PHASE-EQUILIBRIA IN THE CU-FE-TI SYSTEM AT 1123-K

The isothermal cross-section through the ternary phase diagram Cu-Fe-T i at 1123 K was constructed by means of a special diffusion technique developed earlier. The results have been verified on essential points by the investigation of equilibrated alloys. Five ternary intermetalli c compounds designated as T-1, (Ti33Cu67-xFex; 1<x<2.5), T-2 (Ti40Cu60 -xFex; 5<x<17), T-3 (Ti43Cu57-xFex; 21<x<24), tau (Ti37Cu63-xFex; 6<x< 7) and tau(1) (Ti45Cu(55-x)Fe(x); 4<x<5) exist as equilibrium phases i n this system at 1123 K. Nearly 38 at.% Cu can be dissolved in cubic T iFe. This leads to an expansion of the lattice. It was found that at 1 123 K the Cu-based solid solution is in equilibrium with intermetallic compounds of the binary Ti-Fe system and with the ternary phases T-2 and T-3.