Analysis of antiphase domain growth in ternary FeCo alloys after different cooling rates and annealing treatments using neutron diffraction and positron annihilation

FeCo alloys are industrially important engineering materials which play an outstanding role in applications requiring soft magnetic materials. The challenge is to include ternary elements to improve the mechanical properties. Here noble elements as Pt or Pd were used for these experiments. With neutron diffraction and positron annihilation technique Fe67Co30Pt3 and Fe67Co30Pd3 (at. pct.) samples were measured to study the influence of different cooling rates on ordering and disordering. The ordering and disordering process is responsible for the mechanical properties in dependence of temperature. The correlation of ordering and defect density is described.

Research highlights▶ In-situ observation at high temperatures of atomic position change Fe and Co with neutron diffraction. ▶ Determination of antiphase domain growth with neutron diffraction. ▶ Determination of vacacny defects at antiphase domain boundaries with positron annihilation. ▶ Combination of neutron diffraction and positron annihilation to correlate ordering/disordering process and the defect density of ternary FeCo alloys.