Phase equilibrium S.J.T.U. Phase Transformation and Applications When a material composed of a single component exists in different physical states, the two states will be at equilibrium when the molar Gibbs free energies of the two states are equal. SJTU Thermodynamics of Materials Fall 2018 ©X.J.Jin Lecture 7 equilibrium IPhase Transformation and Applications S. J. T. U. SJTU Thermodynamics of Materials Fall 2018 © X. J. Jin Lecture 7 equilibrium I Phase equilibrium When a material composed of a single component exists in different physical states, the two states will be at equilibrium when the molar Gibbs free energies of the two states are equal