PSI - Issue 14

M S Nandana et al. / Procedia Structural Integrity 14 (2019) 314–321 M S Nandana/ Structural Integrity Procedia 00 (2018) 000–000

321

Conclusions:

Based on the present study relating the variation in microstructure to the fatigue crack growth behavior in 7010 aluminum alloy subjected to T6 and RRA conditions, the following conclusions are derived:  The increase in threshold stress intensity factor range from 8.25 MPa√m in T6 condition to 9.33 MPa√m in RRA treated condition could be achieved.  An ultralow fatigue crack growth rate in the near-threshold regime could be obtained which is 2-3 times lower than that observed in the T6 treated sample.  The RRA treatment applied on A-Zn-Mg-Cu alloys improved the damage tolerance properties which is beneficial for aircrafts structural parts subjected to service loads.

Acknowledgements

The authors are thankful to The Director, NITK and the Director, CSIR-NAL, for facilitating to conduct this research work and also for their continuous encouragement.

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