Tooth interior fatigue fracture

Tooth interior fatigue fracture, (TIFF), is a type of gear failure. The failure is characterised by a fracture at approximately mid-height on the tooth of the gear. This distinguishes it from a tooth root fatigue failure. The crack for a TIFF is initiated in the interior of the tooth. This distinguishes TIFF from other fatigue failures of gears. TIFF has been observed in case-hardened idlers (i.e. gear wheels loaded on both flanks during each revolution). Tooth interior fatigue fracture, (TIFF), is a type of gear failure. The failure is characterised by a fracture at approximately mid-height on the tooth of the gear. This distinguishes it from a tooth root fatigue failure. The crack for a TIFF is initiated in the interior of the tooth. This distinguishes TIFF from other fatigue failures of gears. TIFF has been observed in case-hardened idlers (i.e. gear wheels loaded on both flanks during each revolution).