Numerical analysis of phase decomposition in A-B binary alloys using Cahn-Hilliard equations

• Autor(a) principal: Lezama-Alvarez,Susana
• Data de Publicação: 2013
• Outros Autores: Avila-Davila,Erika O., Lopez-Hirata,Victor M., Gonzalez-Velazquez,Jorge L.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Materials research (São Carlos. Online)
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392013000500003
• topic: A-B binary alloys; phase decomposition; linear and nonlinear Cahn-Hilliard equations; microstructural simulation

The analysis of phase decomposition was carried out using the nonlinear and linear Cahn-Hilliard equations in a hypothetical A-B alloy system with a miscibility gap. These equations were solved by the explicit finite difference method assuming a regular solution model. The supersaturated solid solution and decomposed phases were considered to have an fcc structure. Different aging temperatures and thermodynamic interaction parameters ΩA-B were used to simulate different alloy systems. The numerical simulation results showed that the growth kinetics of phase decomposition in the alloy with 30at.% A was slower than that of 50 at.% A. Additionally, the start time and modulation wavelength of phase decomposition are strongly affected by the thermodynamic interaction parameter ΩA-B value. The numerical simulation results showed that the growth kinetics of phase decomposition with the linear equation is slower than that with the nonlinear one.