| Symbol | e*R |
|---|---|
| Unit | Nm/mm³ |
| Attribute-ID | apparent_friction_energy_density |
| Numeric ID | 200020 |
| Value Type | PMTechValue |
The apparent friction energy density relates the friction work WR performed on the tribological system to the wear volume VV. The apparent friction energy density thus represents a wear-specific friction work.
For a cylindrical gear (mn = 2 mm, z1/2 = 30/30), the following values were determined by optical measurement of the worn gears for dry running in FVA research project 856 I “Design of injection-molded plastic gears” (www.themis-wissen.de/#/portal/project/228269/Auslegung-spritzgegossener-Kunststoffzahnr-der ([in German]) for the material pairing 16MnCr5/PA46-GF30:
| Output torque | Apparent friction energy density |
| 10 Nm | 14500 Nm/mm3 |
| 20 Nm | 21200 Nm/mm3 |