Processing and characterization of pure cordierite and zirconia-doped cordierite ceramic composite by precipitation technique

Abstract

Pure cordierite and cordierite-ZrO2 composite (5-20 wt%) ceramics for various stoichiometric compositions were synthesized from standard raw materials by a novel precipitation technique. The analytical techniques such as X-ray diffraction, simultaneous thermogravimetric and differential thermal analysis, Fourier transform infrared spectroscopy, scanning electron microscopy and bulk density were employed to evaluate the properties and microstructure. Results show that the ceramic composites consist of cordierite and zircon phases. The cordierite-zirconia (20 wt%) increased the fracture toughness value from 3.38 to 3.94 MPa, which is mainly due to martensitic transformation present in zirconia. The flexural strength of composite was found to increase from 126.46 to 297.62 MPa. The thermal expansion coefficients of cordierite and cordierite-zirconia (20 wt%) were 4.08×10-6 and 4.42×10-6 °C-1 which may be due to the addition of zirconia.