Originally Posted by denverd0n
Already mentioned, but I will summarize...
Stainless steel needs exposure to oxygen, or it is very little more "stainless" than carbon steel. Stainless steel is more brittle, and more subject to work
hardening, than carbon steel. Both of these characteristics make it less than optimal for a boat hull
, and certainly not worth the additional cost. This is why you do not see it commonly used.
While your comments may apply to 316 stainless steel which is unsuitable for use underwater, it does not apply to duplex stainless which was approved by Lloyds for Tanielle`s hulletc.
Also duplex is not brittle and has far higher fatigue strength (resistance to work hardening), than mild steel.
While the addional cost over mild steel is substantial, it is in fact regained the first time the mild steel hull
has the entire interior
stripped and repainted. This is why mild steel yachts do not hold a high resale value.