| 1. |
- Mallipeddi, Dinesh, 1987, et al.
(författare)
-
Effect of Running-In (Load and Speed) on Surface Characteristics of Honed Gears
- 2019
-
Ingår i: Tribology Transactions. - : Informa UK Limited. - 1040-2004 .- 1547-397X. ; 62:3, s. 412-418
-
Tidskriftsartikel (refereegranskat)abstract
- The initial running-in cycles alter the surface integrity characteristics and influence gear performance. This article shows how the surface characteristics of honed spur gears evolved due to the combined effect of running-in load (0.9 or 1.7 GPa) and speed (0.5 or 8.3 m/s) in Forschungsstelle fur Zahnräder und Getriebebau tests. Running-in affected the surface layers to a depth of 5 µm. High running-in load promoted plastic deformation of asperities, created microstructural changes associated with surface cracks, and relaxed residual stresses. It also enhanced the amount of phosphorous from extreme pressure (EP) additives at the surface. The surface contact fatigue failure—that is, micropitting—was promoted by running-in speed rather than load.
|
|
| 2. |
- Mallipeddi, Dinesh, 1987, et al.
(författare)
-
The effect of manufacturing method and running-in load on the surface integrity of efficiency tested ground, honed and superfinished gears
- 2019
-
Ingår i: Tribology International. - : Elsevier BV. - 0301-679X .- 1879-2464. ; 131, s. 277-287
-
Tidskriftsartikel (refereegranskat)abstract
- This study compares gear surface characteristics generated by grinding, honing and superfinishing of case-hardened steel, including the evolution during efficiency testing with two different prior running-in loads (0.9 GPa and 1.7 GPa). The most influential factor was surface roughness. Micro-pitting was associated with surface asperities and hence only seen in ground and honed gears, while being absent for super-finished gears. The micro-pitting was enhanced by running-in load, but only for rough surfaces. Deformation-induced localized microstructure impact was associated with cracks. Residual stresses reached similar levels after efficiency testing. Phosphorous content in the gear surface was connected to surface roughness and running-in load.
|
|
