Phase field simulation of particle growth and Ostwald ripening for Cu-Pb hypermonotectic alloy

Cahn-Hilliard equation coupling with thermodynamic data was solved by Fourier transformation spectrum method with high efficiency and accuracy, and the particle growth and Ostwald ripening for Cu-Pb hypermonotectic alloy at the isothermal condition were simulated. The simulation results show that the particle growth and Ostwald ripening in two liquid phase fields of the alloy can be realized by the adjusting the gradient coefficient and mobility ratio. The growth of singular nucleated particles in a supersaturated matrix depends on the adjustment of free energy function, and the smaller the gradient coefficient, the more distinct the steepness of concentration profile is. Growth rate of particle radius is in good agreement with the Zener's law. Size distribution of reduced particle radius was computed and its peak value changed from smaller to large than the average radius.