Synthesis of ZrC-ZrB₂ composite powders by pirac method

ZrC-ZrB₂ composite ceramic powders are synthesized by a powder immersion method using Zr and B4C powders as reactants. Phase composition and microstructure of the treated powders are characterized by employing X-ray diffraction and scanning electron microscopy. Results show that contents proportion of the produced ZrC and ZrB2 varies with proceeding temperatures and the initial powders composition. Thermodynamics analysis and experimental results indicate that the mole ratio of Zr to B₄C should be appreciably small than 3:1 and treated at 900 °C for 2h is more suitable to make the Zr and B4C completely reacted and without Z1O2 remained.