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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.
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What is Failure? How is it defined?
Familiar Failure • Conventional tensile failure mode that we are all familiar with.
You would not be worrying about this failure at the time it occurred!
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!