08:49 Sep-17-2004 S.V.Swamy Engineering, - Material Testing Inspection & Quality Control Retired from Nuclear Fuel Complex , India, Joined Feb 2001 784
Re: MPI-crack detction ----------- Start Original Message ----------- : While testing a component after Heat Treatment a surface crack indiction is seen.how to judge wheater the crack has taken before : Ht or after HT. ------------ End Original Message ------------ One way would be to look within the crack for evidence of oxidation/scaling. If the crack was existing prior to heat-treatment, the crack faces would have been exposed to the furnace atmosphere and would show some scaling. If the crack was extremely tight and got opended up or if the crack was produced by stress relieving, the crack surfaces would be relatively clean and fresh.