Theoretical investigation of structural, electronic, mechanical and thermodynamic properties of W-Ru alloys: Promising high temperature alloy materials

•Although the bulk modulus of W13Ru3 alloy decreases with increasing temperature, it is higher than that of W, exhibiting high temperature strength characteristics.•The thermal expansion coefficient of W13Ru3 alloy decreases with increasing temperature, and is lower than that of W, indicating that doping of Ru (18.75 at.%) can inhibit the thermal expansion behavior.•The thermal conductivity of W13Ru3 exceeds that of W14Ru2 at 360 K, W15Ru1 at 750 K and W at 1120 K, and then maintains a thermal conductivity of 11.50Wm-1K-1, indicating that doping of Ru (18.75 at.%) can improve the thermal conductivity.•At 0 K, although the mechanical strength of W-Ru alloys is lower than that of W, its ductility is better than that of W. The structure models of W15Ru1, W14Ru2, W13Ru3 and W12Ru4 alloys were constructed in this study. Based on phonon spectrum, the W12Ru4 alloy has thermodynamic instability. By first principles, the mechanical and thermodynamic properties of W16, W15Ru1, W14Ru2 and W13Ru3 alloys have therefore been studied. The research shows that the bulk modulus of W15Ru1 and W14Ru2 alloys decreased with temperature increased, which is smaller compare with pure W. However, although the bulk modulus of W13Ru3 alloy also decreased with temperature increased, it is obviously higher compare with pure W, and shows high temperature strength properties. For W15Ru1 and W14Ru2 alloys, the coefficient of thermal expansion increased with temperature increased, and are significantly greater compare with pure W. For W13Ru3 alloy, the coefficient of thermal expansion decreased with temperature increased, and is obviously smaller compare with pure W, indicating that the thermal expansion is inhibited by doping of Ru (18.75 at.%). The thermal conductivity of W15Ru1 and W14Ru2 alloys is lower compare with pure W. The thermal conductivity of W13Ru3 exceeds that of W14Ru2 alloy at 360 K, W15Ru1 alloy at 750 K and W at 1120 K, and then maintains a thermal conductivity of about 11.50Wm-1K-1, indicating that doping of Ru (18.75 at.%) can increase the thermal conductivity.