NER: Synthesis of Metal Matrix-Nanoparticle Composites by Stir Mixing

NER：通过搅拌混合合成金属基体-纳米粒子复合材料

• 批准号: 0304262
• 负责人: Pradeep Rohatgi
• 金额: $ 7.99万
• 依托单位: University of Wisconsin-Milwaukee
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-07-01 至 2007-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0304262&HistoricalAwards=false
• 关键词: NER; Synthesis; Metal; Matrix; Nanoparticle

This project will explore the synthesis of metal-matrix nanoparticle composites using solidification processes, including stir mixing technique. In the synthesis of the composites using the stir mixing process, there will be uncertainties such as difficulty in the introduction and dispersion of nanosize particles, increase in viscosity in melts due to high surface area of nanosize particles, and flotation/sedimentation velocities of nanosize particles. The incorporation of nanoparticles can lead to metal-matrix nanocomposites with improved mechanical properties, including high strength, high fatigue and high creep properties.In this research, mixing technologies will be developed to mix nanosize particles in aluminum melts, and optimum solidification process will be identified for obtaining a uniform distribution of nanosize particles in cast materials. Mixing conditions, including feeding rate of nanosize particles, stirrer speed, particle volume fraction, wetting agent, ultrasonic energy, and melt temperature will be optimized for a uniform distribution of nanosize particles. The fluidity of a melt containing nanosize particles and velocities of flotation or settling of nanosize particle will also be determined from the final distribution of the particles in the melt and in the matrix. The solidified microstructure and the distribution of nanoparticles in the matrix will be analyzed to understand nucleation and growth behavior in the presence of nanosize particles. Selected properties, including the density, modulus and compressive properties will be measured related to processing variables. It is anticipated that the results of this work can lead to technology transfer for nanocomposite castings.

本项目将探索利用凝固工艺合成金属基纳米颗粒复合材料，包括搅拌混合技术。在采用搅拌混合工艺合成复合材料的过程中，存在纳米颗粒难以引入和分散、纳米颗粒表面积大导致熔体粘度增加、纳米颗粒浮选/沉降速度快等不确定性。纳米颗粒的掺入可以使金属基纳米复合材料具有更好的机械性能，包括高强度、高疲劳和高蠕变性能。在本研究中，将开发混合技术，在铝熔体中混合纳米颗粒，并确定最佳凝固工艺，以获得纳米颗粒在铸造材料中的均匀分布。为了使纳米颗粒均匀分布，将优化纳米颗粒的混合条件，包括进料速度、搅拌速度、颗粒体积分数、润湿剂、超声能量和熔体温度。含有纳米颗粒的熔体的流动性以及纳米颗粒的浮选或沉降速度也将根据颗粒在熔体和基体中的最终分布来确定。通过分析凝固组织和纳米颗粒在基体中的分布，了解纳米颗粒存在下的成核和生长行为。所选的性能，包括密度，模量和压缩性能将测量相关的加工变量。预计这项工作的结果可以导致纳米复合材料铸件的技术转移。