Environmental Sensitivity of Diamond-Like Carbon (DLC) Friction and Wear

类金刚石碳 (DLC) 摩擦磨损的环境敏感性

• 批准号: 1131128
• 负责人: Seong Kim
• 金额: $ 32.5万
• 依托单位: Pennsylvania State Univ University Park
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-01 至 2015-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1131128&HistoricalAwards=false
• 关键词: Environmental; Sensitivity; Diamond; Like; Carbon

The research objective of this award is to understand and control the surface properties of diamond-like carbon (DLC) which is a technically important material. Various types of DLC are used to control friction and wear in a wide range of engineering applications due to their superior mechanical and tribological properties. The recent discovery of near-frictionless properties of hydrogenated DLC films can lead to innovations to reduce frictional energy loss and increase the service life of mechanical systems. However, the near-frictionless behavior is observed only in vacuum or extremely dry conditions after an initial induction period during which the friction is initially high and the DLC film surface wears. In atmospheric conditions, near-frictionless DLC films lose their superlubricity and are subject to wear. This research is based on a hypothesis that the DLC surface is highly reactive and can be oxidized in ambient air. Through a series of control experiments and using innovative experimental designs, this research will determine the thickness and composition of the oxidized surface layer in various environments and find vapor additives that can ensure ultra-low friction and wear-free operation of DLC in ambient air conditions.The new hypothesis and experimental findings of this research will have great impacts on not only DLC tribochemistry but also energy-saving technology. This work will change the common view that the DLC surface is inert. The DLC surface is reactive especially in oxygen and humid environments. The deeper understanding of the DLC surface chemistry will eventually help to develop coating technologies for energy conservation through reduction of parasitic frictional dissipation and material loss. Undergraduate students will be involved to analyze how much energy is lost in daily activities around us as well as in industrial places. Graduate students involved in this project will be trained with multidisciplinary skills - chemical engineering, molecular spectroscopy, tribology, and coatings. The spectral data and findings of this research will be incorporated into a graduate-level characterization. The research opportunity will be offered to underrepresented groups.

该奖项的研究目标是了解和控制类金刚石碳（DLC）的表面特性，类金刚石碳是一种技术上重要的材料。各种类型的 DLC 因其卓越的机械和摩擦学性能而被广泛用于控制各种工程应用中的摩擦和磨损。最近发现的氢化 DLC 薄膜的近无摩擦特性可以带来减少摩擦能量损失并延长机械系统使用寿命的创新。然而，只有在真空或极其干燥的条件下才能观察到近乎无摩擦的行为，在初始诱导期之后，在此期间摩擦最初很高并且 DLC 薄膜表面磨损。在大气条件下，近乎无摩擦的 DLC 薄膜会失去超润滑性并容易磨损。这项研究基于这样的假设：DLC 表面具有高反应性并且可以在环境空气中被氧化。通过一系列控制实验并采用创新的实验设计，该研究将确定各种环境下氧化表面层的厚度和成分，并找到能够确保DLC在环境空气条件下超低摩擦和无磨损运行的蒸气添加剂这项研究的新假设和实验结果不仅对DLC摩擦化学而且对节能技术都将产生重大影响。这项工作将改变 DLC 表面是惰性的普遍观点。 DLC 表面尤其在氧气和潮湿环境中具有反应性。对 DLC 表面化学的更深入了解最终将有助于开发涂层技术，通过减少寄生摩擦耗散和材料损失来实现节能。本科生将参与分析我们周围以及工业场所的日常活动中损失了多少能量。参与该项目的研究生将接受多学科技能的培训——化学工程、分子光谱学、摩擦学和涂层。这项研究的光谱数据和发现将被纳入研究生水平的表征中。研究机会将提供给代表性不足的群体。