Preparation and Microwave Absorbing Properties of Ni-Al-Co Composite Hollow Microspheres

Abstract:

The SHS agglomerate power was made by grinding Al, Ni and Co powers with vesicant and adhesive. The Ni-Al-Co composite hollow microspheres were prepared by a self-propagating synthesis flame spraying quenching method. The microstructure and crystal structure of the hollow sphere power were studied by SEM, EDS and XRD. The results show that the spheres have hollow structure. At the high temperature of the oxyacetylene flame, the SHS reaction of the agglomerate is ignited. So the synthesized product becomes droplets. At the same time some gas is generated from vesicant so that the droplets become bubbles. The hollow droplets are injected into cold water and solidified to hollow microspheres. The permittivity and permeability were analyzed by a vector network analyzer. The microwave absorbing properties of the microspheres are good at band 6 GHz.