Unformatted text preview: DATA: enthalpy of transformation, ∆ H = 0.6 RT e molar volume of α , V α = 15 cm 3 mol1 lattice parameter in α , a o = 3.2 x 108 cm surface energy along αβ , γ αβ = 40 erg cm2 lattice diffusivities at 900 K, D L = 1010 cm 2 s1 diffusivity across αβ interface at 900 K, D I = 109 cm 2 s1 2. Assuming interfacereaction controlled growth, it can be shown that the volume fraction transformed in a firstorder phase transformation, X, as a function of time, t, at a constant temperature is given by X = 1 − exp − kt n ( ) where k is a constant which is a function of nucleation and growth rates. Show that n is between 1 and 2 in a fiber....
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 Spring '02
 CHEN
 Thermodynamics, α, 8 cm, 108 cm, allotropic phase transformation, 40 erg

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