Determination of α-aluminium solid solubility limits in the aluminium-uranium and aluminium-plutonium systems

Abstract

The α-aluminium solid solubility limits in the aluminium-uranium and aluminium-plutonium systems have been determined by metallographic methods. The maximum solid solubilities of uranium in aluminium and of plutonium in aluminium were found to be 0.06±0.02 wt % U and 0.05±0.02 wt % Pu respectively at the corresponding eutectic temperatures. The α Al-UAl₄ and α AI-PuAl₄ eutectic temperatures have been established by thermal analysis as 646° ±0.5°C and 650°±0.5°C respectively. At 350°C, the solid solubility decreased t° less than 0.04 wt % U in the Al-U system and to ess than 0.025 wt % Pu in the Al-Pu system. The αAl-UAl₄ eutectic temperature and the maximum solid solubility of plutonium in aluminium, as found in this investigation, do not agree with the values Ireported by previous workers.