Governing role of the ratio of large platelet particles to ultrafine particles on dynamic and quasistatic compressive response and damage evolution in ice-templated alumina ceramics

This study revealed that the mass ratio of large anisometric particles (platelets) to ultrafine, equiaxed particles strongly influences dynamic and quasistatic compressive response and the process of damage evolution in ice-templated alumina materials. The improved sinterability between particles of significantly dissimilar size and morphology enabled the utilization of a high mass ratio of the particles in harnessing a markedly enhanced level of strength in highly porous ice-templated ceramics. The high volume fraction of platelets increased lamellar bridge density and resulted in dendritic morphology as opposed to lamellar morphology without platelets. All the materials showed strain rate-sensitivity, where strength increased with strain rate. Materials with highly dendritic morphology exhibited the best performance in terms of maximum strength and energy absorption capacity, and the performance improved from quasistatic to dynamic regime. Direct observation of the process of damage evolution revealed the effects of both strain rate and ratio of platelets to ultrafine particles.

本研究揭示了大型各向异性颗粒（如血小板）与超细等轴颗粒的质量比显著影响冰模板氧化铝材料在动态和准静态压缩响应以及损伤演化过程中的行为。显著不同尺寸和形态的颗粒之间烧结性的提升，使得在利用高颗粒质量比提升高度多孔冰模板陶瓷的显著强度水平时成为可能。高体积分数的血小板增加了层状桥密度，并导致出现树枝状形态而非无血小板的层状形态。所有材料均表现出应变率敏感性，即随着应变率的增加，强度也随之提高。具有高度树枝状形态的材料在最大强度和能量吸收能力方面表现出最佳性能，其性能从准静态向动态状态过渡。对损伤演化过程的直接观察揭示了应变率和血小板与超细颗粒比率的共同影响。