Abstract
Thermally refined steel rollers are fatigue tested under three sliding-rolling contact conditions while varying the specific sliding during the rotation of a test roller by using a newly produced variable specific sliding type contact roller testing machine. With this method, the surface durability under each condition is elucidated. The test results obtained here are compared with the results obtained by a conventional rolling contact fatigue test with constant specific sliding. The relationships between the characteristics, such as frictional torque under each variable specific-sliding condition, and the surface roughness and pitting distribution on the test roller are discussed. The surface durabilities under variable specific-sliding conditions are lower than those under a constant specific-sliding condition. The roller surface roughness tends to be lower at a position of higher absolute value of specific sliding, and the amount of pitting tends to be greater at a position of higher absolute value of frictional torque.