Magnetism of Rapidly Quenched Sm1-xZrxCo5 Nanocrystalline Materials

Journal Article · Mon Jul 01 00:00:00 EDT 2013 · IEEE Transactions on Magnetics

DOI:https://doi.org/10.1109/TMAG.2013.2240440· OSTI ID:1211418

Zhang, WY; Valloppilly, S; Li, XZ; Liu, Y; Michalski, S; George, TA; Skomski, R; Shield, JE; Sellmyer, DJ

The effect of Zr addition on nanostructure and magnetic properties in nanocrystalline Sm1-xZrxCo5 (x = 0 - 0.6) has been investigated. (Sm, Zr)Co-5 with the CaCu5 structure was synthesized by melt spinning. The lattice parameters a and b decrease with x, whereas c increases. Thus, the unit cell volume of (Sm, Zr)Co-5 shrinks because the smaller Zr atoms occupy the sites of the larger Sm atoms. Zr addition decreases the grain size and induces the formation of planar defects. The coercivity decreases with x, due to weakening of magnetocrystalline anisotropy energy and effective intergrain exchange coupling. A very high coercivity of 39 kOe and energy product of 13.9 MGOe are obtained for x = 0. The remanence of (Sm, Zr)Co-5 increases with x. For x <= 0.4, the energy product slightly decreases with x. The results show that 40% of the Sm can be replaced by the less expensive Zr, with an energy-product reduction of only 10%. In addition, the planar defects are responsible for the change of coercivity mechanism from the nucleation-type of reverse domain for the x = 0 to the pinning-type of domain wall for the x = 0.4.

• Sponsoring Organization: USDOE Advanced Research Projects Agency - Energy (ARPA-E)
• OSTI ID: 1211418
• Journal Information: IEEE Transactions on Magnetics, Vol. 49, Issue 7; ISSN 0018-9464
• Country of Publication: United States
• Language: English