failureofmaterials
DESCRIPTION
TRANSCRIPT
Failure of Materials in Service
What is Failure?
How is it defined?
Is this failure?
What about this?
Or this?
Familiar Failure
• Conventional tensile failure mode that we are all familiar with.
Brittle Fracture
Ductile Fracture
Failure in Compression
Failure in Torsion
Failure in Bending
Stiff stuff getting bent!
Failure in little bits!
Sneaky failure
Fatigue Failure
Quietly in the hidden places failure
You would not be worrying about this failure at the
time it occurred!
Will you ever fly in a plane again!
Bolting the door after the …..
Expensive can-opener!
A new slant on bird ingestion
Where did that runway go?
Brake failure or pilot error?
Pardon me sir!
This was frozen when I took off!
A watery grave
Why Failure?
All unanticipated mechanical failures must have a cause:
• Designed incorrectly• Manufactured incorrectly• Mis-maintained• Mis-operated
Typical modes of failure
• tensile, compressive & shear• bending (buckling)• distortion, residual loads.• creep (temperature / stress related)• thermal shock• corrosion (including stress corrosion)• ageing• wear, fretting• fatigue• And lastly, cracks in the fuselage!