This preview shows page 1. Sign up to view the full content.
Unformatted text preview: DATA: enthalpy of transformation, H = 0.6 RT e molar volume of , V = 15 cm 3 mol1 lattice parameter in , a o = 3.2 x 108 cm surface energy along  , = 40 erg cm2 lattice diffusivities at 900 K, D L = 1010 cm 2 s1 diffusivity across  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....
View
Full
Document
 Spring '02
 CHEN

Click to edit the document details