Author(s)

M. Lamichanne, B. K. Rai, S. R. Mishra, V. V. Nguyen, J. P. Liu

Department of Physics, The University of Memphis, USA.
Department of Physics, The University of Texas, Arlington, USA.

Composites of SmCo₅-FeNi and SmCo₅-FeCo, hard-soft magnetic materials, have been synthesized via electroless plating of magnetically hard SmCo₅ powder particles with magnetically soft FeNi and FeCo, respectively. The influence of coating thickness of soft magnetic layers on the structure and magnetic properties of the composite has been studied. Overall FeNi coating was found to be less dense compared to FeCo for the same plating duration. Structurally the coat ing was found to be nodular in morphology. These coating have dramatic effect on the overall magnetic property of the composite. As compared to FeNi coated SmCo₅ composite, two-fold increase in the saturation magnetization has been observed upon coating SmCo₅ (M_s~28 emu/g) with FeCo to a value 56 emu/g. The coercivity of composite powder was found to decrease with increasing the coating layer thickness. The absence of exchange spring behavior in the hard-soft composite is attributed to magnetically soft layer thickness exceeding the theoretical length limit for exchange-spring coupling.

Electroless Plating; Hard-Soft Composites; Exchange Spring

M. Lamichanne, B. Rai, S. Mishra, V. Nguyen and J. Liu, "Magnetic Properties Hard-Soft SmCo₅-FeNi and SmCo₅-FeCo Composites Prepared by Electroless Coating Technique," Open Journal of Composite Materials, Vol. 2 No. 4, 2012, pp. 119-124. doi: 10.4236/ojcm.2012.24014.