Orientation averaging of electron backscattered diffraction data

The use of data averaging to improve the angular precision of electron back scattered diffraction (EBSD) maps is discussed. It is shown that orientatio ns may be conveniently and rapidly averaged using the four Euler-symmetric parameters which are coefficients of a quaternion representation. The proce ssing of EBSD data requires the use of an edge preserving filter and a modi fied Kuwahara filter has been successfully implemented and tested. Three pa sses of such a filter have been shown to reduce orientation noise by a fact or of similar to 10. Application of the method to deformed and recovered al uminium alloys has shown that such data processing enables small subgrain m isorientation (<0.5<degrees>) to be detected reliably.