Preparation and mechanism analysis of a new type hollow multiphase ceramic micro-spheres

Self-reactive quenching technology and Al + Cr2O3 + Si + Sucrose + Epoxy Resin as reaction system are used to prepare hollow multiphase ceramic micro-spheres. Forming mechanism of the quenching products is analyzed through high-speed photography, water quenching method, SEM, XRD and EDS. The results show that agglomerate powders go through three phases during the flight process in flame field: heated ignition, ceramic droplets formed and cooled rapidly. The quenching products consist of two parts: one is the hollow irregular porous particles; the other is the hollow ceramic micro-spheres with smooth surface. The high heat released from aluminothermic reaction guarantees the forming of hollow multiphase ceramic micro-spheres and SiC. The porous, open and hollow structure is essentially caused by the large volume of gas formed during the reaction process.