Rod Milling에 의해 제작된 비평형 Al(Fe-Cu) 합금 분말의 형성 및 Chemical Leaching

Abstract

We report the structure, thermal and magnetic properties of a non-equilibrium Al0.6(Fe50Cu50)0.4 alloy powder produced by rod milling and chemical leaching. An X-ray diffractometry(XRD), a transmission electron microscope(TEM), a differential scanning calorimeter(DSC), a vibrating sample magnetometer(VSM), and superconducting quantum interference device(SQUID) were utilized to characterize the as-milled and leaching specimens. The crystallite size reached a value of about 8.82 nm. In the DSC experiment, the peak temperatures and crystallization temperatures decreased with increasing milling time. The activation energy of crystallization is 200.5 kJ/mole for as-milled alloy powder. The intensities of the XRD peaks of as-milled powders associated with the bcc type Al0.5Fe0.5 structure formative at 350℃ sharply increase with increasing annealing temperature. Above 400℃, peaks alloted to Al0.5Fe0.5 and Al5Fe2 are observed. After annealing at 600℃ for 1 h, the leached L1 specimen transformed into bcc α-Fe and fcc Cu phases, accompanied by a change in the structural and magnetic properties. The saturation magnetization decreased with increasing milling time, and a value of about 8.42 emu/g was reached at 500 h of milling. The coercivity reached a maximum value of about 142.7 Oe after 500 h of milling. The magnetization of leached specimens as function of fields were higher at 5 K, and increased more sharply at 5 K than at 100 K.