Bhatia-Thornton fluctuations, transport and ordering in partially ordered Al-Cu alloys

Abstract

The Bhatia-Thornton (BT) correlation functions namely the number-number, concentration-concentration and number-concentration correlation functions in liquid binary melts are important parameters for understanding the complexities in binary liquids. In this paper, the microscopic BT correlation functions of liquid Al-Cu alloys are investigated using square well (SW) potential under mean spherical model approximation. These correlation functions are linearly related to the Ashcroft-Langreth type partial structure factors. Thermodynamically important microscopic function i.e. concentration-concentration correlation function in the long-wavelength limit, S CC(0) is analytically calculated, which is well-known in BT formalism and is often used to characterized the mixing behavior in binary melts. The Warren-Cowley chemical short range order parameters, as function of Cu concentration is also computed in the liquid Al-Cu alloys through structural studies in the long wavelength limit, which gives valuable information regarding ordering in melts. The compound forming behavior in Al-Cu alloys is evidenced by the results obtained for the value of S CC(0) and . Further, transport properties in binary mixture have been determined by using BT-correlation functions and its long wavelength limit values. Kinetic as well as thermodynamic factors were taken care in the computation of dynamic properties of alloys. © 2019 IOP Publishing Ltd and SISSA Medialab srl.