Thermal conductivity of Ni3V–Ni3Al pseudo-binary alloys

•The thermal conductivity λ of Ni3V–Ni3Al pseudo-binary alloys was investigated.•In single phase alloys, λ decreases by increasing deviation from stoichiometry.•In Ni3V–Ni3Al two-phase alloys, λ decreases with increasing Al content.•λ increases with temperature for all alloys except for stoichiometric Ni3V.•The compositional dependence of λ is similar between 293 K and 1073 K.

The effect of changes in the composition and microstructure of the Ni3V–Ni3Al pseudo-binary alloys on their thermal conductivity has been investigated. For Ni3V and Ni3Al-based single-phase alloys, the thermal conductivity shows a maximum value at the stoichiometric compositions, and it decreases as the V (or Al) content of the Ni3Al (or Ni3V) alloy increases, following the Nordheim rule. For Ni3V–Ni3Al two-phase alloys, the thermal conductivity of the constituent Ni3Al phase exhibits a smaller value than that of the Ni3V phase. Eventually, the thermal conductivity of the two-phase alloys decreases as the Al content increases because of the increase in the volume fraction of the Ni3Al phase with low conductivity. As the temperature increases from 293 K to 1073 K, the conductivity increases for all of the alloys but not for stoichiometric Ni3V. However, the dependence of the thermal conductivity on the alloy composition between 293 K and 1073 K is similar. Hence, it is confirmed that the thermal conductivity of the Ni3V–Ni3Al pseudo-binary alloys is controlled by the composition and volume fraction of the constituent phase.