Remapping

Infinitesimal strain theory does not apply where the measured lattice rotations are large. Remapping is a procedure introduced to remove large rotations to allow infinitesimal strain theory to then be used to measure elastic strain values. Remapping is necessary where primary measured rotations are greater than 1 degree.

With remapping, the initially measured rotation is used to back rotate each pixel within each ROI to present the EBSD pattern without the rotation. A second XCF pass is then performed to obtain the improved measure of the strain tensor. In practice, remapping is conducted at the subpixel level which effectively takes into account the change in pixel shape produced by the rotation.

                                                           1st pass XCF processing strain results                                                     2nd pass Remapped strain results

Fig 1. E11 Normal Strain Sample Axis

HR EBSD measurements of a single grain of Titanium showing how Remapping removes the interference of lattice rotations in strain measurements