Synchronistic preparation of fibre-like SiC and cubic-ZrO_2/SiC composite from zircon via carbothermal reduction process

摘要

Fibre-like SiC and cubic-ZrO_2/SiC composite were prepared respectively from zircon with yttrium oxide addition via carbothermal reduction process at 1600 ℃ for 4 h in an air atmosphere furnace, where the green samples were immerged in charred coal particles inside a high-temperature enclosed corundum crucible. The reaction products were characterized by XRD, XRF, XPS and SEM. The results indicate that ZrO_2 in the products was mainly existed in the form of cubic phase. The reacted samples mainly contain cubic ZrO_2, β-SiC and trace amounts of zircon, with the SiC accounting for 14.8 wt%. Furthermore, a large quantity of fibre-like SiC was surprisingly found to concentrate in the charred coal particles layers around the samples. This study obtains fibre-like SiC and cubic-ZrO_2/SiC composite synchronically from zircon via carbothermal reduction process, which also bring a value-added high-performance application for natural zircon.