Issue 32/2015 - Controllable preparation of high vacuum carbon-based films

The Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences has recently made new breakthroughs in the failure nature and life extension of fluorinated amorphous carbon-based films in high vacuum environment, and successfully realized the ultra-long wear life design and controllable preparation
of fluorinated amorphous carbon-based films under high vacuum conditions.

At present, China's space machinery and equipment put forward more demanding performance requirements
for motion mechanisms than ever before, such as high precision, high reliability and long life.
Due to its excellent tribological properties in high vacuum environments, fluorinated amorphous carbon-based films are ideal for solid lubricating film materials
in high vacuum environments.
However, fluorinated amorphous carbon-based films usually manifest as instantaneous sudden wear failure during friction under high vacuum conditions, and so far, the essential mechanism of this wear failure is still unclear, and its wear life can not meet the demanding requirements
of high reliability and long life.

The research group confirmed for the first time that the strong adhesion between the contact interfaces caused by graphitization caused by shaping under high vacuum conditions directly led to the essential failure of the film, and designed a friction model test of fluorinated amorphous carbon-based film under vacuum, which verified that the essential failure mechanism of the film in high vacuum is the strong adhesion
between the interfaces caused by graphitization.

On this basis, researchers have successfully realized the ultra-long wear life design and controllable preparation
of fluorinated amorphous carbon-based films under high vacuum conditions.
Through composition design and multi-layer interface microstructure construction, researchers successfully designed and prepared fluorinated amorphous carbon-based films with low internal stress, and generated thermodynamic and structurally stable FeF2 nanocrystalline friction films in situ through friction interfaces, avoiding strong adhesion
between friction interfaces.
The amorphous carbon-based film exhibits excellent tribological properties such as low friction and ultra-low wear under high vacuum, which lays a solid theoretical and material system foundation
for further expanding the application of carbon-based films in the field of space technology.

(Chemical)