ESTIMATES OF THE FORMATION ENTHALPIES OF POINT-DEFECTS IN INTERMETALLIC COMPOUNDS WITH THE C15 STRUCTURE AND COMPARISON WITH EXPERIMENTS

Miedema's semi-empirical 'macroscopic' atom model, by which estimates of the enthalpy of formation of binary alloys can be calculated, is ex tended in order to be able to estimate values for the formation enthal py of anti-site and quadruple-defect disorder in C15 compounds. These values can be used to predict the type of disorder that is created in C15 compounds by heating or ballistic action. Ball milling experiments have been performed on some GdX2 C15 compounds. The results are repor ted and compared to the predictions obtained by the model. (C) 1998 Pu blished by Elsevier Science Limited. All rights reserved.