| Abstract |
| Since the aircraft accidents caused by fatigue failure far less the service life estimated in 1950`s, damage tolerance design concept assuming pre-crack existence on the aircraft structures was introduced, and crack growth measurement was requested to correlate theoretical fatigue crack growth rate by modifying the theoretical analysis parameters. In this study, 3 specimens from 3 different structure tests (coupon test, component test and full scale test) were selected and examined to verify fatigue crack growth rate. Before starting metallographical observation to each fracture surface, each test spectrum was truncated to select high load points and SEM observation was done to match well developed striations on the fracture surface to the selected load points. Also characteristic analysis technique effective to each structure test was suggested and confirmed through this study. With the crack growth data obtained by fractographic analysis, it is possible to give the information to correlate the test result data to the analysis result data. Eventually damage tolerance design concept will be used for an aircraft development with increased structure integrity and reliability. |
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| Key Words |
| Fractographic analysis, Fatigue Life, Damage tolerance |
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