[rland]

You can’t just replace a material like that in something as large as a ship.

You need to have the right toughness, ductility, fatigue, etc.

Steel varies a lot. You can buy a 1000 page book that just lists different steels, along with their material properties.

Saying “just use stainless” is kinda like saying “just 3d print it” or “just make it out of carbon fiber”