Micromechanical Deformation

该基金利用原子力显微镜、连续压痕测试和压痕蠕变分析研究微观机械变形。这些技术被应用于多种材料系统（巴基球，非晶金属，聚合物），以开发适用于薄膜的微机械测试的新工具。计划利用原子力显微镜及其配套的小压头进行纳米压痕实验。剪切带在聚合物和非晶金属中进行了检测。理论支持包括考虑巴基球之间相互作用的分子动力学，用压头连续加载和卸载的有限元分析以及铝晶界的扩散蠕变。结果影响了薄膜和小颗粒的微机械测量面积。裂纹成核、侵蚀和局部变形是微变形现象的例子，将受益于改进的分析技术。

This grant investigates micromechanical deformation using atomic force microscopy, continuous indentation testing, and impression creep analysis. These techniques are applied to several materials systems (bucky balls, amorphous metals, polymers) to develop new tools for micromechanical testing applicable to thin films. Nanoindentation experiments are planned using the atomic force microscope and its associated small indenter. Shear bands are examined in polymers and amorphous metals. Theoretical support includes consideration of the molecular dynamics of the interaction between bucky balls, finite element analysis of continuous loading and unloading with an indenter, and diffusional creep at aluminum grain boundaries. %%% The results impact the area of micromechanical measurement of thin films and small particles. Crack nucleation, erosion, and localized deformation are examples of microdeformation phenomena that would benefit from improved analysis techniques.