Combination of laser surface texturing and carbon coatings

Friction and wear play an important role in various technological applications. In particular, the possibility to tune tribological properties on the component level is very decisive. Nowadays, most machine elements are lubricated by oils or greases in order to separate the sliding surfaces partially or even completely and therefore to increase the number of life cycles. Despite the well-established performance of liqid lubricants such as oils, many applications operate under higher temperatures or even vacuum and thus oils and greases cannot be used. Apart from the usage of lubricants, laser- based techniques are promising candidates to tailor materials surfaces. Laser-patterned surfaces provide long-range ordered and well-defined surface topographies with cavities of variating depths in which for example wear particles can be stored thus reducing abrasive wear. However, it is known that due to the increased contact pressure, the resulting laser patterns will be worn quite quickly. In contrast to that, solid lubricants such as graphite or molybdenum disulfide may help to circumvent the abovementioned drawbacks by providing lubricity even under higher temperatures and vacuum conditions. But, the lubricant supply is not as easy as for an oil or a grease and so the solid lubricant will be removed as well with ongoing sliding time. In this context, a smart combination of the aforementioned methods would be exactly the way to tackle those issues. Combining laser- patterning with an advanced new solid lubricant based upon carbon nanoparticles, the resulting laser-patterns will be protected by the coating and additionally the carbon nanoparticles can be stored within the topographic lubricant pockets thus enhancing the lifetime of the overall system. High-resolution analytical and structural methods will be applied to study the materials surfaces and interfaces and moreover to elucidate the interaction mechanisms between the respective surfaces and the carbon nanoparticle coatings.

Friction and wear play an important role in various technological applications. In particular, the possibility to tune tribological properties on the component level is very decisive. Nowadays, most machine elements are lubricated by oils or greases in order to separate the sliding surfaces partially or even completely and therefore to increase the number of life cycles. Despite the well-established performance of liqid lubricants such as oils, many applications operate under higher temperatures or even vacuum and thus oils and greases cannot be used. Apart from the usage of lubricants, laser-based techniques are promising candidates to tailor materials surfaces. Laser-patterned surfaces provide long-range ordered and well-defined surface topographies with cavities of variating depths in which for example wear particles can be stored thus reducing abrasive wear. However, it is known that due to the increased contact pressure, the resulting laser patterns will be worn quite quickly. In contrast to that, solid lubricants such as graphite or molybdenum disulfide may help to circumvent the abovementioned drawbacks by providing lubricity even under higher temperatures and vacuum conditions. But, the lubricant supply is not as easy as for an oil or a grease and so the solid lubricant will be removed as well with ongoing sliding time. In this context, a smart combination of the aforementioned methods would be exactly the way to tackle those issues. Combining laser-patterning with an advanced new solid lubricant based upon carbon nanoparticles, the resulting laser-patterns will be protected by the coating and additionally the carbon nanoparticles can be stored within the topographic lubricant "pockets" thus enhancing the lifetime of the overall system. High-resolution analytical and structural methods will be applied to study the materials surfaces and interfaces and moreover to elucidate the interaction mechanisms between the respective surfaces and the carbon nanoparticle coatings.