Ambient Temperature Measurements of Surface Diffusivity and Surface Free Energy Using the Scanning Tunneling Microscope

使用扫描隧道显微镜测量表面扩散率和表面自由能的环境温度

• 批准号: 9011047
• 负责人: Karl Sieradzki
• 金额: $ 4.88万
• 依托单位: Johns Hopkins University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1990
• 资助国家: 美国
• 起止时间: 1990-08-01 至 1991-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9011047&HistoricalAwards=false
• 关键词: Ambient; Temperature; Measurements; Surface; Diffusivity

Surface diffusivity and surface free energy of metals are important physical quantities in phenomena such as nucleation and growth, corrosion, and fracture. Values of these parameters appropriate for ambient temperature behavior are based on linear extrapolations of high temperature measurements. This program examines a new measurement technique for direct observation of surface mobilities using the scanning tunneling microscope. Such measurements need to be done on extremely well characterized surfaces, taking into account surface segregation and effect of electrolyte composition. Consideration of temperature dependence of the surface parameters is considered high risk as it requires new scanning tunneling microscopy techniques.

金属的表面扩散率和表面自由能是形核和生长、腐蚀和断裂等现象中的重要物理量。 这些适合环境温度行为的参数值基于高温测量的线性外推。 该程序研究了一种使用扫描隧道显微镜直接观察表面迁移率的新测量技术。 此类测量需要在特征非常明确的表面上进行，并考虑表面偏析和电解质成分的影响。 考虑表面参数的温度依赖性被认为是高风险的，因为它需要新的扫描隧道显微镜技术。