Page 351 - Failure Analysis Case Studies II
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                             Fig. 4. Enlarged view of a cracked oxide scale located in thinned area.






                                                oxide scale

                                                                  oxidation pit














                                                                  J



                                                                         by grinding




                                                 \
                                         tube metal crack under oxide scale
                       Fig. 5. Preparation of metallographic sample for studying crack initiation mechanism.
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