume fraction of inclusions and the contrast of phase properties, which have not been thoroughly studied, primarily due to the lack of complete and representative experimental data. The recently developed microstructure-free finite element modeling (MF-FEM) is based on the fact that, for a particulate-reinforced composite, if the characteristic size of the inclusions is much smaller than the composite representative volume element (RVE), the elastic properties of the RVE are independent of inclusion shape and size. MF-FEM has a number of advantages over the conventional microstructure-based finite element modeling. MF-FEM predictions have good to excellent agreement with the reported experiment results. In this study, predictions produced by MF-FEM are used in replace of experimental data to compare the accuracy of selected micromechanics models of particulate composites. The results indicate that, only if both the contrasts in phase Young’s moduli and phase Poisson’s ratios are small, the micromechanics models are able to produce accurate predictions. In other cases, they are more or less inaccurate. This study may serve as a guide for the appropriate use of the micromechanics models.

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Luo, Yunhua. "An Accuracy Comparison of Micromechanics Models of Particulate Composites against Microstructure-Free Finite Element Modeling." Materials 15, no. 11 (June 6, 2022): 4021. http://dx.doi.org/10.3390/ma15114021.

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Micromechanics models of composite materials are preferred in the analysis and design of composites for their high computational efficiency. However, the accuracy of the micromechanics models varies widely, depending on the volume fraction of inclusions and the contrast of phase properties, which have not been thoroughly studied, primarily due to the lack of complete and representative experimental data. The recently developed microstructure-free finite element modeling (MF-FEM) is based on the fact that, for a particulate-reinforced composite, if the characteristic size of the inclusions is much smaller than the composite representative volume element (RVE), the elastic properties of the RVE are independent of inclusion shape and size. MF-FEM has a number of advantages over the conventional microstructure-based finite element modeling. MF-FEM predictions have good to excellent agreement with the reported experiment results. In this study, predictions produced by MF-FEM are used in replace of experimental data to compare the accuracy of selected micromechanics models of particulate composites. The results indicate that, only if both the contrasts in phase Young’s moduli and phase Poisson’s ratios are small, the micromechanics models are able to produce accurate predictions. In other cases, they are more or less inaccurate. This study may serve as a guide for the appropriate use of the micromechanics models.

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Garnich, M. R., and A. C. Hansen. "A Multicontinuum Approach to Structural Analysis of Linear Viscoelastic Composite Materials." Journal of Applied Mechanics 64, no. 4 (December 1, 1997): 795–803. http://dx.doi.org/10.1115/1.2788984.

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A “multicontinuum” approach to structural analyses of composites is described. A continuum field is defined to represent each constituent material along with the traditional continuum field associated with the composite. Finite element micromechanics is used to establish relationships between composite and constituent field variables. These relationships uncouple the micromechanics from structural solutions and render an efficient means of extracting constituent information during the course of a finite element structural analysis. Equations are developed for the case of a linear elastic reinforcing material embedded in a linear viscoelastic matrix and verified by comparison with results of finite element micromechanics.

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Sierra Beltran, M. G., and Erik Schlangen. "Wood Fibre Reinforced Cement Matrix: A Micromechanical Based Approach." Key Engineering Materials 385-387 (July 2008): 445–48. http://dx.doi.org/10.4028/www.scientific.net/kem.385-387.445.

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In this paper a micromechanics-based design is proposed for the development of a material with enhanced ductility and flexural strength combined with low production cost. The composite performance is described by 11 micromechanical properties of the system consisting of cement matrix, fibres and fibre-matrix interface. Most of these properties are defined through laboratory tests. A strain-hardening behaviour with multiple microcracks prior to failure is is the goal for the composite with enhanced ductility. The amount and size of the fibres needed for bridging the microcracks as well as the composition of the cement matrix will be determined in order to achieve this behaviour.

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Schott, Walter. "Developments in Homodyne Interferometry." Key Engineering Materials 437 (May 2010): 84–88. http://dx.doi.org/10.4028/www.scientific.net/kem.437.84.

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The trend in many fields of enabling technologies, such as microelectronics, communications, microsystems, and micromechanics, toward imposing increasingly stringent demands upon precision continues. Those types of technologies allow creating micromechanical components having dimensions of a few micrometers that have to be accurately measured, positioned relative to one another, and assembled. In that conjunction, laser-interferometric metrology provides unique opportunities that combine measurements over large ranges at extraordinarily fine resolutions with traceability of measurement results to international length standards. Laser-interferometric metrological systems may be used for measuring displacements ranging from subnanometers to several meters, without need for reconfiguring the optical or electronic systems involved or their component devices.

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Rosca, Victoria Elena, Nicolae Ţăranu, Liliana Bejan, and Andrei Octav Axinte. "Element Free Galerkin Formulation for Problems in Composite Micromechanics." Applied Mechanics and Materials 809-810 (November 2015): 896–901. http://dx.doi.org/10.4028/www.scientific.net/amm.809-810.896.

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The heterogeneity and anisotropy of structural composites make the application of the standard mesh-based methods using the meshing of interfacial region between matrix and fibers a difficult task. The objective of this study is to present the EFG formulation for problems of composite micromechanics. It is expected that the tediousness and approximations involved in mesh generation, and hence inaccuracies in the results can be avoided using the new meshless techniques such as the Element Free Galerkin (EFG) method. The theoretical methodologies, computer implementations and practical application are carried out. Periodic boundary conditions of the unit cell under tensile load are set up. The method of Lagrange multipliers is introduced for the treatment of material discontinuity at the fiber-matrix interface in which both the displacement continuity and traction reciprocity are satisfied. The EFG method is formulated for the generalized plane strain problems. Examples are presented to illustrate the effectiveness of the proposed micromechanical model, and it is validated by comparing the results with available numerical solutions.

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Zhang, Yingmin, Guang Yang, Dongxu Liu, Wenwu Chen, and Lizhi Sun. "Micromechanics and Ultrasonic Propagation in Consolidated Earthen-Site Soils." Materials 16, no. 22 (November 10, 2023): 7117. http://dx.doi.org/10.3390/ma16227117.

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Although nondestructive ultrasonic technologies have been applied in laboratory and field tests in the field of heritage conservation, few studies have quantified the relationship among the real microstructures, micromechanical properties, and macroscopic acoustic responses of earthen-site soils. This paper develops a micromechanics-based multiscale model for quantitatively exploring the ultrasonic propagation characteristics of elastic waves in untreated and consolidated earthen-site soils. Scanning electron microscope images and image processing technology are integrated into the finite-element simulation. The effects of microstructure and wave features on the acoustic characteristics of soils are quantitatively investigated under pulsive loading. The simulation results of untreated and consolidated soils are efficiently compared to ultrasonic test data. It is demonstrated that the integration of microstructure image processing and multiscale modeling can predict the ultrasonic pulse velocity well, which improves the accuracy of laboratory testing and field monitoring and better serves the evaluation and implementation of engineering practice in the field of heritage conservation.

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Choudhry, RS, Kamran A. Khan, Sohaib Z. Khan, Muhammad A. Khan, and Abid Hassan. "Micromechanical modeling of 8-harness satin weave glass fiber-reinforced composites." Journal of Composite Materials 51, no. 5 (July 28, 2016): 705–20. http://dx.doi.org/10.1177/0021998316649782.

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This study introduces a unit cell-based finite element micromechanical model that accounts for correct post cure fabric geometry, in situ material properties and void content within the composite to accurately predict the effective elastic orthotropic properties of 8-harness satin weave glass fiber-reinforced phenolic composites. The micromechanical model utilizes a correct post cure internal architecture of weave, which was obtained through X-ray microtomography tests. Moreover, it utilizes an analytical expression to update the input material properties to account for in situ effects of resin distribution within yarn (the yarn volume fraction) and void content on yarn and matrix properties. This is generally not considered in modeling approaches available in literature and in particular, it has not been demonstrated before for finite element micromechanics models of 8-harness satin weave composites. The unit cell method is used to obtain the effective responses by applying periodic boundary conditions. The outcome of the analysis based on the proposed model is validated through experiments. After validation, the micromechanical model was further utilized to predict the unknown effective properties of the same composite.

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Wang, Guannan, Wenqiong Tu, and Qiang Chen. "Characterization of Interphase/Interface Parameters of Unidirectional Fibrous Composites by Optimization-Based Inverse Homogenization." International Journal of Applied Mechanics 11, no. 08 (September 2019): 1950074. http://dx.doi.org/10.1142/s1758825119500741.

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Optimization-based micromechanical and inverse-homogenization models are developed to inversely calculate the interphase/interface properties of unidirectional periodic fibrous composites from prescribed effective properties or localized stress concentrations. The interphase/interface effects between fibers and the surrounding matrix are described by four different mathematical models that are reviewed in the present work. In order to guarantee the stability of the characterization process, two sophisticated micromechanical models, locally exact homogenization theory and finite-volume direct averaging micromechanics, are introduced in this work and connected to the gradient-free particle swarm optimization to search for the optimal parameters to minimize the cost/objective functions that consider the homogenized or localized responses of unidirectional composites. The accuracy and efficiency of the proposed procedure are tested by substituting the optimized parameters back into the direct micromechanical models and validating against the target functions, where good agreement is always obtained. More importantly, the numerical effects generated by those parameters are also tested on the effective properties and localized stress distributions of fibrous composites.

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Seyedkavoosi, S., and I. Sevostianov. "Micromechanics of Dentin: Review." Reviews on advanced materials and technologies 1, no. 1 (2019): 1–26. http://dx.doi.org/10.17586/2687-0568-2019-1-1-1-26.

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MINAGAWA, Sitiro. "Recent developments in micromechanics." Journal of the Japan Society for Precision Engineering 54, no. 6 (1988): 1012–16. http://dx.doi.org/10.2493/jjspe.54.1012.

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KOBAYASHI, Hideo. "Micromechanics of crack growth." Journal of the Japan Society for Precision Engineering 54, no. 6 (1988): 1035–39. http://dx.doi.org/10.2493/jjspe.54.1035.

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Mori, Tsutomu. "Micromechanics I ～Basic Discussion～." Materia Japan 55, no. 9 (2016): 416–20. http://dx.doi.org/10.2320/materia.55.416.

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Hu, Geng Kai, and Zhu Ping Huang. "Micromechanics of Nonlinear Composites." Key Engineering Materials 274-276 (October 2004): 35–42. http://dx.doi.org/10.4028/www.scientific.net/kem.274-276.35.

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Mori, T. "Mechanical Metallurgy and Micromechanics." Materials Transactions, JIM 41, no. 4 (2000): 463–69. http://dx.doi.org/10.2320/matertrans1989.41.463.

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Perlman, Carrie E., David J. Lederer, and Jahar Bhattacharya. "Micromechanics of Alveolar Edema." American Journal of Respiratory Cell and Molecular Biology 44, no. 1 (January 2011): 34–39. http://dx.doi.org/10.1165/rcmb.2009-0005oc.

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Journal articles on the topic 'Micromechanics'

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