THERMAL STABILITY STUDY OF DIAMOND-LIKE CARBON FILMS CONTAINING CRYSTALLINE DIAMOND NANOPARTICLES

Beatriz Campos Ramos,Fernanda Roberta Marciano,Vladimir Jesus Trava-Airoldi,Anderson Oliveira Lobo,Marina Fernandes Stein

doi:10.18066/revunivap.v20i35.164

Beatriz Campos Ramos, Fernanda Roberta Marciano + Show 3 more

Open Access

https://doi.org/10.18066/revunivap.v20i35.164

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Journal: Revista UniVap	Publication Date: Aug 22, 2014
License type: cc-by

Affiliation: Universidade do Vale do Paraíba

Abstract

Nanocrystalline diamond (NCD) particles are incorporated into diamond-like carbon (DLC) films in order to prevent NCD-DLC electrochemical corrosion. In the current paper, the thermal stability of these films was investigated. The NCD-DLC films were deposited on 316L stainless steel substrates using plasma enhanced chemical vapor deposition. The grain size of the diamond crystallites and their concentration were varied in order to obtain different NCD-DLC films. The samples were annealed to 50°C for 1 h. The annealing temperature increased until the complete graphitization of the films (ramp of 50°C). Raman scattering spectroscopy was used to evaluate in detail the chemical structure of the DLC and NCD-DLC films. The atomic arrangements and graphitization level according to the increasing temperature are discussed. The influence of NCD particle sizes and concentration on NCD-DLC thermal stability are also discussed. The results showed that the presence of crystalline diamond particles increased the graphitization temperature, which permits the use of NCD-DLC films in high temperature environments.

Highlights

Diamond-like carbon (DLC) coatings have been actively studied over the last decade in the field of material engineering
The investigation of thermal stability of DLC films deposited using plasma enhanced chemical vapor deposition (PECVD) technique showed changes in mechanical and tribological properties at temperatures greater than 200°C, resulting from sp3 to sp2 transformation accompanied with hydrogen effusion (LI et al, 2006)
Raman scattering spectroscopy is popularly used to probe the quality of DLC films due to its ability to distinguish between different bonding types and domain sizes (FERRARI; ROBERTSON, 2000; TAMOR; VASSEL, 1994)

Summary

INTRODUCTION

Diamond-like carbon (DLC) coatings have been actively studied over the last decade in the field of material engineering. The thermal degradation of DLC films is a major problem in achieving high temperature applications due to the conversions of sp to sp hybrid orbitals which forms the C-C bonds and the loss of diamond-like properties (CHOI et al, 2007). The investigation of thermal stability of DLC films deposited using plasma enhanced chemical vapor deposition (PECVD) technique showed changes in mechanical and tribological properties at temperatures greater than 200°C, resulting from sp to sp transformation accompanied with hydrogen effusion (LI et al, 2006). In our previous manuscript (MARCIANO et al, 2010a), it was show for the first time the use of DLC films with nanocrystalline diamond (NCD) particles incorporated in their structure. Raman scattering spectroscopy was used to investigate the thermal stability of NCD-DLC films at different concentration

EXPERIMENTAL PROCEDURES

RESULTS AND DISCUSSION

CONCLUSION