The application of electrostatic fields during processing of oxide ceramic microstructures was previously reported to enhance densification and grain growth. In this study effects of the externally applied electrostatic field strength on grain growth in MgAl₂O₄ were investigated. Free sintering of green bodies showed accelerated grain growth by about 20% in the presence of an applied nominal field strength of 0.95 kV/cm. In contrast to previous studies, annealing of dense microstructures in the presence of a nominal electric field strength as high as 2.22 kV/cm revealed no additional grain growth. A machine learning algorithm for grain size analysis enabled grain size distributions including up to 30,000 grains. Due to the resulting counting statistics for microstructure analysis, it was discovered that the applied electrostatic fields caused grain growth predominantly during the early stages of sintering, i.e., at lower green body densities, hence suggesting an enhancement of surface diffusion.

先前已报道在氧化物陶瓷微结构的加工过程中施加静电场可增强致密性和晶粒长大。在这项研究中，外部施加的静电场强度对MgAl ₂ O _4中晶粒生长的影响被调查了。在施加的额定场强为0.95 kV / cm的情况下，生坯的自由烧结显示出晶粒加速了约20％的生长。与以前的研究相反，在存在高达2.22 kV / cm的标称电场强度的情况下，对致密的微观结构进行退火显示没有额外的晶粒生长。一种用于粒度分析的机器学习算法可实现粒度分布，包括多达30,000个晶粒。由于得到的用于微观结构分析的计数统计数据，发现施加的静电场主要在烧结的早期阶段（即在较低的生坯密度下）导致晶粒生长，因此表明表面扩散得到增强。