|
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 |
|