Ceramics-Silikáty 66, (4) 571 - 578 (2022)

An ultrasonic-assisted resistance sintering furnace was developed by using an integrated crucible to transfer ultrasonic energy to silicate ceramic samples for improving the conventional sintering process. The silicate ceramic samples were prepared and sintered by conventional and ultrasound-assisted sintering processes. The shrinkage, water absorption, bulk density, crystalline phase, and morphology were investigated by using the Archimedes method, X-ray diffraction, and scanning electron microscopy. The results show that the densification and microstructure of the samples can be improved by the ultrasound-assisted sintering at lower sintering temperatures and sintering times. The optimum sintering temperatures in this study were 1160 °C and 1145 °C for the conventional and ultrasound-assisted sintering processes, respectively. The loading of ultrasonic waves in the sintering can homogenise the grain size and grain shape, and make the grain and pore distribution more uniform. The microstructure is remarkably improved at the appropriate sintering temperature and sintering times by ultrasonic-assisted sintering.