PSI - Issue 23

A.A. Shanyavskiy et al. / Procedia Structural Integrity 23 (2019) 57–62 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

62

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Tests were performed up to the lifetime when blade frequency has fallen down on 2% after the α -criterion was registered. Statistical analysis of received tests data has shown the good correlation between analyzed values in the next form:     ae t ae N N blades rotor MPa for 3.897 0.717lg ), lg (26 260    (13)     ae t ae N N blades rotor MPa for 4.114 0.55lg ), lg (28 280    (14) The same results were discovered for another type of blades manufactured from superalloy VJL8 having another shape of γ’ phase:     ae t ae N MPa N for 2.786 0.666lg lg 260    (15)     ae t ae N MPa N for 3.0 0.439lg lg 280    (16)

5. Summary

Different cases of AE-signals using for diagnostics of blade durability or lifetime for crack origination registration discussed above have shown that blades of various superalloys can be attested during the repairing procedure. Using such diagnostic parameters for estimating blade state as summarized AE-signals or signals energy can resolve the problem not only for material state diagnostics with fatigue crack detection placed, for example, by the inner surface but it can be realized diagnostics of blades durability for repaired units.

References

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