There are two grades of Highly oriented pyrolytic graphite, its HOPG-A and HOPG-B.
HOPG-B, is a Pyrolytic Graphite Crystal, flat, mosaic spread 0.8+/- 0.2 deg. Max Size: 50 x 50 mm, Thickness: 4-5 mm. We have stocks for this size.
Testing of the HOPG-B:
HOPG-B-50-50-4mm
We have make a testing for samples. see bellow details:
Instrumentation: German Brook X-ray diffractometer.
Power: 20Kvx5ma, slit: Ds0.05, Ss1.0mm, Rs0.2mm.
First measure 2 Hita, from 24 degrees to 28 degrees, and measure the peak value of 2 Hita at 26 degrees as the peak position! Then single-action Hita, scan the crystal from 11 degrees to 16 degrees, get the half-width of the line of Hita, and measure the data of the full width at half maximum, which is the value of the mosaic angle of the product. The middle, left and right points can be measured separately to verify the uniformity of the crystal facet. The above is our normal test method for customer reference.
The angles are: 0.841 degrees on the left side (10 mm from the side): 0.886 degrees in the middle: 0.861 degrees on the right side (10 mm from the side). After 90 degrees of rotation, the left side (10mm from the side) is 0.946 degrees: the right side (10mm from the side) is 0.707 degrees.
You can check the properties of the HOPG below:
HOPG data sheet