US Egypt Cooperative Research: Si3N4/SiC Nanocomposites Synthesized from Waste Silica Fume for High Temperature Structural Applications

这项合作研究项目由康涅狄格大学的Leon L. Shaw博士和埃及国家研究中心的Mahmoud Farag Zawrah博士共同承担，研究主题是利用废硅灰生产氮化硅-碳化硅（Si3N4/SiC）纳米复合材料，用于高温应用，如涡轮或发动机部件。废硅灰将被球磨，以减少粒度和实现所需的成分的混合物，与研磨时间为主要变量的调查。为了优化烧结过程中的结果，界面化学的控制将涉及使用和不使用烧结助剂的实验。对于每个得到的样品，将测量蠕变强度、断裂韧性和抗热震性的机械性能。该提案提出了基础材料科学和工程的创造性组合来解决实际问题。这项研究有可能提供有益的结果，例如开发用于燃气轮机推进系统和发电能源系统的高温结构材料。如果成功，这种制备纳米复合材料的过程将导致废物流的有效再利用，并具有显著的环境效益。此外，与埃及科学家的合作带来了互补的技能，以及培训美国和埃及学生的机会。该项目由美国-埃及联合基金项目资助，该项目向两国的科学家和工程师提供赠款，以开展合作研究。

This collaborative research project is being undertaken by Dr. Leon L. Shaw, University of Connecticut, and Dr. Mahmoud Farag Zawrah, National Research Center of Egypt on the topic of using waste silica fume to produce silicon nitride - silicon carbide (Si3N4/SiC) nanocomposites for use in high temperature applications such as turbine or engine components. Waste silica fume will be ball milled in order to reduce particle size and to achieve desired mixture of components, with milling time a primary variable for the investigation. Control of interfacial chemistry will involve experiments with and without sintering aids in order to optimize results during sintering. For each of the resulting samples, mechanical properties of creep strength, fracture toughness, and thermal shock resistance will be measured.The proposal presents a creative mix of basic materials science and engineering to address practical problems. The research has the potential to provide beneficial outcomes such as the development of high temperature structural materials for gas turbine propulsion systems and for power-producing energy systems. If successful, this process of preparing nanocomposites would result in an effective waste stream re-use, with significant environmental benefits. Additionally, the collaboration with Egyptian scientists brings complementary skills, as well as the opportunity for training of both US and Egyptian students.The project is funded under the US-Egypt Joint Fund Program, which provides grants to scientists and engineers in both countries to undertake cooperative research.