Effect of laser heating on nanoscale wear of DLC thin films in an air environment

  • Norio Tagawa
  • Hiroshi Tani
  • Shinji Koganezawa
  • Renguo Lu
Technical Paper


In this study, fundamental experiments were conducted to understand the wear and related degradation characteristics of an ultra-thin DLC overcoat subjected to laser heating in an air environment, using a pin-on-disk tester. The experiments were conducted using DLC-coated glass pins and actual magnetic disks without a lubricant film. The differences in the wear and degradation characteristics of a DLC overcoat on the pin and disk surfaces, both with and without laser heating, were investigated after wear tests were performed, primarily through Raman spectroscopy. We found that the wear on DLC films became greater with laser heating, while the friction coefficients between the pin and magnetic disk became markedly smaller. This is because the wear observed in this experiment was predominantly due to a wear mechanism that is based on tribo-chemical oxidation.



This work was supported in part by Kansai University Grant-in-Aid for the Promotion and Upgrading of Education and Research 2016, and MEXT KAKENHI Grant Number 15H02216.


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© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department of Mechanical EngineeringKansai UniversitySuitaJapan

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