A Thermodynamic Model for the Stacking- Fault Energy
نویسنده
چکیده
ÐA general thermodynamic model for calculating the energy of stacking faults is presented and applied to f.c.c. Fe±Cr±Ni alloys. A distinction is made between ideal stacking faults and real stacking faults which are associated with an ideal stacking-fault energy (SFE) and an eective SFE, respectively. The ideal SFE is characterized by a chemical energy volume term and an interphase surface energy term, whereas the eective SFE is de®ned by an additional strain energy volume term. The chemical and strain energy terms are evaluated from theoretical considerations. The interphase surface energy is calculated based on a comparison with experimental values obtained from Transmission Electron Microscopy (TEM) measurements. The results of this analysis show a good agreement between the calculated and experimental values. The model enables the determination of the ideal and eective stacking fault energies as a function of the Cr and Ni contents. The SFE dependence on the Cr vs Ni contents has the shape of a hyperbola. # 1998 Acta Metallurgica Inc. Published by Elsevier Science Ltd. All rights reserved.
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