Friction and wear of SiC fiber-reinforced borosilicate glass mated to steel

Tribological performance of a SiC fiber-reinforced borosilicate glass was s tudied in unlubricated contact with a hardened and tempered hot-work tool s teel. Static and kinetic friction as well as wear in oscillating sliding co ntact were measured as functions of fiber orientation, relative humidity (r .H.) and testing temperature up to 500 degrees C in tribometers using ring- on-block geometry. The results showed that tribological properties were det ermined by fracture and tribochemically controlled processes depending on c ontact pressure, fiber orientation, humidity and temperature. Parallel (P) fiber orientation resulted in about equal static friction coefficient, but lower kinetic friction coefficient compared with transverse (TR) fiber orie ntation. Kinetic friction and amount of linear wear were reduced with incre asing humidity. While static friction increased continuously with temperatu re, kinetic friction increased between 25 and 100 degrees C strongly, but t hen the high value of the friction coefficient was constant up to 500 degre es C. Maximum amount of wear was measured at 300 degrees C. (C) 1999 Publis hed by Elsevier Science S.A. All rights reserved.