MRI: Acquisition of Ultrasonic C-Scan System for Research and Educational Training in Structural Nanocomposites

MRI：获取超声波 C 扫描系统，用于结构纳米复合材料的研究和教育培训

• 批准号: 0521158
• 负责人: Mahesh Hosur
• 金额: $ 26.04万
• 依托单位: Tuskegee University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-09-01 至 2008-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0521158&HistoricalAwards=false
• 关键词: MRI; Acquisition; Ultrasonic; Scan; System

In the last few years nanocomposites have emerged as the new class of materials which are likely to revolutionize the future structural components. These nanocomposites which consist of polymers with nanometer-sized particles have exhibited considerable improvements in chemical, thermal, mechanical properties in addition to improved barrier properties. It is all the more fascinating that these improvements occur at a very low loading percentage of nanoparticles. Researchers at Tuskegee University's Center for Advanced Materials have successfully incorporated a variety of nanoparticles with thermosetting and thermoplastic polymers and extended the concept to manufacture structural nanocomposites. Through this approach they have achieved enhancements in strength and stiffness over their neat polymeric composites. In this major research instrumentation proposal, we are seeking to acquire a state-of-the-art ultrasonic C-scan system to assist and enhance the quality of various aspects of the ongoing research projects funded by NSF, ARO, ONR and EPSCoR. A large number of African-American students, both at undergraduate and graduate level with many at Ph.D. level, will be trained in nondestructive characterization of new class of materials, structural nanocomposites. It is only expected that many younger minority students will be encouraged to take up graduate studies when exposed to state-of-the-art facilities like the proposed ultrasonic C-scan system at early stages of their science and engineering education.Structural nanocomposites have potential to become materials of the future as they have potential to have higher strength and stiffness as compared to current generation fiber reinforced composite materials. Most of the research carried out to date on nanocomposites is focused on the improvement of properties of nanophased matrix systems. In the ongoing research work at Tuskegee University Center for Advanced Materials (T-CAM), attempts are being made to model, synthesize, manufacture and characterize nanophased structural composites. Any such development requires techniques to evaluate elastic properties, defects and damages during manufacture and under different loading conditions using nondestructive evaluation (NDE) techniques. Through this proposal, we are planning to acquire a state-of-the-art ultrasonic nondestructive evaluation (NDE) system. Using this facility, it is planned to understand the cure kinetics using velocity and attenuation measurements through ultrasonic means, optimize the process of fabrication of structural nanocomposites using VARIM process, quantify fabrication defects, evaluate the elastic properties of new class of nanophased composites through nondestructive means, determine the degradation of nanophased composites when subjected to environmental conditioning, evaluate the progressive growth of damages during fatigue loading, estimate the damage due to low-velocity and ballistic impact loading and evaluate the defects induced during the fabrication of integral skin-stringer assembly by VARIM process and isogrid cylinders by filament winding. We propose to characterize, by means of ultrasonic NDE, different class of nanocomposites that are made using various types of nanoparticles, resin systems and fibers. Finally, through this program, a large number of African-American students, both at undergraduate and graduate level with many at Ph.D level, will be trained in nondestructive characterization of new class of materials: structural nanocomposites.

在过去的几年里，纳米复合材料已经成为一种新型材料，可能会给未来的结构部件带来革命性的变化。这些纳米复合材料由纳米级聚合物和纳米级粒子组成，在化学、热、机械性能方面都有很大的改善，而且屏障性能也得到了改善。更令人着迷的是，这些改进发生在极低的纳米颗粒加载百分比下。塔斯基吉大学先进材料中心的研究人员已经成功地将各种纳米颗粒与热固性和热塑性聚合物结合起来，并将这一概念扩展到制造结构纳米复合材料。通过这种方法，他们已经实现了强度和刚度比纯聚合物复合材料的增强。在这项主要的研究仪器提案中，我们正在寻求获得最先进的超声c扫描系统，以协助和提高由NSF， ARO， ONR和EPSCoR资助的正在进行的研究项目的各个方面的质量。大量的非裔美国学生，包括本科生和研究生，以及许多博士，将接受新型材料结构纳米复合材料无损表征方面的培训。只有当许多年轻的少数民族学生在他们的科学和工程教育的早期阶段接触到最先进的设备，如提议的超声波c扫描系统时，才会被鼓励去读研究生。与现有的纤维增强复合材料相比，结构纳米复合材料具有更高的强度和刚度，因此具有成为未来材料的潜力。迄今为止，对纳米复合材料的研究主要集中在改善纳米相基体体系的性能上。在塔斯基吉大学先进材料中心（T-CAM）正在进行的研究工作中，正在尝试对纳米相结构复合材料进行建模、合成、制造和表征。任何这样的发展都需要使用无损评估（NDE）技术来评估制造过程中和不同载荷条件下的弹性性能、缺陷和损伤。通过这项提案，我们计划获得最先进的超声波无损评估（NDE）系统。利用该设施，计划通过超声波测量速度和衰减来了解固化动力学，利用VARIM工艺优化结构纳米复合材料的制造工艺，量化制造缺陷，通过非破坏性手段评估新型纳米相复合材料的弹性性能，确定纳米相复合材料在环境条件下的降解。评估了疲劳加载过程中损伤的渐进增长，评估了低速和弹道冲击载荷造成的损伤，评估了采用VARIM工艺制造整体蒙皮杆组件和采用长丝缠绕工艺制造等网格圆柱体时产生的缺陷。我们建议用超声波无损检测的方法来表征由不同类型的纳米颗粒、树脂体系和纤维制成的不同类别的纳米复合材料。最后，通过这个项目，大量的非裔美国学生，包括本科生和研究生，以及许多博士，将接受关于新型材料的无损表征的培训：结构纳米复合材料。