Acta Phys. -Chim. Sin. ›› 2012, Vol. 28 ›› Issue (07): 1586-1592.doi: 10.3866/PKU.WHXB201205042

• THERMODYNAMICS, KINETICS, AND STRUCTURAL CHEMISTRY • Previous Articles     Next Articles

A New Model for the Configurational Entropy of Mixing in Liquid Alloys Based on Short-Range Order

QIN Jing-Yu   

  1. Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials Ministry of Education, Shandong University, Jinan 250061, P. R. China
  • Received:2012-03-31 Revised:2012-05-04 Published:2012-06-07
  • Contact: QIN Jing-Yu E-mail:qinjy@sdu.edu.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (50971082).

Abstract:

A new model has been developed to calculate the configurational entropy of mixing in liquid alloys involving consideration of chemical and topological short-range order. The entropy of mixing for an equiatomic random mixture was naturally reached by this model. The application of this model to both hypothetic and real binary liquid alloys demonstrated that the chemical short-range order always decreased the configurational entropy of mixing, whereas complicated behavior was found with the atomic size effect. The configurational entropy of mixing increased when the larger atoms entered into the matrix of the smaller atoms, whereas it decreased when the smaller atoms were mixed into the matrix of the larger atoms. The maximum of the configurational entropy of mixing was not located at the eutectic composition in these alloys.

Key words: Liquid alloy, Short-range order, Configurational entropy of mixing

MSC2000: 

  • O642