Sub-Microindentation Hardness Tests on Thin Film Magnetic Disks
Abstract
The Point Contact Microscope is used to conduct indentation hardness tests on thin film magnetic disks. Determinations of the indentation depth and area are critical to the measurement of hardness when the indentation depth is on the order of the surface roughness. An algorithm is developed to first locate the overlap part between the indented and original surfaces and then subtract the two to more precisely determine the indentation depth and area. This technique is used to determine the hardness of the nominally 20-40 nm thick carbon/zirconia protective overcoats of thin film disks. It is found that the zirconia overcoat is somewhat softer than the carbon overcoat, and the carbon overcoat is about 4 to 5 times harder than the magnetic layer.
- Publication:
-
Advances in Information Storage Systems
- Pub Date:
- 1995
- DOI:
- 10.1142/9789812831415_0011
- Bibcode:
- 1995adss.book..163L