I am trying to model the fatigue response of a wire-arc additive manufactured specimen of Ti64 alloy. It has large columnar grains with sizes greater than 3 mm. I was using cyclic plasticity, but now I want to introduce the effect of microstructure. Crystal plasticity is used in the literature for this purpose, but I cannot get an EBSD map of even 1 complete grain due to the large grain sizes.
Can anyone suggest some better options?
Are you trying to extrude your EBSD scan and convert it into an FE mesh to use in a crystal plasticity model or Are you trying to build synthetic microstructures based on the statistics you generate from the EBSD scans?
If you are trying to use a high resolution on your EBSD scans (like 0.25 or 0.5 microns/voxel) then it might take a long time to take the scan on your specimen. How about lowering the resolution (say 3 - 4 microns/voxel) and try to scan a larger area and then see if you are able to capture multiple grains in your specimen?
How about using DREAM.3D to create synthetic microstructures based on the data that you can gather from EBSD, and then use the synthetic microstructures in your study.
Those were just a couple of suggestions that I have.
Hope that helps.
Thank you for your answer. I mapped with a step size of 3microns, and that was still not enough to get one grain, as I could only map 1200 by 1200 microns in 3 days. The maximum area that I can map (even with a low resolution) is 1600 by 1600 microns in the EBSD. I was hoping to get the data from the EBSD scan and convert it into an FE mesh. I can see the grains only by macro-examination. Perhaps, I have to create a synthetic microstructure and randomly assign the grain orientation.
Just curious, do you plan to model different microstructure through thickness?
Hi, What is the fps that you get in your EBSD system.... I suppose all you want is to incorporate the orientation information to individual tessellae, for your FEM simulation. If you say, EBSD scan takes roughly 3 days, it implies that your fps is: (1600*1600)/(3*3)/ (3*24*3600) ~ 1.1 fps. Most SEM's can now aquire scans at ~ 30-100 fps. So, the time taken for you scans can be significantly reduced. Since, you are mostly interested for the orientation of the grains, you can perform a transverse scan (perpendicular to orientation of columnar grains) with a coarse scan say, 5 microns. Now, the time required would be, (3500*3500)/(5*5)/50fps ~2.72 hrs..even for 50 fps. So, I was just wondering what is the maximum scan rate, in fps possible in your EBSD set-up .
Thanks
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