SGER: High Volume Fraction Aluminum Nanocomposites with Optimized Microstructures

该项目探索了高体积分数纳米氧化铝增强铝的合成和加固，从而生产出具有独特微观结构的复合材料，其中包括类似纳米通道的形态。由于颗粒间距相对较小，加之增强体的体积分数较高，这些材料有望表现出优异的力学性能。一个主要的目标是以经济的方式获得均匀的、高体积分数的纳米级增强体分散。Al-Al_2O_3粉末将机械合金化，然后进行热等静压。用X射线衍射仪、扫描电子显微镜和透射电子显微镜对机械合金化粉末和固结复合材料进行了分析。复合材料将使用常规机械测试、中子衍射和仪表化纳米压痕进行机械表征。结构和力学表征有望在这种复合材料体系中确定优化的微观结构。虽然到目前为止还没有合成这种复合材料，但根据目前对增强机理的了解，这些复合材料有望具有优异的力学性能。这项研究有望导致合成一类新的复合材料。研究活动将与教育相结合，更新本科教学实验室课程的内容，从而使本科生了解复合材料领域的最新发展。

The project explores synthesis and consolidation of aluminum reinforced with a high volume fraction of nano-alumina, thereby producing a composite with a unique microstructural configuration that includes a nano-channel like morphology. Because of the relatively small inter-particle spacing combined with higher volume fraction of the reinforcement, these materials are expected to exhibit superior mechanical properties. A major objective is to obtain a uniform, high volume fraction, nano-sized dispersion of the reinforcement in an economical way. Aluminum-alumina powders will be mechanically alloyed followed by subsequent hot-isostatic pressing. The mechanically alloyed powders and the consolidated composites will be examined using x-ray diffraction, scanning electron and transmission electron microscopy. The composites will be mechanically characterized using conventional mechanical testing, neutron diffraction, and instrumented nanoindentation. Structural and mechanical characterization is expected to result in identifying optimized microstructures in such composite systems.While such composites were not synthesized to-date, based on the current understanding of strengthening mechanisms, these composites are expected to possess superior mechanical properties. The research is expected to lead to the synthesis of a new class of composites. The research activities will be integrated with education in updating the content of an undergraduate instruction laboratory course, thereby making undergraduate students aware of recent developments in the area of composite materials.