A Novel Method for Manufacturing Ceramic-Reinforced Metal Matrix Composites Using Liquid Metal Processing

众所周知，运输车辆的更高能源效率可以通过减轻部件重量来实现。减轻车辆重量的一种有效方法是用新型轻质材料取代结构部件中的黑色金属，这种材料在环境和高温下都表现良好，例如陶瓷增强金属基复合材料。增强体的小尺寸和均匀分布对复合材料的力学性能至关重要，但大多数工艺都不能达到有效水平。该奖项支持研究利用液态金属加工制造纳米陶瓷增强金属基复合材料的新工艺。这种新型节能工艺将克服当前的加工挑战，并有可能制造出具有非凡性能的复合材料。通过与工业界的直接合作，从这项工作中产生的知识、材料和处理协议将很容易实现。该研究介绍了一种利用液态金属加工制造金属基纳米陶瓷复合材料的新方法，其中使用聚合物前驱体直接在熔融金属中产生陶瓷增强。与传统的铸造方法不同，纳米陶瓷颗粒在加工过程中被添加并混合到金属中，这里要研究的原位特征提供了几个潜在的优势。这些包括纳米级陶瓷颗粒的均匀分布，良好结合的颗粒-金属基体界面，广泛的金属-陶瓷系统选择，以及加工过程中的能源和成本节约。该工艺已被证明是可行的，但负责材料纳米结构和由此产生的性能的基本机制尚未很好地确定。本研究将通过系统的实验研究来了解纳米陶瓷颗粒形成的机制，评估其在高温下的行为和稳定性，并制定有效的加工方案和优化的微观结构，从而填补知识空白。此外，这项工作将建立微观结构和机械性能之间的关系，包括疲劳，这是在运输行业的关键结构应用中部署新型金属基纳米复合材料所需要的。

It is well known that higher energy efficiencies in transportation vehicles can be achieved through component weight reduction. An effective method to reduce vehicle weight is to replace ferrous metals in structural components with novel lighter weight materials that perform well at both ambient and elevated temperatures, such as ceramic-reinforced metal matrix composites. Both small size and uniform distribution of the reinforcement are critical for the mechanical performance of a composite material yet most processes do not produce an effective level for either. This award supports research into a new process for manufacturing nano-ceramic reinforced metal matrix composites using liquid metal processing. This new and energy efficient process will overcome current processing challenges and potentially enable fabrication of composite materials with extraordinary properties. Through direct collaborations with industry, the knowledge, materials, and processing protocols emerging from this work will be readily implemented. The research introduces a novel method for manufacturing metal matrix nano-ceramic composites using liquid metal processing, where the ceramic reinforcement is directly created in the molten metal using a polymer precursor. Unlike conventional casting methods where the nano-ceramic particles are added and mixed into the metal during processing, the in-situ feature to be studied here offers several potential advantages. These include uniform distributions of nano-scale ceramic particles, well-bonded particle-metal matrix interfaces, broad selection of metal-ceramic systems, and energy and cost savings during processing. The process has been demonstrated to be feasible but the fundamental mechanisms responsible for the material nanostructure and resulting properties are not well established. This research will fill the knowledge gap through systematic experimental studies to understand the mechanisms driving the formation of the nano-ceramic particles, evaluate their behavior and stability at elevated temperatures, and develop effective processing protocols and optimized microstructures. In addition, the work will establish relationships between microstructure and mechanical properties, including fatigue, that are needed to deploy the new metal matrix nano-composites in critical structural applications for the transportation industries.