Thermal expansion of Al-U and Al-U-Zr alloys

Abstract

The thermal expansion of Al-10.3U, Al-16.2U, Al-22U, Al-8.1U-1Zr, Al-16.2U-1Zr, Al-22U-2Zr, Al-30-U2Zr and Al-46U-3Zr alloys (all compositions are in wt%) were measured from room temperature to 550°C using a high temperature dilatometer. The coefficient of thermal expansion (CTE) was found to increase with temperature for Al-8.1U-1Zr and Al-10.3U alloys while for higher uranium containing ternary alloys namely Al-30U-2Zr and Al-46U-3Zr the CTE decreased with temperature. The CTE of Al-U and Al-U-Zr alloys generally decreased with increase in uranium content. The differences in the thermal expansion behaviour of these binary and ternary alloys have been attributed to their microstructures and the amount of UAl₃, UAl₄ and Al in these alloys.