I have very small Ti specimens, and I want to use epoxy mounting directly in the chamber of XRD, but I am afraid that this addition of material will affect the output XRD peaks. May I first perform a dummy test with the epoxy mounting only, to check its peaks? What about plastics and double face tape as holders?
You may either perform a test scan on epoxy before mounting or you may mount it in an amorphous polymer. It depends upon the type of information that you want to obtain from the XRD scan.
As others have said, it depends upon the epoxy and what information you wish to derive. I would suggest running some test scans before deciding upon a method.
So long as you select a non-filled simple epoxy which is amorphous in nature you may be ok. You can also try a custom amorphous plastic or aluminium sample holder.
Alternatively, dare I say, Blu-tack or a similar amorphous putty (Apiezon Compound Q for example) may help keep your samples stationary on another flat stage (but at all times you must ensure that the sample height and angle of measurement is not effected)
I've recently scanned Loctite 5 minute Epoxy and found it to be amorphous with only two VERY small peaks. In the attached image, the high count rate at low angle is due to the large divergence slit used. I've tried a number plastics and most have a substantial crystalline fraction. I have not tried "scotch" clear sticky tape, but black electrical tape had a lot of strong peaks. The classic way to hold small samples that only fill a small portion of the beam is Vaseline (petroleum jelly) and a "zero background" plate. The "zero background" plate is a single crystal of quartz or Si cut off-axis so there will be no peaks at all in the theta/2-theta configuration. A thin layer of grease like Vaseline will hold a small specimen on the "zero background" holder.
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