Magnetic properties of undercooled Co-based alloys

Abstract

Co-based melts in a glass flux can be undercooled nearly as strong as samples processed containerless by electromagnetic levitation. The undercooling technique is combined with the use of a Faraday-balance to measure magnetic susceptibility on highly undercooled melts. The magnetic susceptibility of Co and Co–Au is investigated as a function of temperature from stable liquid to undercooled liquid state using a Faraday-balance. When liquid Co-based alloys are undercooled the magnetisation steeply rises when temperature approaches the Curie temperature. The magnetisation is presented for Co and Co 90 Au 10 in solid and liquid state as a function of temperature. The results show that the magnetic susceptibility of the liquid undercooled samples follows a Curie–Weiss behaviour, from which Curie temperature and magnetic moment are inferred. In no case an undercooling below the Curie temperature was achieved.