Study On Application In Coating/film And Tribology Property Of Carbon Material

In this paper, AlSi composite coatings with different dimensions carbonnanomaterial additives were prepared on magnesium alloy matrix by plasmathermal spraying technique. The effects of different carbon nanoparticlescomposite coating additives on tribological properties under dry friction and oillubrication conditions has been investigated. In addition, we prepared a diamondfilm on silicon carbide ceramic substrate by microwave plasma chemical vapordeposition, and study on the tribological properties under different frictionconditions. The main contents of this paper are summarized as follows:1. The tribological behavior of Al-Si composite coating with differentcarbon reinforcement. Al-Si composite coatings reinforced with different carbonadditives were synthesized on Mg substrate surface, and the effect of the carbonadditives on the tribological behavior has been investigated under dry frictionconditions. The results show that the wear resistance of AlSi coatings wassignificantly influenced by their antifriction performance and relative hardness.The wear mechanisms of AlSi composite coating with additives were different.Al-Si coating reinforced with carbon nanotube exhibited most significantlyimproved tribological properties and a60%improvement in the wear resistance.Little furrows can be found on AlSi-0.5CNT composite coating friction surfaces, and adhesive material on the surface of the ball was the least.2. Tribological properties of AlSi composite coating carbon-reinforcedunder oil lubrication conditions. Under oil lubrication conditions, friction andwear properties of AlSi composite coating with the different dimensions carbonreinforcement have been tested. The result shows that the specimen maintainedat a good lubrication condition by use of one-time trace oil manner. Relative topure AlSi alloy coating, the surface wear resistance of carbon nanoparticlesreinforced composite coating have been improved. AlSi-0.5CNT compositecoating has a lowest friction coefficient of only0.12. Because of the nanoscalecarbon nanotubes can be used as lubricant additives in oil, it can formed alubricating film with excellent performance of lubrication on the frictioninterface, developed the tribological properties.3. Tribological properties of diamond thin films on silicon carbide ceramicmatrix. The diamond film has prepared on silicon carbide ceramic substrate bymicrowave plasma chemical vapor deposition, and the tribological properties ofdiamond films has been studied under dry friction and water lubricationconditions.The results show that the surface roughness and friction pairsmaterial have a very significant influence on tribological behavior of diamondfilms.Under dry friction conditions, the stabilization phase average frictioncoefficient of silicon carbide substrate and diamond film was0.2/0.18/0.45,0.47/0.66/0.5.This data shows that the MPCVD diamond films on silicon carbide substrate can effectively reduce the friction coefficient. Under waterlubricated conditions, the stabilization phase average friction coefficientdiamond film was0.13/0.18/0.27. Beacuse of the contact angle of water anddiamond films up to80°, the boundary lubricating layer will be formedbetween water and the diamond film contact surface, which has a very goodlubricating effect.