面曝光成型薄壁陶瓷BASE管的新型制造方法研究

Beta alumina solid electrolyte tube (BASE Tube) is a key component of energy conversion for high temperature thermoelectric converters. This paper developed a mask projection stereolithography method and transformation method to fabricated the thin-walled BASE tube structure. A special ceramic slurry with alumina and zirconia content of 45vol% is prepared. The slurry curing curve and optimal exposure parameters are analyzed to determine the final printing parameters of the slurry. The thermogravimetric curve analysis is used to develop the degreasing and sintering process route for the ceramic green body. By EDS analysis, Al, O, Zr are the only three elements in the sintered sample. The density and mechanical strength of sintered samples were 95.3% and (352.0 ± 37.5)MPa respectively. The Na₂O is used as the sodium source to explore the phase transformation effect at 1 100℃, 1 200℃, 1 300℃, 1 400℃ and 1 500℃. The results show that there was generation of β″-Al₂O₃ at each temperature section, 1 500℃ was the optimal phase conversion temperature, and the production amount of β″-Al₂O₃ can be achieved at 80.5wt% and the ions conductivity at 450℃ is 7.83×10^-3 S/cm. The effects of phase transformation on sample density, bending strength, and dimensional accuracy were studied. It was found that phase inversion would cause a decrease in sample density. It proved that the feasibility of manufacturing thin-walled BASE tubes by mask projection stereolithography, providing a new manufacturing method for BASE components and low-cost rapid manufacturing of Na⁺ batteries and alkali metal thermoelectric converters.