THERMAL-EXPANSION OF AL-U AND AL-U-ZR ALLOYS

The thermal expansion of Al-10.3U, Al-16.2U, Al-22U, Al-8.1U-1Zr, Al-1 6.2U-1Zr, Al-22U-2Zr, Al-30U-2Zr and Al-46U-3Zr alloys (all compositio ns are in wt%) were measured from room temperature to 550 degrees C us ing a high temperature dilatometer. The coefficient of thermal expansi on (CTE) was found to increase with temperature for Al-8.1U-1Zr and Al -10.3U alloys while for higher uranium containing ternary alloys namel y Al-30U-2Zr and Al-46U-3Zr the CTE decreased with temperature. The CT E of Al-U and Al-U-Zr alloys generally decreased with increase in uran ium content. The differences in the thermal expansion behaviour of the se binary and ternary alloys have been attributed to their microstruct ures and the amount of UAl3, UAl4 and Al in these alloys.