18-10-2021, 10:09 PM
Although it is difficult to see clearly from the pics, they both look like fatigue cracks, the initiation point can be any defect or notch that causes a local discontinuity in a highly stressed area. The crack growth is, I believe, indicated by the grey areas surrounding the central break. Fatigue cracks will grow until there is insufficient sound material remaining and then failure occurs.
Brittle failure if my memory serves me correct is more crystalline in appearance.
Fatigue life was always defined as 90% initiation and 10% propagation, so once the crack is initiated life of the component is virtually over.
Brittle failure if my memory serves me correct is more crystalline in appearance.
Fatigue life was always defined as 90% initiation and 10% propagation, so once the crack is initiated life of the component is virtually over.