In the quest for advanced materials that can withstand the harsh conditions of energy sector applications, researchers have made a significant stride. A recent study published in *Cailiao Baohu* (translated as *Materials Protection*) explores how varying methane flow rates during the production of diamond-like carbon (DLC) composite films can dramatically influence their structure and performance in low-vacuum environments. This research, led by WANG Zhanzhuo and LI Hongxuan from the State Key Laboratory of Solid Lubrication at the Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, could have profound implications for the energy sector, particularly in applications requiring durable, low-friction coatings.
The study focused on Ti/Si/O multi-element composite DLC films, prepared using magnetron sputtering at different methane flow rates. The findings revealed that as the methane flow rate increased, the films exhibited a nanolayered structure with alternating Ti/Si enrichment. This structural evolution had a direct impact on the mechanical properties of the films. “We observed a significant decrease in hardness and elastic modulus as the methane flow rate increased,” explained WANG Zhanzhuo. “This was primarily due to the formation of more polymeric sp3-CHn structures, which softened the material.”
The research also highlighted the importance of the modulation period of the nano multilayer structure. As the methane flow rate increased, this period decreased, enhancing the film’s toughness. This structural change led to a transition from brittle to ductile spallation, a critical factor in the film’s durability. “The reduction in the modulation period improved the film’s ability to withstand mechanical stress, making it more resilient in demanding applications,” added LI Hongxuan.
In low-vacuum conditions, the tribological performance of the films varied significantly with methane flow rates. Films deposited at lower flow rates (below 30 mL/min) exhibited poor performance, with rapid wear-through and failure. However, as the methane flow rate increased, the passivation effect of hydrogen at the friction interface weakened the interaction between friction pairs, leading to a decrease in the friction coefficient. At a methane flow rate of 30 mL/min, the films demonstrated optimal tribological performance, with the lowest friction coefficient and wear rate recorded.
This research is particularly relevant for the energy sector, where components often operate in low-vacuum environments and are subjected to high mechanical stress and wear. The ability to tailor the mechanical and tribological properties of DLC films through controlled methane flow rates opens up new possibilities for developing advanced coatings that can enhance the performance and longevity of energy sector components.
The findings suggest that by optimizing the methane flow rate during the deposition process, it is possible to produce DLC films with superior mechanical properties and tribological performance. This could lead to the development of more durable and efficient components for energy applications, ultimately reducing maintenance costs and improving overall system reliability.
As the energy sector continues to evolve, the demand for advanced materials that can withstand extreme conditions will only grow. This research provides valuable insights into the potential of DLC composite films and paves the way for future developments in the field. With further refinement and commercialization, these films could become a game-changer in the energy sector, driving innovation and efficiency.