We have had some issues with scratches in a black oxide surface on a steel part. During investigation we discovered a very strange phenomenon at the bottom of some of the scratches. See attached picture. It's a pattern of perfect rows of dots/holes with a spacing of approximately 8 microns in both axes. One pattern is 15x15 dorts and the other 13x9. According to the laboratory these may be imprints from some kind of tooling or measuring equipment. This may be the wrong forum for this question, but maybe someone has seen something similar.
Thanks in advance!
Thanks in advance!
