Speaker
Description
Hydrogen-free amorphous carbon films gain increasing importance as wear resistant protective coatings in high-wear applications and are in industrial use on cutting tools and sliding components, especially in the automotive industry. Despite the broad use of these coatings in many applications due to their extremely high hardness, they reach their limits in applications with locally very high stress concentration.
Tailoring the (mechanical) properties often is an effective means for maximum performance in specific applications. Doping amorphous carbon coatings was found to be a promising approach to alter coating properties like hardness, residual stress, tribological interactions, surface energy, electrical resistance and others. The deposition of doped carbon coatings is easily realized with the LaserArc technique, because of its flexibility in the arc evaporation of manifold materials.
This presentation focuses on the effect of doping tetrahedral amorphous carbon coatings (ta C:X) deposited by LaserArc on the mechanical properties, especially fracture tolerance, for which an extensive investigation is given for the first time. For this purpose, ta C:X coatings doped with Boron, Molybdenum, Silicon, Copper and Iron were produced. The coatings were characterized by scratch testing, indentation fracture testing, high deformation bending on cylindrical mandrel and Raman spectroscopy.
The test evaluation was focused on the investigation of failure characteristics, especially crack appearance and the development of specific parameters for assessing the crack tolerance. Cross sections prepared by focused ion beam milling were utilized to investigate the indentation-induced cracks beneath the surface.
| Speaker Country | Germany |
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