Failure and Fully Plastic Action

This week we'll look at the definition of failure, failure theories, and real-life examples of failed components.  You will yield a piece of steel in flexure and refer back to your previous tests in order to compare the tensile, torsion, bending and direct-shear yield points of this material.  We'll compare these experimental results to the maximum shear stress, maximum octahedral shear stress, maximum principal strain, and maximum principal stress theories.....and estimate which theory works best for this material.  Finally, we will investigate failed components, estimate what caused the failure, and propose a remedy.

Video Lecture (26 minutes) Notes Objectives Failure Analysis ide20 lesson by Dr. R. Hutcheson asm handbooks see Volume 11 procedure by Dr. J. Purbolaksono risk in early design by Dr. K. Grantham intro (13 MB) example: using the red software (21 MB) Failure Examples general news s&t examples Failure Theories video notes Fractography asm handbooks see Volume 12  and Volume 11: Principles and Practice of Failure Analysis, Examination of Damage and Material Evaluation, Interpretation of Damage and Fracture Features failure in bending cleavage and fracture Fully-Plastic Action short version full version Assignment

photos by Jeff Thomas, 2002

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