Purpose
Testing the effectiveness of additives in oil or grease with respect to coefficient of friction, wear and fretting corrosion (tribocorrosion).
Brief description of the method
An upper test piece oscillates on a lower test piece, which usually has a round, lapped or polished surface. Approx. 2 to 3 drops of the test oil or grease are spread between these two test pieces. The following parameters can be changed:
On the apparatus
temperature
contact pressure
amplitude
frequency
test duration
On the test piece side
different materials
line contact (horizontal cylinders)
point contact (sphere)
area contact (ring)
other freely selectable geometries
A recorder plots a coefficient of friction diagram of the friction parameters throughout the test. In addition to this coefficient of friction diagram, visual assessment of the lubricant and optical and mechanical measurement of the friction points are also carried out. The optical measurement is made with the help of a microscope and the mechanical measurement with a surface measuring instrument (perthometer).
With the help of these data (coefficient of friction profile, depth of wear, diameter of wear, appearance of friction points and of lubricant), the lubricant can be assessed relatively quickly.
| DIN | ASTM | IP | Others |
|---|---|---|---|
| 51834 | D-5706 | - | ISO 12156-1 |
| D-5707 |