Sintering of Partially Stabilized Zirconia by Microwave Heating Using ZnO–MnO2–Al2O3 Plates in a Domestic Microwave Oven

Abstract

Partially stabilized zirconia (PSZ) powders were fully densified by microwave heating using a domestic microwave oven. Pressed powder compacts of PSZ were sandwiched between two ZnO–MnO2–Al2O3 ceramic plates and put into the microwave oven. In the first step, PSZ green pellets were heated by self‐heating of ZnO–MnO2–Al2O3 ceramics (1000°C). In the second step, the heated PSZ pellets absorbed microwave energy and self‐heated up to a higher temperature (1250°C), leading to densification. The density of PSZ obtained by heating in the microwave oven for 16 min was 5.7 g/cm3, which was approximately equal to the density of bodies sintered at 1300°C for 4 h or 1400°C for 16 min by the conventional method. The average grain size of the sample obtained by this method was larger than the average grain size of samples sintered by the conventional method with a similar heating process.