Abstract:Kaolinite composites MK/Co-P and SK/Co-P were prepared by pretreatment and electroless deposition on two type of natural kaolinite produced from Maoming and Suzhou respectively. Their microstructures, magnetic properties and microwave absorption abilities were studied and compared. The results indicated that both kaolinite composites contained single phased Co-P coatings with hexagonal-closed-packed structure. In MK/Co-P, Co-P coatings were deposited on the surfaces of kaolinite flakes uniformly, where the contents of cobalt and phosphorus were determined to be 36.62 wt.% and 4.41 wt.%, respectively. By comparison, kaolinite microclusters were covered completely by Co-P coatings in SK/Co-P and the contents of Co and P were both decreased noticeably. In contrast to SK/Co-P, MK/Co-P shows enhanced saturation magnetization and coercivity together with much improved permittivity and permeability. It presents a maximum reflection loss of -27.32 dB and a effective absorbing bandwidth (reflection loss below -20 dB) covering 4.7 ~ 8.2 GHz at the thickness range of 2.0 ~ 3.0 mm, which would be suitable for applications in microwave devices.