Microscopic strain mapping based on digital image correlation

A novel microscopic strain mapping technique based on digital image correlation has been developed in recent years for various applications in materials characterization. The input is a series of scanning electron microscopy (SEM) images. The method uses topographic features found in these images as the input. A commercially available optical strain measurement system (ARAMIS®) which utilizes the DIC methodology is used for this purpose. Several aspects of technique have been carefully assessed in this paper. Emphasis has been placed on the preparation of samples for SEM observations such as the effect of etching on the image quality in order to achieve the best possible accuracy of the strain mapping results. © 2008 Society for Experimental Mechanics Inc.