DOE Material Science 1
... Solid matter is held together by forces originating between neighboring atoms or molecules. These forces arise because of differences in the electron clouds of atoms. In other words, the valence electrons, or those in the outer shell, of atoms determine their attraction for their neighbors. When phy ...
... Solid matter is held together by forces originating between neighboring atoms or molecules. These forces arise because of differences in the electron clouds of atoms. In other words, the valence electrons, or those in the outer shell, of atoms determine their attraction for their neighbors. When phy ...
The role of chain length and conformation in stress
... interaction between chain segments, the fracture energy levels off for very long chains. For PMMA a terminal value of G Ic of about 300 Jm−2 has been determined, which is several orders of magnitude smaller than the fracture energy of a mono-crystal, where primary bonds are loaded and broken [5]. (I ...
... interaction between chain segments, the fracture energy levels off for very long chains. For PMMA a terminal value of G Ic of about 300 Jm−2 has been determined, which is several orders of magnitude smaller than the fracture energy of a mono-crystal, where primary bonds are loaded and broken [5]. (I ...
numerical modelling and design of alfc shield loaded by 20 mm fsp
... nonlinear elastic-plastic range taking into account high strain rates (Johnson–Cook model). The plates are exposed to large displacements and large plastic deformations. 2) The 99.7% Al2O3 ceramic is treated as the nonlinear elastic-short material taking into account high strain rates (JH-2 Johnson– ...
... nonlinear elastic-plastic range taking into account high strain rates (Johnson–Cook model). The plates are exposed to large displacements and large plastic deformations. 2) The 99.7% Al2O3 ceramic is treated as the nonlinear elastic-short material taking into account high strain rates (JH-2 Johnson– ...
Two Interpretations of Rigidity in Rigid Body Collisions
... Modeling collisions, the brief strong contact interactions of solid bodies, is of interest both for applications including robotics and general multibody dynamics simulations and to help complete classical mechanics, which does not include a settled approach to constitutive laws for contact. In dyna ...
... Modeling collisions, the brief strong contact interactions of solid bodies, is of interest both for applications including robotics and general multibody dynamics simulations and to help complete classical mechanics, which does not include a settled approach to constitutive laws for contact. In dyna ...
lectures 9 polyphase structures lecture plan
... In areas of only two phases of folding, the crenulation foliation S2, (approximately axial planar to the second phase of folds) will be fairly constant in orientation, whereas the orientation of L2 in S1 will vary according to the orientation of S1 within the first phase fold structures (i.e it will ...
... In areas of only two phases of folding, the crenulation foliation S2, (approximately axial planar to the second phase of folds) will be fairly constant in orientation, whereas the orientation of L2 in S1 will vary according to the orientation of S1 within the first phase fold structures (i.e it will ...
Prediction of stress-strain relationships in low
... Becker and Foppl (7) pointed out that the usual assumption in strength of materials of solids being elastic is not true. They referred to fatigue failures of machine parts at stresses below the usual proportional limit as examples of the failure of the assumption. They also pointed out that vibratio ...
... Becker and Foppl (7) pointed out that the usual assumption in strength of materials of solids being elastic is not true. They referred to fatigue failures of machine parts at stresses below the usual proportional limit as examples of the failure of the assumption. They also pointed out that vibratio ...
006_Material properties - SAFIR manual - UEE
... formulation, instead of the specific heat, makes the software much more stable in cases where the specific heat curve shows sudden and severe variations as is the case, for example, in gypsum or with the evaporation of moisture. Parameters to be introduced for all materials are the coefficient of co ...
... formulation, instead of the specific heat, makes the software much more stable in cases where the specific heat curve shows sudden and severe variations as is the case, for example, in gypsum or with the evaporation of moisture. Parameters to be introduced for all materials are the coefficient of co ...
Elastic-Plastic-Creep Analyses of Brazed Carbon
... are not more significant is that the total strains developed in the OFHC tube are about the same whether achieved by an elastic-plastic path or a combined elastic- plastic-creep path. This is due to the low yield stress and nearly flat-top stressstrain curve of annealed OFHC. It is theorized that it ...
... are not more significant is that the total strains developed in the OFHC tube are about the same whether achieved by an elastic-plastic path or a combined elastic- plastic-creep path. This is due to the low yield stress and nearly flat-top stressstrain curve of annealed OFHC. It is theorized that it ...
p181B 01 09 2006 zhang
... Fig. 2. (a) Temperature history in a thermal-cycling test. (b) Optical micrograph of a fractured die surface after 1000 temperature cycles. (c) SEM micrograph with a FIB cut. the edges and corners of the die. During a thermal-cycling test, the high-end temperature (1500C) is lower than the curing te ...
... Fig. 2. (a) Temperature history in a thermal-cycling test. (b) Optical micrograph of a fractured die surface after 1000 temperature cycles. (c) SEM micrograph with a FIB cut. the edges and corners of the die. During a thermal-cycling test, the high-end temperature (1500C) is lower than the curing te ...
Brittle fracture - Flaney Associates
... simplest form, fracture can be described as a single body separated into pieces by an imposed stress. For engineering materials there are two possible modes of fracture, ductile and brittle. In general, the main difference between brittle and ductile fracture can be attributed to the amount of plast ...
... simplest form, fracture can be described as a single body separated into pieces by an imposed stress. For engineering materials there are two possible modes of fracture, ductile and brittle. In general, the main difference between brittle and ductile fracture can be attributed to the amount of plast ...
Dislocations
... stress at which a crack will propagate and eventually fail The stress at which fracture occurs in a material is termed fracture strength For a brittle elastic solid this strength is estimated to be around E/10, E being the modulus of elasticity This strength is a function of the cohesive forces b ...
... stress at which a crack will propagate and eventually fail The stress at which fracture occurs in a material is termed fracture strength For a brittle elastic solid this strength is estimated to be around E/10, E being the modulus of elasticity This strength is a function of the cohesive forces b ...
Two Interpretations of Rigidity in Rigid Body Collisions
... In this paper, we only discuss single-point collisions although the ideas are relevan 1.points collisions at multiple The material contact point on one body is the C where pointcontact is rst made. On the other hand, when paying attention to the motion of a body overall a reference R , contact which ...
... In this paper, we only discuss single-point collisions although the ideas are relevan 1.points collisions at multiple The material contact point on one body is the C where pointcontact is rst made. On the other hand, when paying attention to the motion of a body overall a reference R , contact which ...
Characterization of a High Strain Composite Material
... springs provides the energy that deploys the structure, but when the structure is folded the curvature changes in the tape springs have to be limited to the elastic range. A third approach is to use a foldable composite material in which the matrix either softens above a certain temperature (memory ...
... springs provides the energy that deploys the structure, but when the structure is folded the curvature changes in the tape springs have to be limited to the elastic range. A third approach is to use a foldable composite material in which the matrix either softens above a certain temperature (memory ...
Traveling Washer in Two Dimensions
... the direction, 53o NW, north of west. You could have specified the direction as 37o WN west of north, although this is not as common a form as measuring from the horizontal axis. Notice that the vector has the same direction with respect to the rectangular coordinate system. It is often easier to me ...
... the direction, 53o NW, north of west. You could have specified the direction as 37o WN west of north, although this is not as common a form as measuring from the horizontal axis. Notice that the vector has the same direction with respect to the rectangular coordinate system. It is often easier to me ...
Chapter 7 Non-linear Seismic Response of Structures
... Normally, it is not possible to have the scenario that at time, ti+1, the spring force is just equal to the yield force. However, this can be archived by reducing the time interval of the computation. Once the system enters into the plastic state, it continues to remain in that state until the incre ...
... Normally, it is not possible to have the scenario that at time, ti+1, the spring force is just equal to the yield force. However, this can be archived by reducing the time interval of the computation. Once the system enters into the plastic state, it continues to remain in that state until the incre ...
3-D Pushover Analysis for Damage Assessment of Buildings
... building. Based on the capacity curve, a target displacement which is an estimate of the displacement that the design earthquake will produce on the building is determined. The extent of damage experienced by the building at this target displacement is considered representative of the damage experie ...
... building. Based on the capacity curve, a target displacement which is an estimate of the displacement that the design earthquake will produce on the building is determined. The extent of damage experienced by the building at this target displacement is considered representative of the damage experie ...
INDENTATION PRESSURE OF A SMOOTH CIRCULAR PUNCH*
... after the field constructed by Hill [3] for the two dimensional punch. Due to symmetry this field is most easily applied to a circular punch. For other cross-sections the general formulation given in Sec. 2 would involve considerable labour and indeed might not yield the sharpest upper bound. For th ...
... after the field constructed by Hill [3] for the two dimensional punch. Due to symmetry this field is most easily applied to a circular punch. For other cross-sections the general formulation given in Sec. 2 would involve considerable labour and indeed might not yield the sharpest upper bound. For th ...
Quasistatic Deformation and Failure Modes of Composite Square Honeycombs
... The outline of the paper is as follows. First the composite sheet materials are described along with the route for fabricating the square-honeycombs cores from these materials. Second, the measured compressive and shear responses of the cores are detailed along with the observed failure modes. Analy ...
... The outline of the paper is as follows. First the composite sheet materials are described along with the route for fabricating the square-honeycombs cores from these materials. Second, the measured compressive and shear responses of the cores are detailed along with the observed failure modes. Analy ...
Chapter 15 - College of Engineering WordPress
... Processing of Polymers ISSUES TO ADDRESS... • What are the tensile properties of polymers and how are they affected by basic microstructural features? • Hardening, anisotropy, and annealing in polymers. • How does the elevated temperature mechanical response of polymers compare to ceramics and metal ...
... Processing of Polymers ISSUES TO ADDRESS... • What are the tensile properties of polymers and how are they affected by basic microstructural features? • Hardening, anisotropy, and annealing in polymers. • How does the elevated temperature mechanical response of polymers compare to ceramics and metal ...
Dyadic Tensor Notation
... scalar of rank zero. Tensors of higher rank can also be dened. For example a tensor of rank four, Qijkl acts on a rank two tensor to give another rank two tensor, Bij = Qijkl Akl (with summation over repeated indices). For tensors higher than rank two, dyadic notation becomes extremely cumbersome a ...
... scalar of rank zero. Tensors of higher rank can also be dened. For example a tensor of rank four, Qijkl acts on a rank two tensor to give another rank two tensor, Bij = Qijkl Akl (with summation over repeated indices). For tensors higher than rank two, dyadic notation becomes extremely cumbersome a ...
Lecture #19 Creep in Metals: - References:
... Creep is the tendency of a solid material to slowly deform permanently under the influence of stresses. It occurs as a result of long term exposure to levels of stress that ...
... Creep is the tendency of a solid material to slowly deform permanently under the influence of stresses. It occurs as a result of long term exposure to levels of stress that ...
Glossary of Biomechanical Terms, Concepts, and Units
... The tangential force acting between two bodies in contact that opposes motion or impending motion. If the two bodies are at rest, then the frictional forces are called static friction. If there is relative motion between the two bodies, then the forces acting between the surfaces are called kinetic ...
... The tangential force acting between two bodies in contact that opposes motion or impending motion. If the two bodies are at rest, then the frictional forces are called static friction. If there is relative motion between the two bodies, then the forces acting between the surfaces are called kinetic ...
Analysis for Pull-in Voltage Variations of Fixed–Fixed Beam - I-asem
... deformation and pull-in voltage is studied by changing various parameters, such as applied current, geometric length, and material of the fixed–fixed beam. The commercial software COMSOL is used to determine the pull-in voltage when the variables changed. Therefore, in this work we will make the des ...
... deformation and pull-in voltage is studied by changing various parameters, such as applied current, geometric length, and material of the fixed–fixed beam. The commercial software COMSOL is used to determine the pull-in voltage when the variables changed. Therefore, in this work we will make the des ...
Stress
... In fluids at rest pressure is the only contact force. For solids at rest or in motion, and for viscous fluids in motion, this simple picture is no longer valid. Besides pressure-like forces acting along the normal to a contact surface, there may also be shearing forces acting in any tangential direc ...
... In fluids at rest pressure is the only contact force. For solids at rest or in motion, and for viscous fluids in motion, this simple picture is no longer valid. Besides pressure-like forces acting along the normal to a contact surface, there may also be shearing forces acting in any tangential direc ...
ElaStic: A universal tool for calculating elastic constants from first
... The computed energies/stresses are fitted as polynomial functions of the applied strain in order to get derivatives at zero strain. The knowledge of these derivatives allows for the determination of all independent components of the elastic tensor. In this context, the accuracy of the elastic consta ...
... The computed energies/stresses are fitted as polynomial functions of the applied strain in order to get derivatives at zero strain. The knowledge of these derivatives allows for the determination of all independent components of the elastic tensor. In this context, the accuracy of the elastic consta ...
Deformation (mechanics)
Deformation in continuum mechanics is the transformation of a body from a reference configuration to a current configuration. A configuration is a set containing the positions of all particles of the body.A deformation may be caused by external loads, body forces (such as gravity or electromagnetic forces), or changes in temperature, moisture content, or chemical reactions, etc.Strain is a description of deformation in terms of relative displacement of particles in the body that excludes rigid-body motions. Different equivalent choices may be made for the expression of a strain field depending on whether it is defined with respect to the initial or the final configuration of the body and on whether the metric tensor or its dual is considered.In a continuous body, a deformation field results from a stress field induced by applied forces or is due to changes in the temperature field inside the body. The relation between stresses and induced strains is expressed by constitutive equations, e.g., Hooke's law for linear elastic materials. Deformations which are recovered after the stress field has been removed are called elastic deformations. In this case, the continuum completely recovers its original configuration. On the other hand, irreversible deformations remain even after stresses have been removed. One type of irreversible deformation is plastic deformation, which occurs in material bodies after stresses have attained a certain threshold value known as the elastic limit or yield stress, and are the result of slip, or dislocation mechanisms at the atomic level. Another type of irreversible deformation is viscous deformation, which is the irreversible part of viscoelastic deformation.In the case of elastic deformations, the response function linking strain to the deforming stress is the compliance tensor of the material.