CALORIMETRIC RESEARCH ON THE HEAT OF FORMATION OF LIQUID ALLOYS OF COPPER WITH GROUP IIIA AND GROUP IVA METALS

Using a high-temperature isoperibolic calorimeter of our own design we have determined the concentration dependences of the enthalpy of mixi ng for alloys of copper with scandium, yttrium, lanthanum, titanium, z irconium, and hafnium. The directly measured enthalpies of dissolution of solid group IVA metals in liquid copper are converted into partial molar enthalpies of mixing, taking into account the data on the high temperature component of the enthalpies and the enthalpies of fusion o f the pure components. The enthalpies of mixing of the liquid alloys a re given in tables and equations. The thermodynamic properties are int erpreted within the framework of the theory of an ideal associative so lution.