Excellent high temperature elasticity and thermodynamic properties of W-Cr alloys: A first-principles study

Abstract

The mechanical and thermodynamic properties of W-Cr alloys (including W15Cr1, W14Cr2, W12Cr4 and W8Cr8 alloys) are investigated by the first-principles study. Meanwhile, the investigation of pure W is also carried out to verify the reliability of the calculation in this paper. The results show that W-Cr alloys are thermodynamically stable and possess the characteristics of advanced materials. The bulk modulus of W-Cr alloys shows the essence of high elasticity at high temperature, which may be a major discovery. The W-Cr alloys belong to medium expansion materials and the thermal expansion coefficients of W12Cr4 and W8Cr8 alloys are significantly lower than that of pure W and other alloys, indicating that the addition of Cr can inhibit the thermal expansion behavior of pure W at high temperature. The thermal conductivity of W-Cr alloys is more obviously higher than that of pure W at high temperature, indicating that doping of Cr can improve the thermal conductivity of pure W. At 0 K, the ductility of W15Cr1 and W14Cr2 alloys is lower than that of pure W, while the ductility of W12Cr4 and W8Cr8 alloys is better than that of pure W, which indicates that the ductility of pure W can be improved by adding higher concentration of Cr. By investigating the mechanical and thermodynamic properties of W-Cr alloys, the theoretical reference is provided for its application in the field of nuclear fusion.

Keywords

• First wall W-Cr alloy
• First-principles
• High temperature elasticity
• Thermodynamic properties