|
CLASS |
General mode |
Specific mode or degree
|
Not preferred |
|
Wear |
Adhesion
Abrasion
Polishing
Corrosion
Fretting corrosion
Scaling
Cavitation
Erosion
Electrical Discharge
Rippling
|
Mild
Moderate
Severe (see scuffing)
Mild, Moderate, Severe
Mild, Moderate, Severe |
Running-in-wear
Scoring
Scratching
Cutting
Burnishing |
|
Scuffing |
Scuffing
|
Mild, Moderate, Severe |
Scoring
Cold scuffing
Hot scuffing
Welding
Galling
Seizing
|
|
Plastic deformation |
Plastic deformation
|
Indentation
Cold flow
Hot flow
Rolling
Tooth hammer
Rippling
Ridging
Burr
Root fillet yielding
Tip-to-root-interference
|
Bruising
Peening
Denting
Brinelling
Permanent deformation
Overheating
Fish scaling
|
|
Contact fatigue |
Pitting (Macropitting)
Micropitting
Subcase fatigue
|
Initial
Progressive
Flake
Spall |
Destructive
Arrow head
Frosting
Gray Staining
Peeling
Case crushing
|
|
Cracking |
Hardening cracks
Grinding cracks
Rim and web cracks
Case/core separation
Fatigue cracks
|
|
Quenching cracks
Internal rupture
|
|
Fracture |
Brittle fracture
Ductile fracture
Mixed mode fracture
Tooth shear
Fracture after plastic deformation
|
|
Fast fracture
Smearing
Semi-brittle
|
|
Bending fatigue |
Low-cycle fatigue
High-cycle fatigue |
Root fillet cracks
Profile cracks
Tooth end cracks
|
|
