Abstract
The design and capabilities of a computer-automated high-spatial-resolution displacement-measurement system are described. The system is used to determine the relative displacement fields generated by thermal or mechanical loads by comparing a pair of SEM or optical micrographs, one recorded before the load is applied and the other afterwards. The displacements are measured by cross-correlation analysis of the relative positions of visible surface texture on the micrographs. Displacement accuracy on a specimen surface is ±60 Ă for optical microscopy, and ±10 Ă for scanning electron microscopy. Both in-plane or out-of-plane deformation can be characterized depending on the angle at which the specimen is viewed. This instrument has the potential of quantifying surface deformation over submicron gage lengths and will be an invaluable tool in experimental micromechanics.
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James, M.R., Morris, W.L. & Cox, B.N. A high accuracy automated strain-field mapper. Experimental Mechanics 30, 60–67 (1990). https://doi.org/10.1007/BF02322704
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DOI: https://doi.org/10.1007/BF02322704