Microwave Sintering of Partially Stabilized Zirconia Using a Domestic Microwave Oven

利用家用微波炉对部分稳定氧化锆粉进行微波加热，使其完全致密化。将压制好的PSZ粉末压坯夹在两片ZMA陶瓷板之间，在微波炉中预热，然后放入烤箱。用家用微波炉加热16min制得的PSZ陶瓷的密度为5.94g/cm3，与传统的炉法在1350℃下烧成4h或1400℃下烧成16min的密度大致相当。用ZMA陶瓷预热的PSZ芯块更容易吸收微波能量并自我加热到更高的温度。微波加热不仅提高了致密化，而且还促进了晶粒的长大。微波烧结的抗弯强度与常规烧结法相当(1450℃，4h)。从这一点上可以看出，这种用家用微波炉进行烧结的方法比传统的低能耗、低成本的方法要好得多。用家用微波炉加热11min，得到致密的样品。采用烧结碳化硅作为预热器。

Partially stabilized zirconia (PSZ) powders were fully densified by microwave heating using a domestic microwave oven. The pressed powder compacts of PSZ were sandwiched between two ZnO-MnO_2-Al_2O_3 (ZMA) ceramic plates acting as preheaters in the microwave oven and put in the oven. PSZ ceramics fabricated with the domestic microwave oven for 16 min exhibited a density of 5.94 g/cm^3, which is approximately equal to the density of bodies sintered at 1350 ℃ for 4 h or at 1400 ℃ for 16 min by the conventional furnace method. The PSZ pellet pre-heated by the ZMA ceramics more easily absorbed the microwave energy and self-heated to a higher temperature. The microwave heating enhanced not only the densification but also the grain growth. From this viewpoint, it was judged that the atomic diffusion should be promoted by irradiation of the microwave.The bending strength of specimens sintered by microwave heating was comparable with that sintered by a conventional method (1450 ℃, 4 h). From this viewpoint, it is judged that this sintering method using an domestic microwave oven is better than the conventional method for the low energy consumption and low cost.The similar method was applied on the sintering of lead zirconate titanate (PZT). The dense specimens were obtained for 11 min of driving a domestic microwave oven. Sintered silicon carbide was used as a preheater.