Abstract
A tentative phase diagram is given for the aluminium-rich end of the Re—Al system; it is based on both the present and previous investigations. A new phase ReAl4 is reported; a relationship between its triclinic structure and the monoclinic structure of MoAl4 is suggested. The probable similarity between the aluminium-rich sides of the phase diagrams of the Re—Al and Tc—Al systems is also indicated.