ORAL

SESSION: AdvancedMaterialsWedAM-R8	Marquis International Symposium on New and Advanced Materials and Technologies for Energy, Environment and Sustainable Development(3rd Intl Symp. on New and Advanced Materials and Technologies for Energy, Environment and Sustainable Development)
Wed Oct, 25 2017	Room: Maria Luisa & Maria Fernanda
Session Chairs: Dipankar Ghosh; Pengwan Chen; Session Monitor: TBA

12:00: [AdvancedMaterialsWedAM03]
Ice-templated Ceramics and Composites: Understanding Structure-Property Relationships in the Quasistatic and Dynamic Regimes of Compressive Loading
Dipankar Ghosh¹ ; Mahesh Banda¹ ; Hyungsuk Kang¹ ; Sashanka Akurati¹ ; Valere Kamaha¹ ; ¹Old Dominion University, Norfolk, United States;
Paper Id: 244 [Abstract]

Ice-templating is an emerging and versatile technique that can be employed to synthesize advanced macroporous ceramics and multilayered ceramic-polymer composites for various engineering endeavors. In ice-templating of ceramics, typically an aqueous ceramic suspension is unidirectionally frozen that results in the formation of alternate layers of ice and ceramic particles, and freeze drying of the frozen solid yields a macroporous ceramic scaffold that contains directional pores. Usually, the ceramic scaffolds are sintered to gain strength; however, the pore architecture evolved during the solidification step is retained. Due to the low pore tortuosity, scaffolds can be easily infiltrated with a polymer phase to develop multilayered ceramic-polymer composites. To envision the utilization of the ice-templated ceramics and ceramic-polymer composites for the mechanical load bearing applications including the high-strain rate environment, it is imperative to understand their uniaxial compressive mechanical behavior both in the quasistatic and dynamic regimes of strain rates. However, the structure-property (mechanical) relationships of the ice-templated materials are poorly understood, there are only few studies that have attempted to investigate the role of the different length-scale components on the mechanical properties, and high-strain rate studies are almost nonexistent. In this talk, we will first present our recent efforts on the novel developments of the ice-templated alumina ceramic, where we utilized anisotropic grains (platelets) to markedly enhance the uniaxial compressive mechanical response of the sintered scaffolds. Rigorous microstructural investigations revealed unique arrangements of the platelets within and out of the lamella walls, and a transition of the pore morphology occurred with the increasing plateletsO content and the freezing front velocity (FFV). Based on the rigorous microstructural analysis, a novel methodology is developed that estimates the distribution of the platelets within and out of the walls as well as variation of the plateletsO distribution as a function of the composition and the FFV. The measured drastic improvement of the uniaxial compressive mechanical properties is related to the platelets' distribution within and out of the walls and the pore morphology modifications. We will conclude the talk with the preliminary results of the split-Hopkinson pressure bar (SHPB) experiments conducted for both the porous alumina scaffolds and the alumina-epoxy composites.