Stress-strain deformation vs. time

As a melt is subjected to a fixed stress or strain, the deformation versus time curve will show an initial rapid deformation followed by a continuous flow. Elasticity and strain are compared in Fig. 8-9 that provides (a) basic deformation vs. time curve, (b) stress-strain deformation vs. time with the creep effect, (c) stress-strain deformation vs. time with the stress-relaxation effect, (d) material exhibiting elasticity, and (e) material exhibiting... 

Fig. 1-6. (a) Basic deformation vs. time curve, (b) Stress-strain deformation vs. time (creep effect), (c) Strain-stress deformation vs. time (stress-relaxation effect). 

The gradual decrease in stress with time under a constant deformation (strain) and temperature. Stress relaxation is determined in creep test. Data is often presented as stress vs. time plot. The stress relaxation rate is given by the slope of the curve at any point. 

When the stress is suddenly applied in a creep test, only the dashpot offers an initial resistance to deformation, so the initial slope of the strain vs. time curve is... 

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