PARTICLE INTERACTION IN BA-CU LIQUID MELTS

The heat of mixing (Delta H) of Ba-Cu alloys at 1080 K is studied calo rimetrically. The dependence of Delta H on the composition is nonmonot onic. Positive values of Delta H correspond to the region 0-65 at. % C u (the maximum Delta H = +3.4 kJ/mole is at -40 at, % Cu), and the neg ative values are in the region above 65 at. % Cu (the minimum Delta H = -0.8 kJ/mole corresponds to Cu13Ba), The results obtained are compar ed with literature data on Delta H(x) and with the form of the state d iagram. Possible reasons for the discrepancy with the experimental dat a are analyzed, The experimental trend to stratification in the Ba - C u system in the region of 65 at. % Cu is confirmed by Hildebrand-Mott calculation (Phi > 2RT).