In situ Raman spectroscopy of annealed diamondlike carbon-metal composite films

Diamondlike carbon films and diamondlike carbon-metal composite films may provide increased component reliability, decreased fuel consumption, decreased noise/vibration/harshness (NVH), and decreased lubricant use in next generation automotive components. Raman spectra were obtained for diamondlike carbon, diamondlike carbon-platinum composite films, and diamondlike carbon-gold composite films, which were annealed to a temperature of 523 °C. The Raman spectra for these films were fitted using a two-Gaussian function. The variation of the G-peak position, the D-peak position, and the ID/IG ratio was examined as a function of temperature. The unalloyed diamondlike carbon film demonstrated greater thermal stability than the diamondlike carbon-noble metal composite films. These results suggest that the operating temperatures of the diamondlike carbon-coated automotive components must be kept under careful consideration.