Thermal Stability of Nanocrystalline Soft Magnetic Alloys with Different Inhibitors

In this work, the effect of different inhibitors on the thermal stability of the magnetic properties in Fe73.5Cu1M3Si13.5B9 nanocrystalline alloys, where M = Nb, W, Mo, was investigated. Nanocrystalline alloy with tungsten has the greatest thermal stability. The change in the magnetic properties in the ageing process was associated with vacancies and vacancy clusters, the formation of which is facilitated by large atoms of inhibitory elements occupying free positions in the substitution solid solution.

The phase diagram of K0.5Na0.5NbO3–Bi1/2Na1/2TiO3

The phase diagram of the lead-free piezoelectric (1 − x)K0.5Na0.5NbO3–xBi1/2Na1/2TiO3 system has been studied by high-resolution synchrotron powder diffraction, neutron powder diffraction and selected area electron diffraction. The two lead-free piezoelectric materials K0.5Na0.5NbO3 and Bi1/2Na1/2TiO3 form an infinite substitution solid solution. The orthorhombic (O), monoclinic (M), tetragonal (T) and rhombohedral (R) phases and the phase coexistence of M (Pm) + T (P4mm) for 0.02 < x ≤ 0.14, T (P4bm) + pseudocubic (Pm{\overline 3}m) for 0.14 < x ≤ 0.87 and T (P4bm) + R (R3c) for 0.87 < x ≤ 0.96 have been investigated at room temperature, with a subtle change in the structure observed. The oxygen octahedral tilt system has been mapped as a function of composition and temperature. The results indicate that K0.5Na0.5NbO3–Bi1/2Na1/2TiO3 does not display a morphotropic phase boundary like lead zirconate titanate, and that the most significant structural changes as a function of composition occur near x = 0.14 and x = 0.87 as a result of ionic disorder at the A and B sites in the perovskite ABO3 structure at room temperature.