On the α–α′ miscibility gap of Fe–Cr alloys

Experimental data on partial ordering and α′ precipitation in Fe–Cr alloys and ferritic steels containing up to 15 at.% Cr are summarized. From this data and computer simulations employing the most advanced Fe–Cr cohesive models, the Fe-rich phase boundary of the α–α′ miscibility gap is constructed. This boundary is critically compared with the standard (CALPHAD) Fe–Cr phase diagram in the same concentration range and a significant modification of the latter is proposed.