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Showing 1 to 20 of 54 for “"Strain Energy Release Rate"”.
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The constrained blister - a nearly constant strain energy release rate test for adhesives
… of the blister test permitting nearly constant strain energy release rate testing of adhesive bonds. The work consisted of three parts; (1) development of the testing technique to evaluate strain energy release rate and to record the time dependent nature of the fracture process, (2) numerical …
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The development of the peninsula blister fracture test for adhesively bonded joints
… geometry benefits from both a constant strain energy release rate over the major portion of the debond length and a high strain energy release rate at any given pressure. Applications of this technique to several adhesion systems were conducted. Although some of these systems haven't …
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Experimental and Numerical Investigations on the Durability and Fracture Mechanics of the Bonded Systems for Microelectronics Application
… interface was measured as a function of applied strain energy release rate, G, and temperature using a wedge test geometry. The specimens consist of two glass plates bonded with a thin layer of proprietary epoxy adhesive. The crack fronts along the epoxy/glass interfaces were measured using an …
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Investigation of the Effects of Geometry on the Efficiency of the Double Lap Joint of Unidirectional Fiberglass Composites
… at instability and the corresponding critical strain energy release rate are independent of initial crack length in the range of crack length investigated. The critical strain energy release rate in Mode II is roughly six times higher for the elliptical geometry than for the rectangular.</p>
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Fracture Characteristics of Concretes and Cement-Stabilized Soil
… the stress intensity factor K approach and the strain energy release rate & approach. Both experimental and numerical methods are applied to determine the fracture toughness (K JT ) and results are compared on a range of specimen geometries. The numerical work was carried out on 100mm …
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Piezo-induced fatigue of solder joints
… results are derived for the plastic shear strain at the free edges of such a specimen using a shear lag model. Results are also presented for the strain energy release rate for steady state crack growth. Experimental results and observations are presented for the damage processes in …
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Environmental Influence on the Bond Between a Polymer Concrete Overlay and an Aluminum Substrate
… a polymer concrete overlay and an aluminum substrate. The purpose of this investigation is to evaluate the bond durability between the overlay and the aluminum substrate after conditioning specimens in various temperature and humidity conditions. The average critical strain energy release rate, …
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The effect of cooling rate on toughness and crystallinity in poly(ether ketone ketone) (PEKK)/G30-500 composites
… were used to investigate the effect of cooling rate on crystallinity. A fifth panel was used to investigate the effect of annealing the composite after completion of the standard fabrication process. The sixth panel was used to investigate changes in toughness due to manufacturing towpreg with …
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Time- and Temperature-Dependence of Fracture Energies Attributed to Copper/Epoxy Bonds
… to related, high-speed failure events. Work (or energy) is required to create new surface area—with associated dissipation events—during fracture, and this energy (for a given material system) is dependent on the speed of crack propagation, the locus of failure, and the temperature of the bond …
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The effect of sintering and CMAS on the stability of plasma-sprayed zirconia thermal barrier coatings
… thermal expansion coefficient and high in-plane strain tolerance. However, as turbine entry temperatures are raised, the performance of 7YSZ coatings will be increasingly affected by sintering and environmental contamination, by calcia-magnesia-alumina-silica (CMAS) deposits. The effect of …
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On a generalized laminate theory with application to bending, vibration, and delamination buckling in composite laminates
In this study, a computational model for accurate analysis of composite laminates and laminates with including delaminated interfaces is developed. An accurate prediction of stress distributions, including interlaminar stresses, is obtained by using the Generalized Laminate Plate Theory of Reddy in …
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A combined experimental and stochastic finite element analysis methodology for the probabilistic fracture behavior of composite laminates
… element analysis methodology that can incorporate the material property variabilities and based on these, predict the stochastic characteristics of the Stress Intensity Factor (SIF) and the Strain Energy Release Rate (G) of composite laminates, is developed. Using this methodology, the …
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Mechanics of fatigue damage in titanium-graphite hybrid laminates
… TiGr specimens with facesheet seams. The growth rate of delamination from facesheet seams is related via a power law to the applied strain energy release rate. It is shown that elevated temperatures significantly increase the growth rate of facesheet delamination. The facesheet crack growth …
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The single fiber pull-out test: a study of fiber/matrix interactions
… first time, the load versus extension trace generated by such experiments was thoroughly interpreted and mathematically modeled. To this end, the embedding resin was physically characterized through the determination of the glass transition temperature, T<sub>g</sub>, the relative change in …
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Mechanical Behavior of Adhesive joints Subjected To Thermal Cycling
… polymeric materials bonded to stiff elastic substrates was investigated using numerical techniques, including finite element methods. The work explored the relationship between a cyclic temperature environment, temperature-dependent viscoelastic behavior of polymers, and thermal stresses induced …
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An Evaluation of the Durability of Polymer Concrete Bonds to Aluminum Bridge Decks
… varied from none to twelve months. The critical strain energy release rate (Gc) of the bond was determined using a compliance technique. In spite of considerable scatter in the data, the results suggested that the interfacial bond toughness had been degraded by exposure conditions. The aging …
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Fiber Orientation Effects on the Fracture and Flexural Toughness of Extruded Fiber Reinforced Concrete for Additive Manufacturing
… crack tip opening displacement (CTODc), the strain energy release rate (GIC), and the total fracture energy (GF). The results show that enhanced ductility and post-peak behavior are achieved in concrete to which fibers have been added, as has been demonstrated in other studies, although this …
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Mechanics aspects of water thermocompression bonding
… typical geometries and process conditions. The strain energy release rate associated with the elastic deformation required to overcome wafer bow is calculated. A contact yield criterion is used to examine the pressure and temperature conditions required to flatten surface roughness asperities in …
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An Improved Method for the Fracture Cleavage Testing of Adhesively-Bonded Wood
… procedure for adhesively-bonded wood, and demonstrates the sensitivity of this approach. The two significant improvements were: 1) the use of the flat double cantilever beam (DCB) geometry, which has been uncommon for wood and 2) the application of an established and powerful data analysis using a …
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Durability of Adhesive Joints Subjected to Environemntal Stress
… integrity of an adhesive interface with a substrate. Therefore such disruptions can significantly reduce the lifetime and durability of an adhesive joint.1-4 In this research, the durability of certain epoxy adhesive joints and coatings were characterized using a fracture mechanics approach and …
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