Experimental Determination of Phase Equilibria in the Mn-Zn Binary System

Phase equilibria in the Mn-Zn binary system were experimentally determined by chemical composition examination, crystal structure determination, and thermal analysis. Major changes were detected for the β, ε, and δ phases. The β-B2 single-phase region could not be confirmed in the studied system because a disordered body-centered cubic structure, which is identical to the δMn phase, was confirmed in a quenched sample from the previously proposed region of β phase. The ε phase has been controversial whether the phase is separated into ε, ε₁, and ε₂ phases or not. By studying a diffusion couple and several alloy compositions, it was established that the ε, ε₁, and ε₂ phases are not separate and comprise a single ε phase. Furthermore, the δ phase is not present in the Zn-rich region of the system because the corresponding invariant reactions were not detected via thermal analysis.