Examination of Tool Marks in the Scanning Electron Microscope
Examination of tool marks in cases relating to theft, burglary, violence and other criminal offenses is frequently carried out by a forensic scientist. Tool marks are produced on a softer surface by a tool of harder material, while commissioning a crime. The tool is not damaged in the process of cutting or scratching the surface of the material to any appreciable extent. The marks on the surface are reproducible. Thus, a criminal can be linked to a crime through the examination of the tool recovered from the criminal and the tool marks collected from the scene. Although the marks of fairly large size (over a few microns) can be seen under an optical microscope with an optimal magnification of 2000X, the marks of smaller dimensions (below one micrometer) can not be revealed. This is a situation where the application of the scanning electron microscope is called upon.
KeywordsSurface Irregularity Aluminum Wire Tool Mark Indentation Mark Fine Striation
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