Effects of sintering temperature on pore characterization and strength of porous cordierite–mullite ceramics by a pore-forming in-situ technique

Abstract

AbstractPorous cordierite–mullite ceramics with high strength were prepared by a pore-forming in-situ technique. The phase compositions, pore characteristics, and strength were investigated through X-ray diffractometry, scanning electron microscopy, and a microscopy measurement method. It is found that the sintering temperature strongly affects the formation of cordierite and mullite and the sintering, and thus changes the pore characteristics and strength. The formation of cordierite and mullite takes place on a large scale at 1430°C. The pore size distributions are bimodal in specimens sintered at 1370°C, 1400°C, and 1430°C, and mono-modal in a specimen sintered at 1450°C. The strength increases slightly when the sintering temperature increases from 1370°C to 1400°C, and increases significantly when the sintering temperature is increased to 1430°C. The most appropriate mode is a specimen sintered at 1430°C which has high cordierite (42 wt.%) and mullite content (53 wt.%), high apparent porosity (44%), high compressive strength (30.6 MPa) and a relatively homogeneous pore-size distribution.