Temperature dependence of thermodynamic properties of Si–Ti binary liquid alloys

This study is an attempt to extract useful thermodynamic information from experimental free energy of mixing of Si–Ti binary liquid alloy at different temperatures. A number of temperature dependent thermodynamic functions are calculated in the frame of a simple approach based on a statistical mechanical model. It is reported that the thermodynamic functions of Si–Ti alloy exhibit strong negative deviation from Raoult’s law across the whole concentration range and the impact of temperatures on the liquid alloy is explained. The energetics of mixing in the alloy has been explained through the study of activity, free energy of mixing, concentration fluctuations in the long-wavelength limits, chemical short-range order and diffusion. In addition, it is also observed that the tendency for intermetallic associations, which leads to the formation of SiTi compounds, decreases with the increase in temperature. This study reinforces further that useful thermodynamic information may be obtained from experimental data obtain using FactSage Thermo-Chemical Software and databases for binary liquid alloys.

► The paper deals with the segment of the Si–Ti alloys investigation, in the form of theoretical thermodynamic approach to their liquid properties.
► Ti-based alloys are widely used in different areas, have significant applications, especially in aerospace and biomedicine.
► The energetic of mixing in the alloys has been explained through the study of a number of thermodynamic functions.