Aufbau und magnetische Eigenschaften manganreicher Cu-Mn- und Mn-Sn-Legierungen

The phase equilibria on the Mn-rich side of the systems Cu-Mn and Mn-Sn were determined by susceptibility measurements at high temperatures. The phase relationships observed on the Mn-rich side of the system Cu-Mn as well as the susceptibility transformation diagram are in good accordance with the phase diagrams given in the literature. According to our measurements in the system Mn-Sn the -Mn phase field extends to about 10.2 at.% Sn at 1 302 K. The -Mn phase ranging to 7.5 at.% Sn was found to decompose eutectoidally at 1 315 K. The peritectic formation of the hexagonal phase with the approximate composition of Mn₃Sn occurs at 1 257 K. The Mn-rich boundary of the two-phase field -Mn+Mn₃Sn is located at about 10 at.% Sn.The magnetic susceptibility of liquid Mn-rich Cu-Mn and Mn-Sn alloys follows a modified Curie-law. Above a critical concentration—14 at.% Cu in the system Cu-Mn and 11.2 at.% Sn in the system Mn-Sn—localized magnetic moments due to the Mn atoms are observed.

Herrn Prof. Dr.Kurt L. Komarek anläßlich seines 60. Geburtstages gewidmet.