Author: Hongwei Li
Publisher:
ISBN:
Category : Functionally gradient materials
Languages : en
Pages : 138

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Book Description

Author: G.H. Paulino
Publisher: Elsevier
ISBN: 9780080441603
Category : Science
Languages : en
Pages : 306

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Book Description
Scientific research on functionally graded materials (FGM's) looks at functions of gradients in materials comprising thermodynamic, mechanical, chemical, optical, electromagnetic, and/or biological aspects. This collection of technical papers represents current research interests with regard to the fracture behaviour of FGM's. The papers provide a balance between theoretical, computational, and experimental techniques. It also indicates areas for increased development, such as constraint effects, full experimental characterization of engineering FGM's under static and dynamic loading, development of fracture criteria with predictive capability, multiphysics and multiscale failure considerations, and connection of research with industrial applications.

Author: Haider Khazal
Publisher:
ISBN:
Category : Digital image correlation
Languages : en
Pages : 11

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Book Description
This research reports the computation of the fracture parameters, namely T-stress and stress intensity factors of a stepwise functionally graded material (FGM) by using the digital image correlation technique. A five-layer epoxy/glass FGM with layers varying from pure epoxy to 60 % glass/40 % epoxy was investigated. The effects of the crack-tip positions and crack length on the nonsingular terms were analyzed. In addition, the numerical simulation of the layered FGM was investigated to further evaluate the fracture parameters. The numerical and experimental model results were compared, and good agreement was obtained between the experimental and numerical tests. Accordingly, the numerical models developed with the corresponding material properties can be used for the evaluation of fracture parameters of the developed FGM.

Author: Arun P. Kaile
Publisher:
ISBN:
Category :
Languages : en
Pages : 336

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Book Description

Author: Carl-Ernst Rousseau
Publisher:
ISBN:
Category : Fracture mechanics
Languages : en
Pages : 398

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Book Description

Author: G. H. Paulino
Publisher:
ISBN:
Category :
Languages : en
Pages : 294

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Book Description

Author: Tian Xiaohong
Publisher: Walter de Gruyter GmbH & Co KG
ISBN: 3110297973
Category : Science
Languages : en
Pages : 317

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Book Description
Mechanical responses of solid materials are governed by their material properties. The solutions for estimating and predicting the mechanical responses are extremely difficult, in particular for non-homogeneous materials. Among these, there is a special type of materials whose properties are variable only along one direction, defined as graded materials or functionally graded materials (FGMs). Examples are plant stems and bones. Artificial graded materials are widely used in mechanical engineering, chemical engineering, biological engineering, and electronic engineering. This work covers and develops boundary element methods (BEM) to investigate the properties of realistic graded materials. It is a must have for practitioners and researchers in materials science, both academic and in industry. Covers analysis of properties of graded materials. Presents solutions based methods for analysis of fracture mechanics. Presents two types of boundary element methods for layered isotropic materials and transversely isotropic materials. Written by two authors with extensive international experience in academic and private research and engineering.

Author: Ray Douglas Carpenter
Publisher:
ISBN: 9781303151064
Category :
Languages : en
Pages :

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Book Description
The primary objective of this research was to extend established fracture toughnesstesting methods to a new class of engineering materials known as functionally gradedmaterials (FGMs). Secondary goals were to compare experimental results to thosepredicted by finite element models and to provide fracture test results as feedback towardoptimizing processing parameters for the in-house synthesis of a MoSi2/SiC FGM.Preliminary experiments were performed on commercially pure (CP) Ti and uniformaxial tensile tests resulted in mechanical property data including yield strength, 268 MPa,ultimate tensile strength, 470 MPa and Young's modulus, 110 GPa. Results from 3-pointbending fracture experiments on CP Ti demonstrated rising R-curve behavior andexperimentally determined J[Q] fracture toughness values ranged between 153 N/mm and254 N/mm. Similar experimental protocols were used for fracture experiments on a 7-layered Ti/TiB FGM material obtained from Cercom in Vista, California. A noveltechnique for pre-cracking in reverse 4-point bending was developed for thisductile/brittle FGM material. Fracture test results exhibited rising R-curve behavior and estimated J[Q] fracture toughness values ranged from 0.49 N/mm to 2.63 N/mm. A 5-layered MoSi2/SiC FGM was synthesized using spark plasma sintering (SPS). Samples ofthis material were fracture tested and the results again exhibited a rising R-curve with K[IC] fracture toughness values ranging from 2.7 MPa-m1/2 to 6.0 MPa-m1/2. Finite Element Models predicted rising R-curve behavior for both of the FGM materials tested. Modelresults were in close agreement for the brittle MoSi2/SiC FGM. For the relatively moreductile Ti/TiB material, results were in close agreement at short crack lengths butdiverged at longer crack lengths because the models accounted for fracture tougheningmechanisms at the crack tip but not those acting in the crack wake.

Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 0

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Book Description
After three years of the project, many of the proposed research topics have been completed and manuscripts were submitted for publication. First, for the dynamic crack propagation within functionally graded materials (FGMs), a novel fracture criterion was introduced. It is based on energy concept and controls crack growth rate and associated plastic dissipation flow. This model was implemented in dynamic failure analysis to investigate crack propagation within elastic plastic graded materials. The new procedure was also implemented for the impact of graded protective layer. The results confirmed the importance of modeling of cracking, revealed the effects of compositional gradation through-thickness. In a subsequent analysis, a procedure that utilizes an inverse analysis was developed to measure key fracture parameters. These parameters are difficult to measure with conventional means. Third, in collaboration with materials science group, material parameters of actual FGM were measured using the indentation and inverse method. The specimens were thermal barrier coatings fabricated with zirconia and NiCrAlY. This type of advanced scheme to post-process experimental data is essential for obtaining properties of complex systems. In addition, preliminary fracture tests were conducted for thicker FGMs to determine its fracture behavior.

Author: P. H. Wen
Publisher: Computational Mechanics
ISBN: 9781853124464
Category : Technology & Engineering
Languages : en
Pages : 202

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Book Description
This work describes the formulation and numerical implementation of both two- and three-dimensional indirect boundary element methods (for example, the fictitious load method and the displacement discontinuity method). It also provides an analysis of crack problems in elastostatic and elastodynamic fracture mechanics, and methods for evaluating weight functions for dynamic problems.