Free volume (FV) model

 

Procedure

Dynamic measuring regime.

One measurement at a given heat-treatment (w-,Ta,ta) and heating rate, w+.

Then the activation energy ΔE*FV(w-Ta,ta) (kinetic parameter) could be determined:

ΔE*FV = ΔE*DNLR                                        (ΔE*DNLR  - material parameter)

 

 

Model assumes:

Second order kinetics.

Only one relaxation process.

A three-parameter non-linear relaxation time τ(T,t,Ta,ta) = AFVexp[ΔE*FV/(RT)exp1/[α(T,t,Ta,ta) – αFV(Ta,ta)].

Model parameters (ΔE*FV, AFV, αFV) colud be determined by numerical non-linear curve fitting.

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