Thermal conductivity and thermal expansion were measured for the L1 2 intermetallic compounds Rh 3X (X = Ti, Zr, Hf, V, Nb, Ta) in the temperature range 300-1100 K to evaluate the feasibility of applying the compounds as ultra-high temperature structural materials. The thermal conductivities of Rh 3X are widely distributed over the range 32-103 W m -1 K -1 at 300 K, but the differences between the thermal conductivities diminish at higher temperatures. A trend is observed in that the thermal conductivity of Rh 3X is greater if the constituent X belongs to Group 5 rather than to Group 4 in the Periodic Table. The coefficient of thermal expansion (CTE) values of Rh 3X increase slightly with increasing temperature; values are concentrated around 10 × 10 -6 K -1 at 800 K. CTE values of Rh 3X decrease as X appears lower in the Periodic Table. It is demonstrated that Rh 3Nb and Rh 3Ta are suitable for ultra-high temperature structural applications due to their higher thermal conductivities and smaller CTE values.
ASJC Scopus subject areas
- Metals and Alloys