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Stress curves

For a monolayer film, the stress-strain curve from Eqs. (103) and (106) is plotted in Fig. 15. For small shear strains (or stress) the stress-strain curve is linear (Hookean limit). At larger strains the stress-strain curve is increasingly nonlinear, eventually reaching a maximum stress at the yield point defined by = dT Id oLx x) = 0 or equivalently by c (q x4) = 0- The stress = where is the (experimentally accessible) static friction force [138]. By plotting T /Tlx versus o-x/o x shear-stress curves for various loads T x can be mapped onto a universal master curve irrespective of the number of strata [148]. Thus, for stresses (or strains) lower than those at the yield point the substrate sticks to the confined film while it can slip across the surface of the film otherwise so that the yield point separates the sticking from the slipping regime. By comparison with Eq. (106) it is also clear that at the yield point oo. [Pg.53]

The resulting data can then be presented as a series of curves much like the isometric stress curves in Fig. 2-27. A relaxation modulus similar to the creep modulus can also be derived from the relaxation data. It has been shown that using the creep modulus calculated from creep curves can approximate the decrease in load from stress relaxation. [Pg.73]

The elastic stress curve in figure perfectly follows elastic strain [2]. This constant is the elastic modulus of the material. In this idealized example, this would be equal to Young s modulus. Here at this point of maximum stretch, the viscous stress is not a maximum, it is zero. This state is called Newton s law of viscosity, which states that, viscous stress is proportional to strain rate. Rubber has some properties of a liquid. At the point when the elastic band is fully stretched and is about to return, its velocity or strain rate is zero, and therefore its viscous stress is also zero. [Pg.784]

Figure 28.9 shows the total stress curve (a combination of the viscous and elastic), it is called viscoelastic curve. It is following, the elastic one, by a distance, equivalent to a certain number of degrees, known as delta, 8. [Pg.784]

The stress curve sharply increases when the steric component appears upon compression. The initial thickness of a deformed layer is equal to be half the distance Dq obtained by extrapolating the sharpest initial increase to stress zero. The value Do is 21 1 nm, which is close the thickness of two molecular layers (19.2 nm) of the a-helix brush, calculated using the CPK model and the orientation angles obtained by FTIR analysis. We have calculated the elastic compressibility modulus Y,... [Pg.12]

Metal from internal friction from velocity-stress curves... [Pg.85]

The stress at the interface was measured as a function of temperature and sliding velocity for the resin using the equipment shown in Fig. 4.11, and the data are shown in Fig. 12.33. The stress curve had two maximums the first peak was at the Tg of the resin at 150 °C, and the second peak occurred at a temperature of about 240 °C. In order to maximize solids conveying while maintaining a viable process, the optimal forwarding forces would occur at a barrel surface temperature near 240 °C, and the retarding forces at the screw surfaces would be minimized at temperatures less than about 120 °C. In order to maintain the high rate of this line and the inside barrel wall at a temperature near 240 °C, the first zone of the extruder needed to be maintained at a temperature of 310 °C. [Pg.586]

Slurry Viscosities. In addition to the yield stress, the characteristic shear stress-shear rate relation of the fuel slurry should be known since the shape of the shear rate-shear stress curve (consistency curve) is an indication of the gel characteristics. Low shear rate data (102 sec."1) are useful mainly in determining batch-to-batch reproducibility, while high shear rate data (104 to 106 sec."1) are required to assess the flow characteristics in engine hardware. [Pg.360]

Figure 8. Shear-stress curves for native and alkylated-reduced gliadin and glutenin solutions at low shear stresses (5)... Figure 8. Shear-stress curves for native and alkylated-reduced gliadin and glutenin solutions at low shear stresses (5)...
Fig. 4.5.11. Stress curves—elastic recovery for glazes with a high modulus of elasticity (1) and with a low modulus of elasticity (2). Fig. 4.5.11. Stress curves—elastic recovery for glazes with a high modulus of elasticity (1) and with a low modulus of elasticity (2).
Similar tests of sections deformed under the action of a Vickers indenter were conducted by Lawn et al. (1980) who used transmission and interference microscopy for this purpose. Tests with Si, Ge, SiC and A1203 crystals revealed a similar, spherical pattern of stress curves for sharp cracking and sharp indenter. Chandhri -et al. (1980) confirmed the test results of... [Pg.262]

The sample must have reached steady state before cessation of the test or the application of a second step. Steady state in a creep test is seen as a constant slope in the strain curve. A constant slope in the stress curve may also be seen in a stress relaxation test, but often the signal is lost in the noise. A material that is liquid-like in real time will need a test period of 5 to 10 min. A stress relaxation test is likely to be somewhat shorter than a creep test since the signal inevitably decays into the noise at some point. A creep test will last indefinitely but will probably reach steady state within an hour. For a material that is a solid in real time, all experiments should be longer as molecular motion is, by definition, slower. Viscoelastic materials will lie in between these extremes. Polymer melts can take 1 hr or more to respond in a creep test, but somewhat less time in a stress relaxation test. [Pg.1219]

A tangent line from the point (a, i n) - (0, —1) on the true stress curve hits this curve at that value of n where the engineering stress curve has its maximum value. This is called... [Pg.462]

The yield stress curve will be increased by crystallinity, but within certain limits the brittle strength will not be affected. Consequently the brittle temperature will increase with increasing crystallinity the material becomes more brittle. [Pg.469]

Samples for impact measurements are frequently provided with a notch. Such a notch will of course in principle not affect the brittle temperature, but it does affect the distribution of the applied force in the sample. Near the notch the stresses are triaxially distributed and a higher yield stress in the direction of the net force causes the "normal" yield stress in the sample near the notch. Accordingly, the yield stress curve will be increased and consequently the brittle temperature will apparently be shifted to higher values. [Pg.469]

The main experimental methodology used is to directly characterize the tensile properties of CNTs/polymer composites by conventional pull tests (e.g. with Instron tensile testers). Similarly, dynamic mechanical analysis (DMA) and thermal mechanical analysis (TMA) were also applied to investigate the tensile strength and tensile modulus. With these tensile tests, the ultimate tensile strength, tensile modulus and elongation to break of composites can be determined from the tensile strain-stress curve. [Pg.395]

Fig. 32. Comparison of the calculated [49] and measured [51, 52] yield stress. Curve I is for PPO/PS blends under uniaxial compression, and curve 2 for PPO/PS-pCIS blends under uniaxial tension... Fig. 32. Comparison of the calculated [49] and measured [51, 52] yield stress. Curve I is for PPO/PS blends under uniaxial compression, and curve 2 for PPO/PS-pCIS blends under uniaxial tension...
Tihe brittle-ductile transition of metals as reported by Orowan (I) is explained on the basis that brittle fracture occurs when the yield stress exceeds a critical value. This is based on the Ludwik-Davidenkov-Orowan hypothesis that brittle fracture and plastic flow are independent processes yielding separate curves as a function of temperature and strain rate. Therefore, the operative deformation process is the one occurring at the lower stress. The intersection of the brittle stress and yield stress curves therefore defines the brittle-ductile transition. [Pg.117]

Steady State Measurements Fig. 1 shows the shear rate-shear stress curves at various bentonite concentrations (calculated on the basis of the continuous phase) Hysteresis in the shear rate-shear stress curves was insignificant and the correlation between the ascending and descending curves was within experimental error. The results shown in Fig. 1 were therefore, the mean value of the ascending and descending curves. In the absence of any bentonite the suspension was Newtonian, whereas all suspensions containing bentonite at concentrations > 30 g dm were all pseudoplastic. This is illustrated from a plot of viscosity versus shear rate (Figure 2) which shows an exponential reduction of h with increase in shear rate. [Pg.33]

Two extrapolation methods were used to obtain the yield value, Tg, from the shear rate-shear stress curves. In the first method, the data were fitted to a Bingham model, ie. [Pg.33]

Figure 1, Shear rate - shear stress curves at various bentonite concentrations... Figure 1, Shear rate - shear stress curves at various bentonite concentrations...

See other pages where Stress curves is mentioned: [Pg.173]    [Pg.44]    [Pg.330]    [Pg.59]    [Pg.60]    [Pg.38]    [Pg.227]    [Pg.313]    [Pg.173]    [Pg.17]    [Pg.66]    [Pg.127]    [Pg.167]    [Pg.269]    [Pg.134]    [Pg.112]    [Pg.534]    [Pg.210]    [Pg.880]   
See also in sourсe #XX -- [ Pg.94 ]

See also in sourсe #XX -- [ Pg.267 , Pg.359 , Pg.361 , Pg.430 ]

See also in sourсe #XX -- [ Pg.146 , Pg.147 , Pg.167 ]




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Acrylic fibers stress-strain curve

Alumina stress-strain curve

Amorphous stress-strain curve

Approximation of the stress-strain curve

Axial stress, distribution curves

Block copolymers stress-strain curves

Block polymers stress-strain curves

Brittle polymers, stress-strain curve

Cellulose acetate tensile stress-strain curves

Collagen fibers stress-strain curves for

Collagen fibrils stress-strain curve

Compression stress-strain curves

Curve, stress relaxation

Curves, true stress-strain

Cyclic Stress-Strain Curve Determination

Cyclic stress-strain curves

Deformation stress-strain curves

Diamond stress curves

Ductile ceramics stress strain curves

Epoxy resins stress-strain curves

Fatigue testing cyclic stress-strain curve

Fibers stress-strain curves

Fibrils stress-strain curves, figure

GRAPHITE-EPOXY STRESS-STRAIN CURVES

Hexagonal crystals stress curves

High-density polyethylene stress-strain curves

Interfacial stress distribution curve

Isochronous stress-strain curve

Load-elongation curves yield stress

Master Curve for the Fatigue Strength at Zero Stress Ratio

Master Curve of Fatigue Strength for Zero Stress Ratio

Material properties uniaxial stress-strain curve

Materials science stress-strain curves

Mechanical property measurement stress-temperature curves

Mechanical property measurement stress-time curves

Mechanical stress-strain curve

Mechanical testing stress-strain curves

Mild steel stress-strain curve

Nano-silica stress-strain curves

Nonlinear responses, stress-strain curves

Phase separation stress-strain curves

Pipe pressure test stress-rupture curve

Poly stress-strain curves

Poly tensile stress-strain curves

Polycarbonate stress-strain curves

Polyethylene stress relaxation curve

Polyisobutylene stress relaxation curve

Polymerisation Stress-strain curve

Polypropylene stress relaxation curve

Polypropylene stress-strain curves

Polystyrenes stress-strain curve

Polyurethane Stress-strain curves

Polyurethane elastomers stress-strain curves

Polyvinyl chloride stress-strain curve

Pressure stress-strain curve

Quartz stress-strain curves

Quasi stress-strain curve

Refractory stress-strain curves

Rubber natural, stress-temperature curves

Sapphire stress-strain curves

Serrated Stress-Strain Curves

Shape-memory alloys stress-strain curve

Shear stress, distribution curves

Shear stress-strain curves

Silk fiber stress-strain curve

Soft tissues stress-strain curve

Stress concentration curve

Stress corrosion cracking curves

Stress curves Stretch

Stress durability curve

Stress relaxation master curve

Stress relaxation modulus curve

Stress vs. strain curves

Stress-Strain Curve of a Single Chain

Stress-deformation curve

Stress-elongation curves

Stress-extension/strain curves

Stress-log time curves

Stress-relaxation curve, viscoelastic behavior

Stress-stain curve

Stress-strain curve concentration

Stress-strain curve for fibers

Stress-strain curve rubbers

Stress-strain curve viscoelastic polymers

Stress-strain curve, quasi-static

Stress-strain curve, toughness

Stress-strain curve/data

Stress-strain curves

Stress-strain curves Considere construction

Stress-strain curves WLF equations

Stress-strain curves assessment of long-term behaviour

Stress-strain curves characteristic shape

Stress-strain curves composites

Stress-strain curves compressive loading

Stress-strain curves copolymer

Stress-strain curves elastic

Stress-strain curves elastic moduli

Stress-strain curves elasticity

Stress-strain curves elastomer

Stress-strain curves epoxies

Stress-strain curves for

Stress-strain curves for poly

Stress-strain curves for skin

Stress-strain curves for tendons

Stress-strain curves hydrogel

Stress-strain curves linear viscoelasticity

Stress-strain curves nanofiber mats

Stress-strain curves of fibers

Stress-strain curves of polymers

Stress-strain curves plastics mechanical behavior

Stress-strain curves polymer morphology

Stress-strain curves simulations

Stress-strain curves systems

Stress-strain curves temperature

Stress-strain curves tensile impact

Stress-strain curves tensile testing

Stress-strain curves uniaxial tensile loading

Stress-strain curves viscous

Stress-temperature curves

Stress-time curves

Stress-voltage curve

Stress/life curves

Subject stress- strain curves

TYPICAL STRESS-STRAIN CURVES

Temperature-dependent stress-strain curves

Tensile stress-strain curves

Tensile stress/strain curve for

Tensile testing, plastics stress—strain curves

Tensile testing, stress-strain curve from

Testing stress-strain curves

The Stress-Strain Curve

The Stress-Strain Curve at High Elongations

Velocity-stress curve

Viscoelasticity stress-strain curves

Viscosity-stress curves

Vulcanized stress/strain curves

Wall shear stress-flow characteristic curves and scale-up

Whisker stress-strain curve

Yield strain stress-temperature curves

Yield strain stress-time curves

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