Effect of surfaces, internal and external, on the strength and ductility of metals

现代微电子和微机械设备包含微小的微米级，通常是亚微米级大小的金属部件。与体积较大的金属部件相比，这些部件的强度显著提高。描述其独特性质的理论往往与描述经典块状金属部件的强度的理论大不相同，尽管这两种情况下的金属是相同的。金属的塑性变形，在所有的长度尺度上，强烈地受到变形金属周围的外表面和内部表面的条件的影响。这项拟议的研究将通过考虑各种类型的内外表面对变形过程的相对影响来探讨金属的长度尺度相关塑性变形这一主题。这样，对塑性变形过程的统一理解将大大提高我们对现有的和新的金属部件的机械强度和延展性的预测能力，无论其尺寸如何。

Modern microelectronic and micromechanical devices contain tiny micrometer, and often submicrometer, size metal components. These components display significantly increased strength compared to their larger bulk metal counterparts. Theories describing their unique properties are often quite different than those describing the strength of classical bulk metal components despite the fact that the metal is the same in both cases. The plastic deformation of metals, across all length scales, is strongly influenced by the condition of the external surface around, and internal surfaces within, the deforming metal. This proposed study will approach the subject of length-scale dependent plastic deformation of metals by considering the relative influence of a variety of types of internal and external surfaces on the deformation process. In this way a unified understanding of the plastic deformation process will be arrived at that will greatly improve our predictive capability of the mechanical strength and ductility of existing, and new, metal components regardless of their size.