Study on thermodynamic and elastic properties of B2-FeSi by statistical moment method

The thermodynamic and elastic theory of B2 substitutional alloy AB and B2 interstitial alloy AB under temperature and pressure are derived by the statistical moment method. In the case of zero concentration of substitutional atoms B and interstitial atoms B, we obtain the thermodynamic and elastic theory of main metal A with simple cubic structure. Our numerical calculations according to the model of interstitial alloy for B2-Fe99Si1 and the model of substitutional alloy for B2-Fe50Si50 in the temperature interval from zero to 1500 K and the pressure interval from zero to 160 GPa are in relatively good with experiments and other calculations.