Structural and magnetic behavior of Fe(Nb,Zr) rich alloys produced by mechanical alloying

Abstract

Fe80Nb7B12Cu1 and Fe80(NiZr)7B12Cu1, nanocrystalline alloys were synthesized in two high-energy ball milling devices (planetary, shaker). The microstructure, thermal and magnetic properties of the milled powders were characterized by X-ray diffraction (XRD), differential scanning calorimetry (DSC) and vibrating sample magnetometry (VSM); respectively. Milling device influences the microstructure and properties of final products. The results suggest more energetic milling in shaker mill. The main phase is always bcc Fe rich solid solution. Nevertheless, in Fe80Nb7B12Cu1 alloy minor Nb(B) phase is found after shaker milling and in Fe80(NiZr)7B12Cu1 alloy a low crystalline size Zr rich phase after planetary milling. Crystalline grain size ranges between 9.5 and 15.1 nm; lower values correspond to alloys with a second minor phase. Coercivity values ranges between 28.6 and 36.9 Oe.

Enhanced Room-Temperature Ionic Conductivity of NaCB11H12 via High-Energy Mechanical Milling

“…As mentioned above, the attempt to stabilize conductive phases of NCB at rt via planetary ball-milling led, after 86 h of milling time, only to the partial formation of fcc phase, in contrast to 30 min to start forming bcc phase via 3D milling (Figure S1). Hence, different milling conditions, such as more energetic mechanical milling provided by 3D mill, , can affect the polymorphism and eventually drive the stabilization of less common crystalline phases, as already shown for other systems, in both organic and inorganic structures. , …”

“…Hence, different milling conditions, such as more energetic mechanical milling provided by 3D mill, 48,66 can affect the polymorphism and eventually drive the stabilization of less common crystalline phases, as already shown for other systems, in both organic and inorganic structures. 67,68 Figure 2 reports the DC conductivity of MM-NCB as a function of inverse temperature. In contrast to the pristine sample, where the conductivity jumps at around 83 °C because of an order−disorder phase transition, for MM-NCB, this is no longer noticeable.…”