We discussed in lecture how in the early phase of a phase transformation, for example as a ß phase forms in a matrix of an a phase as shown in Fig 1.38(a), the interface between the two phases contributes to the Gibbs free energy of the ß phase. (a) In Figure 1.38(b), the Gibbs free energy curves of the ß phase are shown for a case (1) where the B phase is of radius r and (2) for the case where the ß phase has a radius of size. Write an expression for the difference in the Gibbs free energy of the two cases. (b) Notice the Gibbs free energy curve for the a phase on the left side of Figure 1.38(b). What can you say is different about the a phase in equilibrium with the ß phase when the ß phase is (1) of size r versus when the ß phase is (2) of size .

We discussed in lecture how in the early phase of a phase transformation, for example as a ß phase forms in a matrix of an a phase as shown in Fig 1.38(a), the interface between the two phases contributes to the Gibbs free energy of the ß phase. (a) In Figure 1.38(b), the Gibbs free energy curves of the ß phase are shown for a case (1) where the B phase is of radius r and (2) for the case where the ß phase has a radius of size. Write an expression for the difference in the Gibbs free energy of the two cases. (b) Notice the Gibbs free energy curve for the a phase on the left side of Figure 1.38(b). What can you say is different about the a phase in equilibrium with the ß phase when the ß phase is (1) of size r versus when the ß phase is (2) of size .

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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