CAREER: The Dependence of Friction on Vibrations at the Atomic Scale: A Fundamental Study Using Isotopic Engineering

职业：原子尺度上摩擦对振动的依赖性：利用同位素工程的基础研究

• 批准号: 0134571
• 负责人: Robert Carpick
• 金额: $ 37.5万
• 依托单位: University of Wisconsin-Madison
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-01-15 至 2006-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0134571&HistoricalAwards=false
• 关键词: CAREER; Dependence; Friction; Vibrations; Atomic

CAREER: The Dependence of Friction on Vibrations at the Atomic Scale: A Fundamental Study Using Isotopic Engineering Robert W. Carpick University of Wisconsin - Madison Research Much progress has been made in the long-standing engineering discipline of tribology - the study of friction, adhesion, lubrication, and wear - yet many key questions remain. Recently, tribology has emerged as critically important to the field of nanotechnology, since the increased surface-to-volume ratio at small scales ensures that surface or interface effects dominate the interactions between micro- or nano-scale components. Therefore, progress toward the implementation of nano-scale materials technologies will not occur without a fundamental atomic-scale understanding of the tribological properties of interfaces. The proposed research will address this knowledge gap by studying a fundamental aspect of tribology: the relationship between frictional energy dissipation and the vibrational properties of materials. Specifically, the PI will perform atomic force microscope (AFM) measurements of friction at the atomic scale as a function of isotopic composition of the sliding materials. The substitution of heavier stable isotopes is a method to tailor specific vibrational properties by changing the mass, but not the chemical identity, of atoms in a material. The impact of this research will be: (1) to provide a quantitative experimental basis that will critically enhance the theoretical understanding of frictional energy dissipation in terms of vibrational energy; and (2) to enable the design of nanostructured materials and devices with optimized tribological (and other) properties via isotopic engineering. Education and Outreach To be prepared for new opportunities in nanotechnology, engineering programs must incorporate previously non-traditional physical and experimental concepts into the curriculum. The PI will make a major contribution to this by: (1) expanding an engineering mechanics undergraduate laboratory course to include a battery of nano-scale experiments including AFM experiments; and (2) co-developing an advanced seminar course in nanotechnology directed at engineers. The intention is not simply to provide new course materials locally, but to have these materials serve as models for enhancing engineering curricula everywhere through evaluation and wide dissemination on the web, education publications, and in public meetings. In addition, outreach efforts aimed at the general public and K-12 students will be pursued. The PI will contribute to the design of an upcoming international science museum exhibit on materials science by developing modules (visualization, models, hands-on materials) on the topics of microscopy, friction, and isotopes. The PI will also develop a classroom-compatible macro-scale AFM made of simple and affordable components which can demonstrate concepts behind high resolution imaging and friction force measurements. Local impact of this work will be felt through the PI's active involvement in a successful minority university recruiting program at UW-Madison. Finally, building on the established practice in the PI's lab, the laboratory efforts will also include substantial involvement of undergraduates including members of underrepresented groups.

在原子尺度上摩擦对振动的依赖性：使用同位素工程的基础研究。威斯康星州-麦迪逊的Carpick大学研究摩擦学这一历史悠久的工程学科--摩擦、粘附、润滑和磨损的研究--已经取得了很大的进展，但仍然存在许多关键问题。最近，摩擦学已经成为纳米技术领域的关键，因为在小尺度上增加的表面积与体积比确保了表面或界面效应主导了微米或纳米尺度组件之间的相互作用。因此，如果没有对界面摩擦学性质的基本原子尺度的理解，纳米材料技术的进展就不会发生。 拟议的研究将通过研究摩擦学的一个基本方面来解决这一知识缺口：摩擦能量耗散与材料振动特性之间的关系。具体而言，PI将在原子尺度上对摩擦进行原子力显微镜（AFM）测量，作为滑动材料同位素组成的函数。较重稳定同位素的取代是一种通过改变材料中原子的质量而不是化学特性来定制特定振动特性的方法。这项研究的影响将是：（1）提供定量的实验基础，这将极大地提高对振动能量方面摩擦能量耗散的理论理解;（2）通过同位素工程设计具有优化摩擦学（和其他）特性的纳米结构材料和器件。为了迎接纳米技术的新机遇，工程专业必须将以前非传统的物理和实验概念纳入课程。PI将通过以下方式对此做出重大贡献：（1）扩大工程力学本科实验室课程，包括一系列纳米级实验，包括AFM实验;以及（2）共同开发针对工程师的纳米技术高级研讨会课程。其目的不仅仅是在当地提供新的课程材料，而是通过评估和在网络、教育出版物和公共会议上广泛传播，将这些材料作为加强各地工程课程的模式。此外，还将开展针对公众和K-12学生的外联工作。PI将通过开发关于显微镜，摩擦和同位素主题的模块（可视化，模型，实践材料），为即将到来的国际科学博物馆材料科学展览的设计做出贡献。PI还将开发一种课堂兼容的宏观尺度AFM，由简单且价格合理的组件制成，可以演示高分辨率成像和摩擦力测量背后的概念。这项工作的本地影响将通过PI在威斯康星大学麦迪逊分校成功的少数民族大学招聘计划的积极参与而感受到。最后，在PI实验室既定实践的基础上，实验室工作还将包括本科生的大量参与，包括代表性不足群体的成员。