The isothermal sections of the Cu-Ni-Fe ternary system at 600, 800, 1000 and 1050 degrees C

The isothermal sections of the Cu-Ni-Fe ternary system at 600, 800, 1000 an d 1050 degrees C were determined using ternary diffusion couples and electr on probe microanalysis. The single-phase region alpha(Fe) at the Fe-rich co rner and the three-phase regions (gamma(1) + gamma(2) + alpha(Fe)) at 600 a nd 800 degrees C were determined, and the relationships of equilibrium phas es alpha(Fe)/gamma(1), alpha(Fe)/gamma(2) and gamma(1)/gamma(2) were obtain ed. The miscibility gaps in the Cu-Ni-Fe system at above four temperatures were also reconfirmed. In the miscibility gaps, the directions of tie-lines are all directed toward the Cu-rich corner.