**4. Conclusions**

The effects of natural aging on stress corrosion cracking in A201-T7 alloy were investigated in this study and the following conclusions can be drawn:


**Author Contributions:** Data curation, Writing—original draft preparation, M.-C.C.; Conceptualization; Methodology, M.-C.W.; Performed experiment, Formal analysis, T.-A.P.; Investigation; Validation, Y.-C.C.; Project administration, Resources, Y.-C.T.; Supervision, Funding acquisition, Review and editing the draft, S.-L.L. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research was funded by the National Chung-Shan Institute of Science & Technology (Contract: XV07116P418PE-CS).

**Acknowledgments:** The author would like to thank Tsai-Fu Chung from National Taiwan University for the TEM observation.

**Conflicts of Interest:** The authors declare no conflict of interest.
