jbog - Your explanation is better than mine! (I'm afraid you've awoken long dormant brain cells associated with taking physical chemistry and material science in college that used to cause me to have nightmares.) Hopefully no one will use steel wool on their Cybertruck to get out any rust that does appear!
I didn't know that the rust/corrosion resistance of SST came mostly from passivation and only partly from the grade. (My only experience with passivation is that it was something to have an instrument tech do to a "leaky valve seat"- now I understand why and that is really good info to me).
I don't know either why Tesla cold rolled whatever grade of SST they start with to get more strength and importantly rigidity. As I understand it, the design precludes the use of crumple zones which have historically been needed to attain a 5-star safety rating. The National Highway Transportation Safety Administration (NHTSA), and the Insurance Institute of Highway Safety (IIHS) hasn't tested the Cybertruck because there haven't been that many made or in circulation. I wonder what rating it would get if they did test it. (Automakers do need to do internal test to assure meeting federal minimum standards but that doesn't mean you would get a "5-star" rating from NHTSA/IIHS.) It would be another blow to the Cybertruck mystique if it got less than a 5-star rating.
"People are best convinced by reasons they discover themselves"
AI
