Magnetic properties and crystallization of Co_(68)Mn_(10)B_(10)Si_(12) and Co_(58)Mn_(20)B_(10)Si_(12) amorphous alloys

摘要

Co_(68)Mn_(10B_(10)Si_(12) and Co_(58)Mn_(20)B_(10)Si_(12) metallic glasses were prepared to investigate their magnetic properties and crystallization. It was shown that when the Mn content was above 10 at. percent, the amorphous alloy was paramagnetic whereas below 10 at. percent, the alloy remained ferromagnetic. The addition of Mn also substantially altered the crystallization path of the Co-rich amorphous alloy, producing intermetallic phases such as Co_2MnSi and CoSi_2 during devitrification. In addition, the higher Mn content in Co_(58)Mn_(20)B_(10)Si_(12) considerably delayed the onset of devitrification (approx 100 deg C) through more effective mixing Co and Mn atoms compared to Co_(68)Mn_(10)B_(10)Si_(12). However, the crystallization in Co_(58)Mn_(20)B_(10)Si_(12) proceeded much faster, once it was triggered. The Mn addition had far reaching effects on the magnetic properties of the Co-rich glass as well as on the crystallization behavior.