I am surprised that you are able to use Channel5 for the analysis of strain. From my point of view Channel5 is only able to visualize lattice orientations or misorientations with respect to a reference orientation which can be an arbitrary orientation, a mean orientation of a grain, or a mean orientation within a kernel. Of course, the visualization can use either the misorientation angle, or the misorientation axis (axis of rotation). As far as I know Channel5, only the misorientation angle is used.

A extraction of lattice strain is theoretically only possible using high resolution patterns. Image correlation techniques enable an evaluation of visible distortions in the scale of parts of a pixel. During this procedure simple rigid body rotations as visible in EBSD orientation maps are even subtracted out in order to process only the strain components.

Whether there is any difference between GAM, GOS and AMIS (I havn't heard this until now) can be only evaluated if the specific algorithm is published somewhere. It is similar to the band contrast, pattern or image quality. All numbers use different algorithms so that the resulting images look in maximum similar but never identical.

BTW: MTEX uses the term intragranular average misorientation angle per orientation for KAM which is the abbreviation for kernel average misorientation. There the accumulated misorientation angle of a field of 3x3, 5x5, 7x7 etc pixels around a respective measurement position is displayed. It describes the local misorientation gradient and enables to indicate locations of higher orientation differences probably caused by a higher density of geometrically necessary dislocations.           

A short addition: Whereas GAM and KAM give the local misorientation to a reference orientation (mean orientation of the grain or the misorientation within a kernel), GOS only characterizes the orientation spread with a korn as SINGLE number, i.e. GOS is a unique property of a grain, like the property "phase".

The grain orientation spread (GOS) is calculated by averaging the deviation between the orientation of each point in a given grain and the average orientation of that grain. While, grain average misorientation (GAM) is the average misorientation between all neighboring pairs of points in a grain. GAM is based on point-to-point misorientations inside a grain. Both of them are higher for strained structures. It seems that the average intragrain misorientation (AMIS) is the grain average misorientation (GAM)!

You can measure GAM using CHANNEL 5 but for obtaining GOS you should use other software such as OIM TSL or MTEX.

Hi Isadora you can see the chapter 18 of the book Backscatter Diffraction in Materials Science, in this book you can find some information about AMIS and GOS.

http://link.springer.com/book/10.1007%2F978-0-387-88136-2

Can Channel 5 be used to obtain GOS and GAP map?

Dear Isadora

I think the links below will benefit you in your search

http://engineering.snu.ac.kr/pdf%5C2005(22)%5C2005_CJH_Determination%20of%20a%20mean%20orientation%20in%20electron%20backscatter%20diffraction%20measurements.pdf

http://oro.open.ac.uk/37565/7/ORO_37565.pdf

Best Regards

hi,

so if i want to mesure misorientation in grain boundaries means between two adjacent grains,what can i use because local misorientation give misorientation between points in one grain and not between grains.

thanks in advance i hope i can find an answer.