DEVELOPMENT OF BALL-BEARINGS WITH SOLID FILM FOR HIGH-VACUUM, HIGH-TEMPERATURE, HIGH-SPEED APPLICATION

This paper describes the experimental results of long-life solid lubricated ball bearings tested under high-vacuum of 10(-4)Pa, high-temperature of 300-degrees-C and high-speed of 9000rpm conditions. For full ball-type bearings, the thin soft metals, either Ag or Pb, which were coated on the races and balls, appeared to have good torque properties. However, the durability of such bearings was less than 300 hours. The transfer films from the lamellar solid MoS2 and metal composite retainers improved the torque and wear properties. For ceramic, i.e., silicon nitride, balls used with steel rings, wear occurred on the inner rings. All ceramic bearings with composite retainers showed improved torque and wear properties.