Synthesis and pyrolysis of single-source precursor for HfCxN1-x-SiC ceramic with different SiC contents

A novel single-source precursor was synthesized to prepare HfCxN1-x/SiC multiphase ceramics by using hafnium chloride (HfCl4), diallylamine (DAA) and polycarbosilane (PCS). We conducted an investigation of the synthesis process, polymer-to-ceramic conversion, as well as the microstructure and phase evolution of HfCxN1-x/SiC multiphase ceramics with different levels of SiC content. The results showed that the core-shell particles of HfCxN1-x-carbon were embedded homogeneously in the beta-SiC matrix which is beneficial for preventing grain growth and improving oxidation resistance. Based on data from oxidation tests, the ceramics improved the oxidation temperature and remained stable at a high temperature (1500 degrees C) with oxidation layer formation on the surface. Due to the highly cross-linked structure without oxygen, high ceramic yield, homogeneous composition and excellent oxidation resistance of the pyrolysis product, the as-prepared precursor is a promising material for making high-performance composite ceramics.

Automated summary

A novel single-source precursor was synthesized to prepare HfCxN1-x/SiC multiphase ceramics. The results showed that the ceramics had a homogeneous microstructure and phase evolution, which effectively prevented grain growth and improved oxidation resistance. Due to the absence of oxygen, high ceramic yield, homogeneous composition, and excellent oxidation resistance, the prepared precursor is a promising material for making high-performance composite ceramics.