Nice to hear from you again, Mr. Mark. I will now try to answer your specific question about scratch depth and later then respond to the rest of your post.
Mr. Mark, you are correct that there is no need why a scratch should be 8x as wide as it is deep. The graph was used to demonstrate that the scratch depth can be estimated when we measure the scratch width on the surface and to show that the scratch depth is often significantly smaller than scratch width.
Optical scratch testers are modern instruments for imaging scratched surfaces and for measuring of surface mechanical properties. Normal scratching includes deformation such as ploughing, but might also involve material cracking and removal.
See the attachment. (https://www.rtec-instruments.com/indenta...tester.htm)
Jan
Mr. Mark, you are correct that there is no need why a scratch should be 8x as wide as it is deep. The graph was used to demonstrate that the scratch depth can be estimated when we measure the scratch width on the surface and to show that the scratch depth is often significantly smaller than scratch width.
Optical scratch testers are modern instruments for imaging scratched surfaces and for measuring of surface mechanical properties. Normal scratching includes deformation such as ploughing, but might also involve material cracking and removal.
See the attachment. (https://www.rtec-instruments.com/indenta...tester.htm)
Jan