J Mater Sci Technol ›› 2008, Vol. 24 ›› Issue (05): 712-714.

• Research Articles • Previous Articles     Next Articles

Effect of Bath pH on the Squareness of Electroless CoNiWP Magnetic Films

Haibin CHENG, Shuai XU, Wenyu ZHAO, Suling ZHAO, Pengcheng ZHAI, Zhigang SUN, Qingjie ZHANG   

  1. State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China
  • Received:2007-04-17 Revised:2007-10-20 Online:2008-09-28 Published:2009-10-10
  • Contact: Qingjie ZHANG

Abstract: Electroless CoNiWP magnetic films were prepared by varying the bath pH and then characterized by energy dispersive X-ray analysis, X-ray diffraction and magnetic force microscopy. It has been found that the microstructure and the magnetic properties of films were influenced greatly by the bath pH. At the bath pH 8.06, the grain size and coercivity of the films reach maximum, while the squareness (Mr=Ms) of MH curves reaches minimum. The Henkel plots indicates that the exchange-coupling interaction is very weak at this pH, which may be caused by phase-separation and large grain size, and then results in the lowest squareness. At pH above 8.5, obvious exchange-coupling interaction is observed because of the inexistence of phase-separation and the refinement of grain size.

Key words: CoNiWP magnetic film, Bath pH, Squareness, Exchange-coupling interaction