If you want to weld steel to a metal boat go with what the shipping industry uses for their containers to insure long life and corrosion resistance.
https://en.wikipedia.org/wiki/Weathering_steel
Printed copy · Anthology Volume 1, page 398Printed copy from The Tender For Law Anthology, Volume 1, page 398 (printed 14 June 2014). Added by this site; not part of the Facebook export.