Preparation of hollow ceramic microspheres absorbent based on self-reactive quenching technology

摘要

Al+Ba O2 +Fe2O3 +sucrose and O2 as reaction system and feeding gas, respectively, are used to prepare hollow multiphase ceramic microspheres(HMCMs) absorbent based on self-reactive quenching technology. The morphologies, particle size distribution,hollow structure and phase compositions were characterized by scanning electron microscope(SEM), X-ray diffraction(XRD) and size analysis. The results show that the quenching products possess high sphere-forming rate, and most of them are hollow structures. Owing to the self-burst,the particle size is between 40 and 70 lm. The phase compositions contain Al2O3, Fe3O4, Fe2O3, Ba2Fe14O22,Ba O2 and Ba Fe4O7. The microwave absorbing tests show that the lowest reflectivity of HMCMs is-19 d B. The frequency bands less than-10 d B are from 13.0 to15.8 GHz. The reasons for HMCMs possessing good microwave absorbing properties may be their magnetic and electrical properties as well as special hollow structure.