Adhesion strength evaluation of diamond-like carbon coatings via acoustic emission and characterization of delamination modes using fast fourier transform analysis
Year: 2025
Type: article
Abstract: Diamond-like carbon (DLC) coatings exhibit high hardness and low friction coefficient, making them effective in reducing friction under lubricated conditions. As their application to engine components becomes more widespread, ensuring the reliability of these coatings has become increasingly important, with a particular emphasis to be paid on the management of their adhesion strength. So, this study aims to establish a method of evaluating the adhesion strength of DLC coatings by studying the acoustic emission (AE) signals generated by the releasing elastic energy of the coating delamination. Meanwhile, the critical contact pressure at which AE signals first appear during lubricated friction tests was identified as an indicator of the delamination onset. Additionally, AE-based analysis has been gaining attention for friction and wear evaluation, with approaches such as FFT analysis being employed to assess the corresponding failure conditions. Along these lines, we conducted friction tests using ta-C films with different delamination modes and analyzed the corresponding AE signal characteristics including event count, amplitude, frequency, and energy. The results clearly demonstrated that the AE signals varied significantly depending on the delamination mode. Furthermore, the findings indicate that analyzing these AE parameters is beneficial in understanding the progression of the DLC coating delamination.
Source: Tribology International
Authors: Rikuto Taguchi, Yutaka Mabuchi
Institution: Utsunomiya University
Language: English
Subfield: Mechanics of Materials
Field: Engineering
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $5,390
OpenAlex ID: W4416957608