Effective Elastic Properties of 3D Composites with Short Curvilinear Fibers: Numerical Simulation and Experimental Validation

Theoretical and experimental estimation of elastic properties of two-phase composites containing matrix material and arc-shaped cylindrical fibers is given. Theoretical aspect consists in hybrid micro-macro formulation of problem with consideration of two associated subproblems –numerical simulation of fiber influence on the representative volume element and effective strain-stress field approximation by the averaging procedures. Boundary element method is applied for the solution of micro-level subproblem as well as Mori-Tanaka model is adopted for the overall description of composite properties at the macro-level. Then interfacial displacements are involved into solution scheme only. The effective elastic moduli of arc-fiber-reinforced composites are analyzed for the different materials combinations and fiber fractions. For the validation of numerical results, the prismatic concrete specimen filled by the curvilinear shaped cylindrical steel fibers under compression is investigated experimentally. Comparison of theoretical and experimental data is made.

Download Full-text

Micromechanics and Effective Elastoplastic Behavior of Two-Phase Metal Matrix Composites

Journal of Engineering Materials and Technology ◽

10.1115/1.2904293 ◽

1994 ◽

Vol 116 (3) ◽

pp. 310-318 ◽

Cited By ~ 52

Author(s):

J. W. Ju ◽

Tsung-Muh Chen

Keyword(s):

Metal Matrix Composites ◽

Elastic Properties ◽

Metal Matrix ◽

Phase Particle ◽

Matrix Material ◽

Flow Rule ◽

Plastic Behavior ◽

Matrix Composites ◽

Two Phase ◽

The Matrix

A micromechanical framework is presented to predict effective (overall) elasto-(visco-)plastic behavior of two-phase particle-reinforced metal matrix composites (PRMMC). In particular, the inclusion phase (particle) is assumed to be elastic and the matrix material is elasto-(visco-)plastic. Emanating from Ju and Chen’s (1994a,b) work on effective elastic properties of composites containing many randomly dispersed inhomogeneities, effective elastoplastic deformations and responses of PRMMC are estimated by means of the “effective yield criterion” derived micromechanically by considering effects due to elastic particles embedded in the elastoplastic matrix. The matrix material is elastic or plastic, depending on local stress and deformation, and obeys general plastic flow rule and hardening law. Arbitrary (general) loadings and unloadings are permitted in our framework through the elastic predictor-plastic corrector two-step operator splitting methodology. The proposed combined micromechanical and computational approach allows us to estimate overall elastoplastic responses of PRMMCs by accounting for the microstructural information (such as the spatial distribution and micro-geometry of particles), elastic properties of constituent phases, and the plastic behavior of the matrix-only materials. Comparison between our theoretical predictions and experimental data on uniaxial elastoplastic tests for PRMMCs is also presented to illustrate the capability of the proposed framework. A straightforward extension to accommodate viscoplastic matrix material is also presented to further enhance the applicability of the proposed method.

Download Full-text

A micropolar model for elastic properties in functionally graded materials

Advances in Mechanical Engineering ◽

10.1177/1687814018789520 ◽

2018 ◽

Vol 10 (8) ◽

pp. 168781401878952 ◽

Cited By ~ 1

Author(s):

Shengyao Fan ◽

Zhanqi Cheng

Keyword(s):

Particle Size ◽

Elastic Properties ◽

Functionally Graded Materials ◽

Effective Properties ◽

Matrix Material ◽

Functionally Graded ◽

Two Phase ◽

Graded Materials ◽

Micromechanics Model ◽

Matrix Zone

By considering the description of phase volume fractions, a micromechanics model is presented for predicting the elastic mechanical properties of isotropic two-phase functionally graded materials. The particle size dependence of the overall elasticity of functionally graded materials is not generally considered by classical continuum micromechanics; however, being based on micropolar theory, the presented micromechanics model is able to study such size effects. As the effective material properties vary gradually along the gradation direction, a functionally graded material can be divided into two distinct zones: the particle–matrix zone and the transition zone. In the particle–matrix zone, the matrix material is idealized as a micropolar continuum and Mori–Tanaka’s method is extended to the micropolar medium to evaluate the effective elastic properties. The effective properties across the gradation forms are further derived and the effects of particle size on the effective properties of a functionally graded materials are also studied. The validity and effectiveness of the present model is demonstrated by comparing the model results with other model outputs and experimental data.

Download Full-text

Change in the acoustic and elastic properties of the cylindrical steel specimens during the tensile

10.22213/2658-3658-2019-76-84 ◽

2019 ◽

Author(s):

Olga V. Murav'eva ◽

◽

Sergey V. Len'kov ◽

Alexandr A. Nagovitsyn ◽

Albina F. Basharova

Keyword(s):

Elastic Properties ◽

Cylindrical Steel

Download Full-text

Micromechanical analysis of effective mechanical properties of graphene/ZrO2-hybrid poly (methyl methacrylate) nanocomposites

Journal of Micromanufacturing ◽

10.1177/25165984211038861 ◽

2021 ◽

pp. 251659842110388

Author(s):

Ankit Rathi ◽

S. I. Kundalwal

Keyword(s):

Methyl Methacrylate ◽

Elastic Properties ◽

Mechanical Performance ◽

Volume Fraction ◽

Element Model ◽

Two Phase ◽

Effective Elastic Properties ◽

Poly Methyl Methacrylate ◽

Three Phase ◽

Effective Mechanical Properties

In this study, the tensile properties of two-phase and three-phase graphene/ZrO2-hybrid poly (methyl methacrylate) (PMMA) nanocomposites are investigated by developing finite element model using ANSYS. Primarily, the effective elastic properties of two- and three-phase graphene/ZrO2-hybrid PMMA nanocomposites (GRPCs) are estimated by developing mechanics of material (MOM) model. Results indicated that the effective elastic properties of GRPCs increase with an increase in the volume fraction of graphene. Also, the stiffness of GRPCs is increased by 78.12% with increasing in the volume fraction of graphene from 0.1 to 0.5 Vf. The incorporation of an additional ZrO2 interphase significantly improved the mechanical performance of resulting GRPCs.

Download Full-text

An evaluation of elastic properties and coefficients of thermal expansion of graphite fibres from macroscopic composite input data

Proceedings of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rspa.2004.1358 ◽

2005 ◽

Vol 461 (2054) ◽

pp. 347-369 ◽

Cited By ~ 5

Author(s):

P. Rupnowski ◽

M. Gentz ◽

J. K. Sutter ◽

M. Kumosa

Keyword(s):

Thermal Expansion ◽

Elastic Properties ◽

Input Data ◽

Matrix Material ◽

Unidirectional Composite ◽

Woven Composites ◽

Woven Composite ◽

Temperature Dependent ◽

Fibre Properties ◽

Representative Unit Cell

In this work, a methodology has been presented for the evaluation of stiffness properties and temperature–dependent coefficients of thermal expansion of continuous fibres from the macroscopic properties of either unidirectional or woven composites. The methodology was used to determine the stiffness and thermal properties of T650–35 graphite fibres from the macroscopic input data of unidirectional and woven composites based on the same fibres embedded in a PMR–15 polyimide matrix. In the first part of the analysis, the fibre properties were determined directly from the unidirectional composite macro data using the inversed Eshelby–Mori–Tanaka approach. Subsequently, certain fibre properties were additionally evaluated indirectly from the woven composite, using the finite–element method and the concept of a representative unit cell. It has been shown that the temperature–dependent coefficients of thermal expansion of the fibres can be estimated from the unidirectional composite macro data with significantly smaller errors than in the case of the elastic properties. It has also been shown that the errors in the evaluation of the elastic properties of the fibres from the macro unidirectional composite data could be significantly reduced if the fibres were placed in a stiff matrix material: much stiffer than the polyimide resin. The longitudinal and transverse coefficients of thermal expansions and the shear modulus of the T650–35 fibres determined from the unidirectional composite analysis were successfully verified by investigating the woven composite.

Download Full-text

Effect of Reactive SPS on the Microstructure and Properties of a Dual-Phase Ni-Al Intermetallic Compound and Ni-Al-TiB2 Composite

Materials ◽

10.3390/ma13245668 ◽

2020 ◽

Vol 13 (24) ◽

pp. 5668

Author(s):

Paweł Hyjek ◽

Iwona Sulima ◽

Piotr Malczewski ◽

Krzysztof Bryła ◽

Lucyna Jaworska

Keyword(s):

Intermetallic Compound ◽

Tribological Properties ◽

Matrix Material ◽

Dual Phase ◽

Compression Tests ◽

Two Phase ◽

Alloy Matrix ◽

Plastic Properties ◽

Mechanical And Tribological Properties ◽

The Matrix

As part of the tests, a two-phase NiAl/Ni3Al alloy and a composite based on this alloy with 4 vol% addition of TiB2 were produced by the reactive FAST/SPS (Field Assisted Sintering Technology/Spark Plasma Sintering) sintering method. The sintering process was carried out at 1273 K for 30 s under an argon atmosphere. The effect of reactive SPS on the density, microstructure, and mechanical and tribological properties of a dual-phase Ni-Al intermetallic compound and Ni-Al-TiB2 composite was investigated. Products obtained were characterized by a high degree of sintering (over 99% of the theoretical density). The microstructure of sinters was characterized by a large diversity, mainly in regard to the structure of the dual-phase alloy (matrix). Compression tests showed satisfactory plastic properties of the manufactured materials, especially at high temperature (1073 K). For both materials at room temperature, the compressive strength was over 3 GPa. The stress–strain curves were observed to assume a different course for the matrix material and composite material, including differences in the maximum plastic flow stress depending on the test temperature. The brittle-to-ductile transition temperature was determined to be above 873 K. The research has revealed differences in the physical, mechanical and tribological properties of the produced sinters. However, the differences favourable for the composite were mostly the result of the addition of TiB2 ceramic particles uniformly distributed on grain boundaries.

Download Full-text

Elasticity of Phases in Fe-Al-Ti Superalloys: Impact of Atomic Order and Anti-Phase Boundaries

Crystals ◽

10.3390/cryst9060299 ◽

2019 ◽

Vol 9 (6) ◽

pp. 299 ◽

Cited By ~ 3

Author(s):

Martin Friák ◽

Vilma Buršíková ◽

Naděžda Pizúrová ◽

Jana Pavlů ◽

Yvonna Jirásková ◽

...

Keyword(s):

Solid Solution ◽

Chemical Composition ◽

Elastic Properties ◽

Formation Energy ◽

Chemical Species ◽

Two Phase ◽

Nano Structure ◽

The Matrix ◽

Free Material ◽

Excess Fe

We combine theoretical and experimental tools to study elastic properties of Fe-Al-Ti superalloys. Focusing on samples with chemical composition Fe71Al22Ti7, we use transmission electron microscopy (TEM) to detect their two-phase superalloy nano-structure (consisting of cuboids embedded into a matrix). The chemical composition of both phases, Fe66.2Al23.3Ti10.5 for cuboids and Fe81Al19 (with about 1% or less of Ti) for the matrix, was determined from an Energy-Dispersive X-ray Spectroscopy (EDS) analysis. The phase of cuboids is found to be a rather strongly off-stoichiometric (Fe-rich and Ti-poor) variant of Heusler Fe2TiAl intermetallic compound with the L21 structure. The phase of the matrix is a solid solution of Al atoms in a ferromagnetic body-centered cubic (bcc) Fe. Quantum-mechanical calculations were employed to obtain an insight into elastic properties of the two phases. Three distributions of chemical species were simulated for the phase of cuboids (A2, B2 and L21) in order to determine a sublattice preference of the excess Fe atoms. The lowest formation energy was obtained when the excess Fe atoms form a solid solution with the Ti atoms at the Ti-sublattice within the Heusler L21 phase (L21 variant). Similarly, three configurations of Al atoms in the phase of the matrix with different level of order (A2, B2 and D03) were simulated. The computed formation energy is the lowest when all the 1st and 2nd nearest-neighbor Al-Al pairs are eliminated (the D03 variant). Next, the elastic tensors of all phases were calculated. The maximum Young’s modulus is found to increase with increasing chemical order. Further we simulated an anti-phase boundary (APB) in the L21 phase of cuboids and observed an elastic softening (as another effect of the APB, we also predict a significant increase of the total magnetic moment by 140% when compared with the APB-free material). Finally, to validate these predicted trends, a nano-scale dynamical mechanical analysis (nanoDMA) was used to probe elasticity of phases. Consistent with the prediction, the cuboids were found stiffer.

Download Full-text