WEAR LIFE OF SOLID FILM LUBRICANTS: D2981
EXPLANATION
This test method is used for determining the wear life properties of bonded solid film lubricants under oscillating motion by means of a block-on-ring friction and wear testing machine. This test method differentiates between bonded solid lubricants with respect to their wear life. If the test conditions are changed, relative wear life may change and relative ratings of the bonded solid film lubricants may be different.
TEST SUMMARY
The machine is operated using a coated steel testing ring oscillating against a steel test block. The oscillating speed is 87.5 cpm at a 90° arc. The specimens are worn-in for 1 min at 30 lb normal load. Wear-in is followed by application of a normal load of 630 lb for the duration of the test. One measurement is made. Wear life is defined as the number of cycles required for the frictional force to rise to a pre-determined value.
TEST PRECISION
Repeatability: 25 % of mean of wear life
Reproducibility: 33 %
Bias has not been determined.
