INFLUENCE OF NI ADDITIONS ON THE LOW-TEMPERATURE MAGNETIC-PROPERTIES OF A CU-1-PERCENT MN ALLOY

dc susceptibility and magnetization measurements were made on three alloys with the nominal compositions Cu-1% Mn, Cu-15% Ni, and Cu-1% Mn-15% Ni. dc susceptibility [χdc=C/(T+θW)] measurements were made with a Curie-type balance from room temperature down to 77.2 K. Magnetization measurements consisted of M-H loops at 4.2 and 1.37 K, and initial magnetization runs from room temperature down to 1.37 K. The results were analyzed in terms of an addition of Ni to Cu-Mn. High-temperature χdc data were used to find θW, C, and μeff (from C and the concentration), and it is found that these properties are influenced only to a minor extent by the Ni addition. At low temperatures, however, a suppression of the freezing temperature and an enhancement in the superparamagnetic signal are noticed for Cu-Mn-Ni as compared to Cu-Mn. Finally, hysteretic loss and magnetization for the ternary at 4.2 K were compared to that of the Cu-Ni and Cu-Mn alloys in order to determine its suitability for use as matrix material in multifilamentary superconductive wire. © 1994 American Institute of Physics.