15 lines
696 B
Markdown
15 lines
696 B
Markdown
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Viscous materials, like water, resist both shear flow and strain linearly with
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time when a stress is applied. Elastic materials strain when stretched and
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immediately return to their original state once the stress is removed.
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A viscoelastic material has the following properties:
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[Hysteresis](Hysteresis.md) is seen in the stress–strain curve
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stress relaxation occurs: step constant strain causes decreasing stress
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creep occurs: step constant stress causes increasing strain
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its stiffness depends on the strain rate
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A viscoelastic substance dissipates energy when a load is applied, then removed.
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### nota bene
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The properties of a viscoelastic layer change with the frequency of excitation
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