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Showing 1 to 20 of 55 for “"Fracture Strength"”.
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The Fracture Strength of Ceramic Brackets : A Comparative Study
… conditions and different ligation methods on the fracture strength of ceramic brackets and the yield strength of metal brackets.</p> <p>Ceramic brackets followed the Griffith model, which was used to interpret their fracture strength with respect to their surface condition. With surface damage …
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Quantitative Fracture Strength of Lithiated Tin Oxide Nanowires by In-Situ SEM Tensile Experiments
The quantitative fracture strength of lithiated and pristine tin oxide (SnO2) nanowires was gathered from in situ scanning electron microscope (SEM) mechanical tests using a micro electromechanical system (MEMS) uniaxial tensile testing device. Stress values were calculated from load and …
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Studies of structure cracking and fracture strength of E-glass fibres using acoustic emission.
… developed to permit the determination of the strength distribution of E-glass fibre strands containing as many as 4,000 filaments. This technique is novel in that it allows fast data acquisition and provides the accurate load, location and time of fracture of each filament. The design also …
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Effect of manganese and nickel on the cleavage fracture strength of ferritic weld metal
… were used to obtain values for the cleavage fracture strength. This was calculated by reference to slip line field theory from the fracture load at the test temperature where fracture was first coincident with general yielding. The commercial electrodes were first tested in the as welded …
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Fracture strength of commercial soda - lime - silica glass from a -100⁰C to 700⁰
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Metallurgy, 1962.
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The effect of simulated oral and clinical conditions on the fracture strength of ceramic bracket tie-wings
… oral and clinical conditions on the tie-wing fracture strength of a polycrystalline and a monocrystalline bracket. Fracture strength was measured for brackets as-received (control) and after 7- or 21-day exposure to phosphate buffered saline solution (PBS) with or without repetitive ligation. …
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Survival rate and fracture strength of maxillary incisors, restored with different kinds of full veneers : an in-vitro study
In this study, the survival rate and fracture strength of different kinds of ceramic full veneers, fabricated with a new experimental press ceramic (EPC), were evaluated after exposure to the artificial mouth. <br>Eighty, caries-free human maxillary central molars were used as abutments for the …
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Survival rate and fracture strength of endodontically treated crowned maxillary incisors with severe defects, restored with different post and core systems after exposure to the artificial mouth.
… 93.75 group 2 and 3, and 100 group 4. The mean fracture strengths and the standard deviations were as follows: 374.34 N (181.47) group 1, 429.36 N (150.16) group 2, 514.70 N (236.54) group 3, 516.34 N (139.76) group 4. The all ceramic post and core group is a reliable material for the …
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Fracture resistance of molars restored with different types of ceramic partial coverage restorations : an in-vitro study
In this study, the survival rate and fracture strength of ceramic inlays, different types of onlays and unprepared teeth were compared, after exposure to the artificial mouth. <br>Ninety-six caries-free human upper first molars were used for the experiment. The teeth were randomly divided into five …
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Mechanical characterisation of float and laminated glass
… affects its structural integrity and safety. The fracture strength of glass materials is highly sensitive to micro-flaws, which act as stress concentrators and initiate cracks [5]. For a given flaw density, as the volume increases, the number of flaws, and, in particular, the number of flaws of …
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Materials characterization and structural design of ceramic micro turbomachinery
… especially with regard to the material fracture strength. Strength test specimens must have similar length scales and be fabricated by the same processing route as the real structures. The data for fracture strength, fracture toughness, yield strength, and creep resistance of single …
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Factors affecting the fracture energy of a structural adhesive
A fracture investigation was conducted on a modified epoxy adhesive (Metlbond 1113-2). Initially various adhesive fracture strength and energy tests and the mechanisms of mechanical and chemical adhesion were discussed. A critical study was then made of the sensitivity of the strain energy release …
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Modeling Interfacial Slag Layer Phenomena in the Shell /Mold Gap in Continuous Casting of Steel
… When the shear stress exceeds the slag shear strength before the axial stress accumulates to the fracture strength, the slag could shear longitudinally inside the layers.
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Elastic properties and fracture behavior of graphite/polyimide composites at extreme temperatures
… cryogenic temperatures on the elastic moduli and fracture strengths of several Celion-6000/PMR-15 laminates was measured. Tests were run at -157,24 (room temperature), and 316°C (-250, 75, and 600°F). Both unnotched and notched laminates were tested. Several failure criteria, developed to predict …
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Processing, microstructure and mechanical properties of alumina platelet reinforced 3Y-TZP and mullite composites
… mechanical properties of the composites such as fracture strength, fracture toughness and high temperature microhardness as a function of platelet size and volume fractions were determined.
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Processing, characterization, and mechanical properties of beta silicon nitride whisker/silicon nitride matrix composites
… properties of the composites, primarily fracture strength and fracture toughness, were measured and compared to those of the unreinforced matrices.
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Residual Stress Effects on Power Slump and Wafer Breakage in GaAs MESFETs
… processing has been shown to both reduce the fracture strength and increase the residual stress in GaAs wafers, making them more susceptible to wafer breakage. Bare wafers are found to have higher fracture strength than passivated wafers. Bare wafers are also found to contain less residual …
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Role of segregation and precipitates on interfacial strengthening mechanisms in metal matrix composites when subjected to thermo-mechanical processing
… the reinforcement, leading to high stiffness and strength with a reduction in structural weight. The main objective of using a metal matrix composite system is to increase service temperature or improve specific mechanical properties of structural components by replacing existing superalloys.</p> …
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Structural heterogeneity in silk fibers and its effects on failure mechanics and supercontraction
… its crystalline phase, relates to its fracture mechanical properties: strength and toughness. Analytical fracture mechanical arguments are presented to illustrate the relation between fracture strength and heterogeneity in silk and other biopolymers. Nanoconfinement and flaw tolerance …
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A study of blister tests for film adhesion measurement and fracture efficiency of tests for adhesive bonds
A novel concept, the fracture efficiency, is proposed in this dissertation as a performance index of fracture specimen designs for adhesive bonds. Evaluated based on a simple quantity, the fracture efficiency parameter, the fracture efficiency represents how much crack driving force a certain …
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