Evaluation of elastoplastic properties and fracture strength of thick diamond like carbon film by indentation

The elastoplastic properties and fracture strength of thick diamond like carbon films (with thickness over 10 µm) are studied. An indentation-based framework is outlined where the dual sharp shallow micro indentation method is employed to measure the elastoplastic properties of the film and the substrate; next, integrated acoustic emission and corrosion potential fluctuation techniques are employed to characterize the ring cracks formed due to deep spherical indentation. The fracture strength of the DLC film is obtained from parallel numerical simulations with the identified elastoplastic properties. It is found that the thick DLC film prepared by using the plasma-based ion implantation method has better fracture property than thin DLC films in previous studies.