Grain growth kinetics of dense 3 mol. % yttria-stabilized zirconia (3YSZ) ceramics during both DC flash sintering and conventional annealing were investigated using the grain size as a marker of microstructure evolution. The results indicated faster grain growth under greater current density. In contrast to conventionally annealed specimen, the grain boundary mobility was enhanced by almost two orders of magnitude with the applied electric current, revealing that joule heating alone was not sufficient to account for the experimental results. Instead, activation energy for grain growth decreased significantly due to electro-sintering. Systematic characterization of graded microstructure further indicated that local oxygen vacancies and specimen temperature were responsible for a grain size transition. Based on electrochemical reaction involved in flash sintering, grain size reduction at the cathode was proposed to be attributed to the local rearrangement of lattice cations and generated oxygen ions.

3 mol的晶粒生长动力学。使用晶粒尺寸作为微结构演变的标志，研究了在直流闪速烧结和常规退火过程中，氧化钇稳定的氧化锆（3YSZ）陶瓷的百分含量。结果表明在更大的电流密度下晶粒生长更快。与常规退火的试样相反，施加的电流使晶界迁移率提高了几乎两个数量级，这表明仅靠焦耳加热不足以说明实验结果。相反，由于电烧结，用于晶粒生长的活化能显着降低。分级显微组织的系统表征进一步表明，局部氧空位和样品温度是晶粒尺寸转变的原因。