Comments by "Vikki McDonough" (@vikkimcdonough6153) on "A Brief History of Naval Armour - Successfully Forging Onwards" video.

14:07 - The breaks-if-you-bend-it-back-and-forth-over-and-over-again property of an iron nail isn't due to work hardening (at least, not directly); it's due to metal fatigue. This can be seen from the fact that the nail gets easier and easier to bend (due to fatigue cracks occupying an increasingly-large proportion of its cross-sectional area) before it finally breaks; if the breakage were due to the bending work-hardening the iron, the nail would get progressively stiffer and harder to bend before the final fracture. Speaking of which, I wonder if metal fatigue was an issue for the armor plating of ships that survived numerous engagements?
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