|
Table 7.1: Failure mode classification for gears (ISO 10825). |
1. Indications of
surface
disturbances |
1.1 Sliding wear |
1.1.1 Normal wear
(Running in wear)
1.1.1.1 Moderate wear
1.1.1.2 Polishing |
|
|
1.1.2
Abrasive wear |
|
|
1.1.3
Excessive wear |
|
|
1.1.4
Moderate scratching
(Scoring) |
|
|
1.1.5
Severe scratching |
|
|
1.1.6
Interference wear |
|
1.2
Corrosion |
1.2.1
Chemical corrosion |
|
|
1.2.2
Fretting corrosion |
|
|
1.2.3
Scaling |
|
1.3
Overheating |
|
|
1.4
Erosion |
1.4.1
Cavitation erosion |
|
|
1.4.2
Hydraulic erosion |
|
1.5
Electric erosion |
|
| 2.
Scuffing |
|
|
3.
Permanent
deformations |
3.1
Indentation |
|
|
3.2
Plastic deformation |
3.2.1
Plastic deformation
by rolling |
|
|
3.2.2
Plastic deformation
by tooth hammer |
|
3.3
Rippling |
|
|
3.4
Ridging |
|
|
3.5
Burrs |
|
4.
Surface fatigue
phenomena |
4.1
Pitting |
4.1.1
Initial pitting |
|
|
4.1.2
Progressive pitting |
|
|
4.1.3
Micro pitting |
|
4.2
Flake pitting |
|
|
4.3
Spalling |
|
|
4.4
Case crushing |
|
| 5.
Fissures and cracks |
5.1
Hardening cracks
(Quench cracks) |
|
|
5.2
Grinding cracks |
|
|
5.3
Fatigue cracks |
|
| 6.
Tooth breakage |
6.1
Overload breakage |
6.1.1
Brittle fracture |
|
|
6.1.2
Ductile fracture |
|
|
6.1.3
Semi-brittle fracture |
|
6.2
Tooth shear |
|
|
6.3
Breakage after
plastic deformation
(Smeared fracture) |
|
|
6.4
Fatigue breakage |
6.4.1
Bending fatigue |
|
|
6.4.2
Tooth breakage |
iso
fAILURE mode classification for gears (ISO 10825)
Failure
modes of various machine elements are presented in chapter 7