Nanocrystalline PrCo 5 alloy obtained by mechanical milling

Abstract

Nanostructured PrCo 5 powders were obtained by mechanical milling, annealing in high vacuum in sealed ampoules and subsequent quenching in water. The highest intrinsic coercivity value ( i H C = 1.385 MA/m) and magnetization ratio ( σ r/ σ max = 0.66) were determined in powders milled for 240 min and annealed at 1073 K for 1 min. The enhanced remanence ( σ r/ σ max > 0.5) suggests strong exchange interactions between the adjacent crystallites. This is in good agreement with the small average crystallite size, 〈 D〉 = 15 nm. The high magnetic properties observed in these nanostructured PrCo 5 intermetallic alloys have their origin in its relatively high uniaxial magnetocrystalline anisotropy field, and in the homogeneous nanostructure developed by mechanical milling process and subsequent annealing.