Elastic and Inelastic Shock Compression of Diamond and Other
... strength is lower and, when exceeded, the release of energy is smaller; also, the formation of thermal heterogeneities is inhibited by larger thermal conductivity. In this case, deformation is thought to occur homogenously (plastically) by dislocation and slip on the microscopic scale, and strength ...
... strength is lower and, when exceeded, the release of energy is smaller; also, the formation of thermal heterogeneities is inhibited by larger thermal conductivity. In this case, deformation is thought to occur homogenously (plastically) by dislocation and slip on the microscopic scale, and strength ...
The impact behaviour of silk cocoons
... nonwoven cocoon categories in order to investigate their failure mechanisms. Bombyx mori cocoons have high porosity: the inter-fibre bonding breaks gradually with the increasing strain, leading to a reducing modulus; the stress drops when the breakage of the structure reaches a percolation point, th ...
... nonwoven cocoon categories in order to investigate their failure mechanisms. Bombyx mori cocoons have high porosity: the inter-fibre bonding breaks gradually with the increasing strain, leading to a reducing modulus; the stress drops when the breakage of the structure reaches a percolation point, th ...
Structure and Mechanical Properties of Fe-Mn Alloys
... Materials for automobile applications need both the high strength and good ductility. A combination of these beneficial mechanical properties requires sustained high strain hardening rate throughout the course of plasticity. Fe-Mn alloys are a good example of demonstrating such exceptional mechanical ...
... Materials for automobile applications need both the high strength and good ductility. A combination of these beneficial mechanical properties requires sustained high strain hardening rate throughout the course of plasticity. Fe-Mn alloys are a good example of demonstrating such exceptional mechanical ...
Stress relaxation behaviour in compression and some other
... material which results from the process of polymerisation and usually taken as family name for material that have long chain molecules. The term plastic is applied when additives are present in polymer (1). A polymer may be defined as a large molecule constructed from many smaller structural units c ...
... material which results from the process of polymerisation and usually taken as family name for material that have long chain molecules. The term plastic is applied when additives are present in polymer (1). A polymer may be defined as a large molecule constructed from many smaller structural units c ...
FATIGUE LIFE OF GRAPHITE/EPOXY LAMINATES SUBJECTED TO
... _ t and `t are a function of the material only, being independent of the stress range adopted, when RGFRPs failing in tension are considered. Later, similar results were presented in [14] and [17], where it was also shown that the model could be successfully applied to the prediction of the fatigue ...
... _ t and `t are a function of the material only, being independent of the stress range adopted, when RGFRPs failing in tension are considered. Later, similar results were presented in [14] and [17], where it was also shown that the model could be successfully applied to the prediction of the fatigue ...
Mechanical Properties of Pedal Mucus and Their Consequences for
... the yield strength increasing as the rate of deformation increases. The mucus can 'heal' if left undeformed, its strength increasing with time. When dehydrated the mucus strength and stiffness increase substantially. These properties can be used to calculate the maximum speed of crawling and the max ...
... the yield strength increasing as the rate of deformation increases. The mucus can 'heal' if left undeformed, its strength increasing with time. When dehydrated the mucus strength and stiffness increase substantially. These properties can be used to calculate the maximum speed of crawling and the max ...
high strain rate behaviour of woven composite
... The thesis centres on the dynamic behaviour of woven composite materials. The increase in the use of these materials in the aerospace industry demands a reliable constitutive damage model to predict their response under high strain rate loading. The current available models do not include rate effec ...
... The thesis centres on the dynamic behaviour of woven composite materials. The increase in the use of these materials in the aerospace industry demands a reliable constitutive damage model to predict their response under high strain rate loading. The current available models do not include rate effec ...
Acta Materialia_60_16_2012
... In addition to this body of largely experimental work, there have been significant contributions from the modelling community. Recently, Kumar and colleagues [23] have proposed a 2D dislocation dynamics (DD) model which extends previous DD based work, assuming that the grain boundary is impenetrable ...
... In addition to this body of largely experimental work, there have been significant contributions from the modelling community. Recently, Kumar and colleagues [23] have proposed a 2D dislocation dynamics (DD) model which extends previous DD based work, assuming that the grain boundary is impenetrable ...
Biomimetic design of materials and biomaterials inspired by the
... between peptide chains and the inorganic fraction, and that this association is mainly established through amino acids containing carboxylic groups (Metzler et al. 2008). A broad discussion on the properties of such molluscan shell protein was reviewed earlier (Marin et al. 2008). Different models f ...
... between peptide chains and the inorganic fraction, and that this association is mainly established through amino acids containing carboxylic groups (Metzler et al. 2008). A broad discussion on the properties of such molluscan shell protein was reviewed earlier (Marin et al. 2008). Different models f ...
Determination of shear strength of unidirectional composite
... a combined stress-failure criterion. There is currently no ASTM standard for the 10 o-axis test speci®cally, although ASTM D 3039-76 is a standard test method for o-axis tests on composite materials in general. Pindera and Herakovich [20] examined the errors in the measured values of elastic prop ...
... a combined stress-failure criterion. There is currently no ASTM standard for the 10 o-axis test speci®cally, although ASTM D 3039-76 is a standard test method for o-axis tests on composite materials in general. Pindera and Herakovich [20] examined the errors in the measured values of elastic prop ...
Failure modes of composite sandwich beams
... In the case when shear is present in addition to bending, the influence of the transverse shear modulus of the core, Gc13 , must be taken into account. An early expression given by Hoff and Mautner [7] has the form σcr = c (Ef 1 Ec3 Gc13 )1/3 ...
... In the case when shear is present in addition to bending, the influence of the transverse shear modulus of the core, Gc13 , must be taken into account. An early expression given by Hoff and Mautner [7] has the form σcr = c (Ef 1 Ec3 Gc13 )1/3 ...
Dislocation density evolution upon plastic deformation of Al-Pd
... by two orders of magnitude between the deformations at T ˆ 695 and 8208 C is found. Figure 3 (a) shows a typical bright-® eld electron micrograph of the sample deformed at 7308 C by " plast ˆ 5:2%, which shows the highest deformation-induced dislocation density. Figures 3 (b) and (c) show typical ex ...
... by two orders of magnitude between the deformations at T ˆ 695 and 8208 C is found. Figure 3 (a) shows a typical bright-® eld electron micrograph of the sample deformed at 7308 C by " plast ˆ 5:2%, which shows the highest deformation-induced dislocation density. Figures 3 (b) and (c) show typical ex ...
On small deformation interfacial debonding in composite materials
... separation, n , in terms of the macroscopic stress, . The main idea of this method is to relate the microscopic stress to the average stress in the matrix, instead of the macroscopic stress, in the RVE.30–32 As schematically illustrated in Figure 3, following the Mori– Tanaka approach, we consi ...
... separation, n , in terms of the macroscopic stress, . The main idea of this method is to relate the microscopic stress to the average stress in the matrix, instead of the macroscopic stress, in the RVE.30–32 As schematically illustrated in Figure 3, following the Mori– Tanaka approach, we consi ...
Short-time Dynamics of Frictional Strength in Dry Friction
... approximately 0.2μm at measurement frequencies of up to 1MHz. The location X was varied between experiments over the range X=10-70mm. Measurement of the real contact area, A(x,t) along the interface is described, schematically, in Figure 1a. A more detailed description of this measurement technique ...
... approximately 0.2μm at measurement frequencies of up to 1MHz. The location X was varied between experiments over the range X=10-70mm. Measurement of the real contact area, A(x,t) along the interface is described, schematically, in Figure 1a. A more detailed description of this measurement technique ...
Elastic response of cubic crystals to biaxial strain
... strain, however, rather thick overlayers can be grown before an instability occurs. In this case, most of the strain energy is stored in regions of the overlayer that are already bulklike, and can be estimated by studying biaxial deformations of bulk materials. In the region near the interface, the ...
... strain, however, rather thick overlayers can be grown before an instability occurs. In this case, most of the strain energy is stored in regions of the overlayer that are already bulklike, and can be estimated by studying biaxial deformations of bulk materials. In the region near the interface, the ...
Quasistatic Deformation and Failure Modes of Composite Square Honeycombs
... It is clear that topologically structuring composite materials shows promise for filling gaps in the strength versus density map of all known materials. The aim of the present study is to begin to investigate the expansion of the strength – density material space at low densities by using carbon fib ...
... It is clear that topologically structuring composite materials shows promise for filling gaps in the strength versus density map of all known materials. The aim of the present study is to begin to investigate the expansion of the strength – density material space at low densities by using carbon fib ...
structural implications of ultra-high performance fibre
... obtained from a developed finite element model. Using theoretical results and experimental data it is demonstrated that pre-peak behaviour and bending strength are mainly governed by multimicrocracking. The propagation of the macrocrack provides only a minor additional contribution to bending streng ...
... obtained from a developed finite element model. Using theoretical results and experimental data it is demonstrated that pre-peak behaviour and bending strength are mainly governed by multimicrocracking. The propagation of the macrocrack provides only a minor additional contribution to bending streng ...
Strain state in silicon structures for microprocessor technology M.
... The stress σ in the SiGe films is obtained via Hooke’s law: ...
... The stress σ in the SiGe films is obtained via Hooke’s law: ...
Anisotropy of Elastic Behavior
... properties for different directions are so large that one can not assume isotropic behavior - Anisotropic. • There is need to discuss Hooke’s Law for anisotropic cases in general. This can then be reduced to isotropic cases - material property (e.g., elastic constant) is the same in all directions. ...
... properties for different directions are so large that one can not assume isotropic behavior - Anisotropic. • There is need to discuss Hooke’s Law for anisotropic cases in general. This can then be reduced to isotropic cases - material property (e.g., elastic constant) is the same in all directions. ...
Influence of the cutting regime on the residual stresses generated by
... geometric distortions of a component/structure, especially those subjected to alternating service loads and/or corrosive environments. It arises from the elastic response of material to inhomogeneous distribution of non-elastic strains, e.g., precipitation, phase transformation, thermal expansion, e ...
... geometric distortions of a component/structure, especially those subjected to alternating service loads and/or corrosive environments. It arises from the elastic response of material to inhomogeneous distribution of non-elastic strains, e.g., precipitation, phase transformation, thermal expansion, e ...
ElaStic: A universal tool for calculating elastic constants from first
... Elastic properties play a key role in materials science and technology. The elastic tensors at any order are defined by the Taylor expansion of the elastic energy or stress in terms of the applied strain. In this paper, we present ElaStic, a tool which is able to calculate the full second-order elas ...
... Elastic properties play a key role in materials science and technology. The elastic tensors at any order are defined by the Taylor expansion of the elastic energy or stress in terms of the applied strain. In this paper, we present ElaStic, a tool which is able to calculate the full second-order elas ...
Analysis of process-induced residual stresses in tape placement
... fibers, being themselves anisotropic, contribute to this effect. The other factor is the temperature gradients induced during the cooling process. This is because of the fact that, when different regions of the composite experience different temperature histories and stiffness properties of the mate ...
... fibers, being themselves anisotropic, contribute to this effect. The other factor is the temperature gradients induced during the cooling process. This is because of the fact that, when different regions of the composite experience different temperature histories and stiffness properties of the mate ...
THE EFFECT OF CRYSTALLOGRAPHIC ORIENTATION ON
... Figure 2.9: Variation of the elastic modulus around the (011) crystal face of silicon. The elastic modulus in the [110] and [111] directions are 170 GPa and 190 GPa, respectively. The [111] direction is at an angle of 54.74° from the [100] direction. ................................................. ...
... Figure 2.9: Variation of the elastic modulus around the (011) crystal face of silicon. The elastic modulus in the [110] and [111] directions are 170 GPa and 190 GPa, respectively. The [111] direction is at an angle of 54.74° from the [100] direction. ................................................. ...
Fluid reservoirs in the crust and mechanical coupling between the... lower crust Bruce E Hobbs , Alison Ord
... pressure gradient alternates between approximately hydrostatic and approximately lithostatic (see Hunt, 1990). In the absence of a non-hydrostatic stress field, over a specific column of rock, the mean pore pressure and the mean pore pressure gradient must be lithostatic. This follows from the fact ...
... pressure gradient alternates between approximately hydrostatic and approximately lithostatic (see Hunt, 1990). In the absence of a non-hydrostatic stress field, over a specific column of rock, the mean pore pressure and the mean pore pressure gradient must be lithostatic. This follows from the fact ...
Lecture #19 Creep in Metals: - References:
... - Age hardened alloys will overage by particle coarsening and lose strength. - Oxidation and intergranular penetration. Different tests may be required to evaluate high temperature properties. These might include the following:(i) High Temperature Tensile Test: Similar to a short term room temperatu ...
... - Age hardened alloys will overage by particle coarsening and lose strength. - Oxidation and intergranular penetration. Different tests may be required to evaluate high temperature properties. These might include the following:(i) High Temperature Tensile Test: Similar to a short term room temperatu ...
Fracture mechanics
Fracture mechanics is the field of mechanics concerned with the study of the propagation of cracks in materials. It uses methods of analytical solid mechanics to calculate the driving force on a crack and those of experimental solid mechanics to characterize the material's resistance to fracture.In modern materials science, fracture mechanics is an important tool in improving the mechanical performance of mechanical components. It applies the physics of stress and strain, in particular the theories of elasticity and plasticity, to the microscopic crystallographic defects found in real materials in order to predict the macroscopic mechanical failure of bodies. Fractography is widely used with fracture mechanics to understand the causes of failures and also verify the theoretical failure predictions with real life failures. The prediction of crack growth is at the heart of the damage tolerance discipline.There are three ways of applying a force to enable a crack to propagate:Mode I fracture – Opening mode (a tensile stress normal to the plane of the crack),Mode II fracture – Sliding mode (a shear stress acting parallel to the plane of the crack and perpendicular to the crack front), andMode III fracture – Tearing mode (a shear stress acting parallel to the plane of the crack and parallel to the crack front).