Yield Mode Transition at Constant Strain Rate Shear in Amorphous PET

Constant strain-rate plastic straining followed by creep tests were conducted to investigate the effect of prior plastic straining on the subsequent creep behavior of 304 stainless steel at room temperature. The effects of plastic strain and plastic strain-rate were delineated by a specially designed test procedure, and it is found that both factors have a strong influence on the subsequent creep deformation. A creep model combining the two factors is then developed. The predictions of the model are in good agreement with the test results.

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The Effects of Physical Ageing and of Prior Immersion on the Esc Behaviour of Polycarbonate in Ethanol

MRS Proceedings ◽

10.1557/proc-305-211 ◽

1993 ◽

Vol 305 ◽

Author(s):

J. C. Arnold ◽

A. R. Eccott

Keyword(s):

Strain Rate ◽

Immersion Time ◽

Constant Strain Rate ◽

Tensile Tests ◽

Strain Rates ◽

Physical Ageing ◽

Diffusion Effects ◽

Craze Initiation ◽

Comparison Of Tests

AbstractThe effects of physical ageing and prior immersion time on the ESC behaviour of polycarbonate in ethanol were studied. Constant strain rate tensile tests were performed at a range of strain rates for samples with ageing times varying from 100 hours to 3000 hours and for prior immersion times of between 1 hour and 500 hours. Comparison of tests performed in ethanol and in air gave a good indication of the point of craze initiation. The results showed that there was a reduction in strain to crazing as the strain rate decreased, apart from with the lowest strain rate used. A longer prior immersion time also promoted craze formation. Both of these results are attributable to diffusion effects. Physical ageing had little effect on the ESC behaviour, due to the large amounts of deformation encountered in this system.

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A State Variable Modeling of Plasticity and Necking Under Uniaxial Tension

Journal of Engineering Materials and Technology ◽

10.1115/1.2904188 ◽

1992 ◽

Vol 114 (4) ◽

pp. 378-383 ◽

Cited By ~ 3

Author(s):

G. Ferron ◽

H. Karmaoui Idrissi ◽

A. Zeghloul

Keyword(s):

Strain Rate ◽

Uniaxial Tension ◽

Plastic Flow ◽

Constitutive Equations ◽

Growth Process ◽

Constant Strain Rate ◽

Uniaxial Tensile ◽

Long Wavelength ◽

State Variable ◽

Diffusion Controlled

Constitutive equations based on a state variable modeling of the thermo-viscoplastic behavior of metals are discussed, and incorporated in an exact, long-wavelength analysis of the neck-growth process in uniaxial tension. The general formalism is specialized to the case of f.c.c. metals in the range of intragranular, diffusion controlled plastic flow. The model is shown to provide a consistent account of aluminum behavior both under constant strain-rate and creep. Calculated uniaxial tensile ductilities and rupture lives in creep are also compared with experiments.

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A numerical and experimental investigation of AZ31 formability at elevated temperatures using a constant strain rate test

Materials & Design (1980-2015) ◽

10.1016/j.matdes.2009.09.009 ◽

2010 ◽

Vol 31 (3) ◽

pp. 1308-1316 ◽

Cited By ~ 28

Author(s):

G. Palumbo ◽

D. Sorgente ◽

L. Tricarico

Keyword(s):

Experimental Investigation ◽

Strain Rate ◽

Elevated Temperatures ◽

Constant Strain Rate ◽

Rate Test

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Some Implications of a Nonlinear Viscoelastic Constitutive Theory Regarding Interrelationships Between Creep and Strength Behavior of Ice at Failure

Journal of Offshore Mechanics and Arctic Engineering ◽

10.1115/1.3257088 ◽

1989 ◽

Vol 111 (2) ◽

pp. 144-148 ◽

Cited By ~ 5

Author(s):

B. D. Harper

Keyword(s):

Strain Rate ◽

Constant Strain Rate ◽

Nonlinear Viscoelastic ◽

Uniaxial Creep ◽

Strength Behavior ◽

Minimum Strain Rate ◽

Strength Constant ◽

Viscoelastic Constitutive Model ◽

Stress And Strain Rate ◽

Special Case

This study explores several possibilities for a correspondence in the behavior of ice at failure during uniaxial creep (constant stress) and strength (constant strain rate) experiments. The usual notion of failure in ice is employed (i.e., the occurrence of a minimum strain rate during a creep test and a peak or maximum stress during a strength test), and the behavior at failure is discussed in terms of a recently proposed nonlinear viscoelastic constitutive model for ice. It is demonstrated that no correspondence between creep and strength data can be expected in general; however, several approximate interrelationships do occur for the experimentally motivated special case of a constant (independent of stress and strain rate) failure strain.

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