Synthesis of Ultra-Fine Zirconium Diboride Powders by Polymer Template Method Following by Microwave Sintering

Zirconium diboride (ZrB2) nanoparticles were synthesized by polymer template method using zirconyl (ZrOCl2∙8H2O), boric acid (H3BO3), Chitosan and Mannitol (C6H14O6) with microwave sintering method. SEM and other analytic methods were used to study the phase composition and the microstructure of the nanoparticles.The influence of the ratio of zirconium to boron and carbon on the purity of ZrB2 powders, as well as the synthesis temperature and the holding time were studied. Pure ZrB2 at the molar ratio of C/Zr/B=10/5.2/1 can be obtained. The optimum parameter for microwave sintering is 1320 °C for 1h, which is about 300°C lower than conventional carbonization reduction to obtain ZrB2 powders. The synthesized powders have small particle sizes (50nm) with nearly spherical morphology.