Use of Digital Images to Determine Deformation Throughout a Microstructure. Part 1. Deformation Mapping Technique.
Use of Digital Images to Determine Deformation
Throughout a Microstructure. Part 1. Deformation
Neubauer, C. M.; Garboczi, E. J.; Jennings, H. M.
Journal of Materials Science, Vol. 35, 5741-5749, 2000.
Materials with heterogeneous microstructures do not
deform uniformly under stress (mechanical or
environmental). A new deformation mapping technique
(DMT), which compares digital images of microstructures
of the same field of view before and after deformation
occurs, is reported. Two digital images are required: a
reference image, taken before deformation; and a
deformed image, taken after deformation. The
displacements of pixels required to match the deformed
image to the reference image are computed, and these
displacements are used to calculate the percent
deformation in the two principal directions. Results are
presented as either a deformation map, as a histogram,
or as data files containing the displacements at the
corner of each pixel. Comparison with exact solutions
generated on a simulated microstructure shows that the
accuracy of this technique is quite good.