Adhesion reducing of elastomers with plasmapolymeric coating

Elastomers are of particular interest to a variety of industrial products such as O-rings and other seals, due to their characteristic properties, e.g. rubber elasticity or chemical resistance. A disadvantage of this material is the relatively high coefficient of friction and thereof the result wear. To improve the friction and wear behavior of the elastomer, a plasmapolimeric coating is applied on the surface. The coating is deposied by plasma enhanced chemical vapor deposition (PECVD). In essence, the friction behavior of elastomers is characterized by two mechanisms- by adhesion and hysterisis. Using a tribological test rig and with varying test temperasture and velocity, friction curves are created. The tests were performed with Pin-on-plare contact geometry, lubricated using axle gear oil based on PAO and also with Ball-on-disc contact geometry without lubrication. Typical for friction curves of elastomers are the adhesion peak at lower velocities and the hysterisis peak at higher velocities (1). By comparing the curves of uncoated and plasmapolymeric coated FKM, the influece of the plasmapolymeric coating on the adhesion and hysterisis of the FKM can be investigated.