Hello GRoberts, I hope this doesn't sound too simplistic. Is the material that you are looking to determine this on already sheared or otherwise cut from the master plates or sheets? If you have material that is 1/2" or under that is in a sheet form generally 2 of the edges will have a somewhat rounded edge as a result of the rolling process and the other 2 edges will likely have been sheared as much of this material is uncoiled and straightened and then sheared to length. In this case the grain would run parallel to the rounded edges of the material. If this material is from heavy plate sections and they are in their full sizes generally the grain will run parallel to the longest side of the plate, but not always, or as is the case with the other 1/2" and under material that I described, the grain will run parallel to the two edges that have a more rounded and mill scaled appearance.
In another scenario here I will make the assumption that you have parts that have already been sheared or cut and you are in need of determining grain for the sake of preventing fractures associated with forming processes. In that case I am at a loss for determining grain without going to some form of destructive process or the metallography that you referred to. Can you give any more details for the need to know grain direction? Please forgive me if you are already aware of the above information. Regards, aevald
Unfortunately, the 1" plate is already flame cut on all edges. It is a drop, and I need to make sure the weld tests cut from it have the grain going the right way.
I may be ignorant, but in your situation I can't think of any other way to determine roll direction other than getting a close look at the grain structure.
Sounds like you are testing bends. If you have extra material from the cut piece take a sample that is about the same length and width of the bend sample. (Assume a direction and make sure you remember it) Round the edges and grind and polish an area in the middle of the sample on both front and back. This will simulate the weld. Bend the sample on a radius slightly smaller that your actual test. If you chose the correct direction it should not break or begin to crack/split. If it is the wrong direction cracking should occur.
Seems very simple but it has worked for me on numerous occasions.
I very much agree with you M-Squared, the only issue he may have here in this case would be if his drop is cut in such an way that the grain might run at a 45 degree orientation to his scrap piece(assuming that the scrap was a square or rectangle). So it might be a bit of a crap shoot. My $.02, Regards, aevald
I don't know the materials manufacturing method off the top of my head, but I could find it out. It would be interesting to check with UT. I think I might try M-Squared's idea though. If the plate passes a more stringent bend test than required for my testing, I guess it doesn't really matter which way the grain direction is. I was thinking that putting a deliberate notch into the sample might make the test more sensetive? So many interesting things to try, but so little time.
Mr. Roberts,
Do you know anything about the plate material's manufacturing method? For instance, with TMCP plate you can usually determine rolling direction with ultrasonics (shear wave). You will note a distinct difference in the angle of sound transmission and in attenuation between the rolling direction and the transverse to rolling direction.
Mankenberg
THAT is very interesting. I don't have any experience with UT other that observing it being done, but I do know how difficult it can be to determine the rolling direction when all 4 sides of a plate have been cut.
I assume by your post that not every material type can be checked that way but that might prove useful sometime. Thanks for passing that on to us.
Well I hate to admit it, but nowadays my best guess work gets me close enough. I've done enough rolling offsets on pipe, that I can generally figure out what I've got by the time my leads are strung out. When I first started I fought and fought, and worked till broad daylight to get the rigs up and running again. It wasn't any fun, but I didn't learn what I know from a book. That's one thing my a.d.d. doesn't afford me. . . . .lol
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