MCA: Friction of Nanocrystals at Technologically Relevant Speeds: Filling the Gap of Knowledge in Nanotribology

这笔资金将用于开发一种复杂的技术，以确定与齿轮和轴承等工业应用最相关的速度下单个纳米晶体的摩擦。由于滑动表面之间的接触可以建模为纳米级接触的集合，因此该项目对于推进减少摩擦技术至关重要。据估计，摩擦和磨损每年造成的损失高达国内生产总值（GDP）的1.6%，相当于美国的3000多亿美元，因此该项目将促进国家繁荣。这笔拨款还将用于发展一项中学教师培训计划，使他们能够培养科学探究、解决问题的能力，以及对实证工作复杂性的欣赏，这些都是学生在大学水平的科学领域取得成功的关键。该技术将通过集成石英晶体微天平、扫描隧道和原子力显微镜来确定单个纳米晶体在1毫米/秒到1米/秒之间的摩擦。单个纳米晶体的摩擦作为接触面积从1到10,000 nm2的函数将被确定，以建立纳米级摩擦的基本物理，其速度与应用最相关。由合作伙伴进行的计算将加强这些结果的影响。该项目将通过直接将测量的耗散信号与纳米级摩擦连接起来，验证石英晶体微天平的摩擦测量结果。因此，该项目将对纳米摩擦学的纳米力学的发展产生广泛的科学影响。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This grant will enable the development of a sophisticated technique to determine friction of individual nanocrystals at the speeds most relevant for industrial applications such as gears and bearings. Since contacts between sliding surfaces can be modeled as an ensemble of nanoscale contacts, the project is critical for advancing friction reduction technologies. This project will advance the national prosperity since friction and wear are estimated to cost up to 1.6 percent of the GDP per year, corresponding to over $300 billion for the United States. This grant will also enable the development of a middle-school teacher training program to prepare them to foster scientific inquiry, problem solving, and appreciation for the complexity of empirical work, all critical for success of students in college-level sciences.The developed technique will determine friction of individual nanocrystals between 1 mm/sec to 1 m/sec by integrating the quartz crystal microbalance with scanning tunneling and atomic force microscopy. The friction of individual nanocrystals as a function of contact area from 1 to 10,000 nm2 will be determined to establish the fundamental physics of nanoscale friction at the speeds most relevant for applications. Calculations performed by the collaborative partner will strengthen the impact of these results. This project will validate friction measurements using quartz crystal microbalances in general by directly connecting the measured dissipation signals with nanoscale friction. As such, this project will have a broad scientific impact to the advancement of the nanomechanics of nanoscale tribology.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.