Results 261 to 270 of about 44,040 (298)

Micro and Macro Crack Formation

International journal of fracture mechanics, 1965
The formation of cleavage microcracks with a length of the order of one grain diameter is considered to be the initial step in fracture. It is assumed that the stress concentration required for cleavage is supplied by thick slip or twin bands, and the critical width of these yield bands is calculated. For example, in iron with a grain radius of 10−2 cm,
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Micro-cracking of tooth structure.

American journal of dentistry, 2005
To determine if the cutting procedure utilized in producing a cavity preparation, i.e., a high speed dental handpiece or an Er:YAG laser may be a factor in initiating the formation of micro-cracks during or after preparation of the cavity and before and after placing and curing the dental composite.Class I occlusal and Class II MOD preparations were ...
Christina, Sehy, James L, Drummond
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On the sink strength and permeability of micro-cracked arrays

Proceedings of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences, 2003
Summary: The effective absorption coefficient (the sink strength or the trapping constant) \(\gamma\) of a statistically isotropic random array of penny-shaped cracks is considered. The cracks are treated as oblate spheroids with vanishing aspect ratio.
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Ultrasonic Evaluation of Ceramics With Micro-Cracks

Emerging Technology in Fluids, Structures, and Fluid Structure Interactions, 2003
Materials used in high-pressure vessels may be subjected to rapid temperature change, which may induce micro-cracks on the surface and into material. The growth of micro-cracks is detrimental to facility life. Chromium carbide (Cr3C2) has been proved to be a potential structural material for toughening alumina in biomedical and industrial applications ...
Shih-Jeh Wu, Ching-An Jeng, Chen-Ming Kuo   +2 more
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Micro-macro crack interaction in composites

Engineering Fracture Mechanics, 1994
Abstract The interaction of a macro-crack and a micro-crack is the subject of this study. The cracks considered are: matrix micro-crack (straight and kinked at 45°) interacting with matrix macro-cracks of different lengths, and a matrix micro-crack (straight and kinked at 45°) interacting with delamination macro-cracks of different lengths.
Vinay Dayal, Ilyas Mohammed
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Hydrogen in steel—the stability of micro-cracks

Acta Metallurgica, 1962
Abstract The stability of a wedge shaped microcrack under constant external stress and internal pressure is examined. Some modifications are found necessary in the original analysis of the stability under external stress only; these reinforce the conclusion that a crack formed under tension by the pile-up mechanism will grow unless damped by plastic ...
B.A Bilby, J Hewitt
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A continuum model of micro-cracks in concrete

Continuum Mechanics and Thermodynamics, 2009
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Bongué Boma, Malika, Brocato, Maurizio
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Miniaturized magneto-optical imaging sensor for crack and micro-crack detection

Optik, 2020
Abstract A highly-sensitive magneto-optical Faraday sensor was miniaturized, including Bi-substituted yttrium iron garnet (Bi: YIG) thin films. The magnetic field over the surface of the cracked steel was measured by using this sensor. The results demonstrated that this sensor could illustrate the micro-cracks on the surface and subsurface of the ...
H. Eftekhari, M.M. Tehranchi
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A Microstructural Model for Micro-Cracking in Piezoceramics

Key Engineering Materials, 2018
Piezoelectric ceramics are employed in several applications for their capability to couple mechanical and electrical fields, which can be advantageously exploited for the implementation of smart functionalities. The electromechanical coupling, which can be employed for fast accurate micro-positioning devices, makes such materials suitable for ...
Benedetti, Ivano, Gulizzi, Vincenzo, Milazzo, Alberto   +2 more
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Temperature-Dependent Micro-Crack Propagation

RPV Integrity and Fracture Mechanics, 2004
The crack-lattice trapping phenomenon introduce by R. Thomson et al[1] is studied for the conditions of the Frenkel-Kontrova-type experiment. By using a new method, which allows further model extension for a finite temperature case we are able to describe an equilibrium crack energetics for arbitrary externa conditions and ascertain the crack ...
Kazuhiro Kitamura, I. L. Maksimov
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