Effects of sintering temperature on pore characterization and strength of porous corundum-mullite ceramics

Effects of sintering temperature on pore characterization and strength of porous corundum-mullite ceramics

The effects of sintering temperature on the pore characteristics and strength of porous corundum-mullite ceramics made from Al(OH)3, kaolinite gangue and MgCO3 were investigated through an X-ray diffractometer (XRD), scanning electron microscopy (SEM), mercury porosimetry measurement, etc. It was found that the sintering temperature strongly affects the formation of secondary mullite, and then changes the pore characteristics and strength. The formation of secondary mullite takes place extremely quickly at 1500 oC. The pore size distributions are bimodal in samples sintered at 1300 oC and 1400 oC,and mono-modal in samples sintered at 1500 oC and 1600 oC. The strength are the same and low when the sintering temperatures are 1300 oC and 1400 oC, and increase sharply when the sintering temperature is increased to 1500 oC. The most apposite mode is a sample sintered at 1500 oC which has a high mullite content (86.6 wt%), high apparent porosity (42%), high crushing strength (52 MPa) and a homogeneous pore size distribution.

The effects of sintering temperature on the pore characteristics and strength of porous corundum-mullite ceramics made from Al(OH)3, kaolinite gangue and MgCO3 were investigated through an X-ray diffractometer (XRD), scanning electron microscopy (SEM), mercury porosimetry measurement, etc. It was found that the sintering temperature strongly affects the formation of secondary mullite, and then changes the pore characteristics and strength. The formation of secondary mullite takes place extremely quickly at 1500 oC. The pore size distributions are bimodal in samples sintered at 1300 oC and 1400 oC,and mono-modal in samples sintered at 1500 oC and 1600 oC. The strength are the same and low when the sintering temperatures are 1300 oC and 1400 oC, and increase sharply when the sintering temperature is increased to 1500 oC. The most apposite mode is a sample sintered at 1500 oC which has a high mullite content (86.6 wt%), high apparent porosity (42%), high crushing strength (52 MPa) and a homogeneous pore size distribution.