The mechanism in bio-materials by multi-scale strain measurement

通过现场场发射扫描显微镜(FE-SEM)的观察，研究了在纳米到毫米的多尺度范围内变形和应变分布的测量方法。研制了一种专用加载装置，并将其安装在FE-SEM腔体中。基于电子光刻技术，研制了一种由栅格图案、随机团簇图案和纳米团簇图案组成的多尺度图形，用于测量界面不同尺度上的局域变形。将多尺度测量方法应用于混杂碳纤维和珍珠层贝壳等层状微结构材料，对其加载过程中的力学特性进行了评价。显然，本研究可以用来提供在不同长度尺度上发展梯度连续塑性所需的多个长度尺度上的变形行为及其相关的边界条件，以理解分层结构材料。

The measurement method on deformation and strain distribution in a multi-scale range from nanometers to millimeters was investigated by in situ Field Emission Scanning Microscope(FE-SEM) observations. A special loading device was developed and installed into FE-SEM chamber. A multi-scale pattern composed of a grid as well as random and nano-cluster pattern was developed based on electron lithography technique to measure the localized deformation around the interfaces at different scales. The multi-scale measurement method was applied to hierarchical microstructure materials such as hybrid CFRP and Nacre form sea shell to evaluate the mechanical characterization during loading. It is clear that the present study can be used to provide the deformation behaviors at multiple length scales and its related boundary conditions needed for developing a gradient continuum plasticity at different length scales for understanding hierarchical structure materials.