Thermodynamic Characteristics, Phase Separation, and Nanomechanical Properties of Ternary Fe-Co-Cu Alloys with Equiatomic Fe and Co Compositions

摘要: The thermodynamic parameters for a series of Fe(100−x)/2Co(100−x)/2Cux (x from 10 to 90, at. pct) alloys including their characteristic temperatures, the enthalpy and entropy changes three phase transformations were determined systematically using differential scanning calorimetry (DSC). corresponding vertical section ternary Fe-Co-Cu diagram was predicted, relationships vs Cu content described by polynomial expressions. Metastable separation took place in those liquid with 30 ≤ x ≤ 70. temperatures outline metastable miscibility gap, critical undercoolings initiate measured as range 57 K 98 K. After such separation, (to γ(Fe, Co)) exhibited strongest undercooling ability x ≤ 70, whereas solid-state eutectoid transformation is comparatively higher x > 70. nanomechanical properties α(Fe, Co) (Cu) phases nanoindentation technique. In Fe20Co20Cu60 alloy, both had lowest nanohardness reduced elastic modulus, displayed severe creep behaviors, resulting mainly its conspicuous separation.