Stress-Relaxation and Creep Behavior

Stress relaxation and creep behavior for plastics are closely related to each other so that one can be predicted from knowledge of the other. Therefore, such deformations in plastics can be predicted by the use of standard engineering elastic stress analysis formulas where the elastic constants E and y can be replaced by their viscoelastic equivalents given in equations (2-2) and (2-3). 

Xia H, Song M, Zhang Z and Richardson M (2006) Microphase separation, stress relaxation, and creep behavior of polyurethane nauocomposites, J Appl Polym Sci 103 2992-3002. 

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