Uncovering Diamond-like Carbon Films Super Lubricity: From Microscopic to Macroscopic

Diamond-like carbon (DLC) films achieved superlubricity rapidly, making them a promising material for the development of mechanics and manufacturing. However, the fundamental mechanisms governing friction evolution at the interfaces remain elusive. This study utilized atomic force microscopy to investigate the friction behavior of nanoscale interfaces formed by DLC films under macroscopic friction experiments. The evolution of sp2-hybridized carbon structures on different load transfer film interfaces was observed. Finally, combining Raman spectroscopy demonstrated that the formation of rich sp2-hybridized carbon structure transfer films is a primary factor in reducing the nanoscale friction of DLC films. This research fills the gap in the structural evolution of DLC films at friction interfaces and reveals the nanoscale mechanism behind the macroscale friction phenomenon of DLC films.