L3: Mechanical Behaviour 2 Flashcards Preview

Ma ME523: Polymer And Polymer Composites > L3: Mechanical Behaviour 2 > Flashcards

Flashcards in L3: Mechanical Behaviour 2 Deck (7)
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What is the advantage and disadvantage of the KV and Maxwell models?

KV: acceptable approximation for creep/recovery behaviour. Does not account for stress relaxation
Maxwell: Can account for stress relaxation. Poor description of creep and recovery


What is the arrangement of the Standard Linear Model?

1 large spring in parallel with a spring and dashpot which are in series


What is the initial extension and relaxation behaviour controlled by in the SLM?

Initial: the dashpot
Relaxation: the interplay of both spring and dashpot elements


What is the asymptotic value for strain in the KV model?



What constants must be chosen to show the KV and Maxwell models are special cases of the SLM?

Maxwell: E2 (big spring) = 0
KV: E1 (small spring) = infinite (divide through by E1)


Which factors form a 3D relationship for viscoelastic polymers?



How is D(t) (creep compliance) determined?

Usually will be told to use Maxwell or KV model - D(t) = strain(t)/stress
See slides for equation for each