High Tensile Steel for boat building

[H2O_BABIES]

Is High Tensile steel more easy to work on and lighter, would we use less material if we convert from mild steel to HTS?

[globaldude]

Hi water babies, HTS is harder to work with, [ can be a real mongrel with compound curves ] it's only lighter, if it's a lighter gauge, you'd use the same square meters naturally, but the boat would be lighter.
HTS is more brittal, less ductile - which could lead to stress fractures, especially if one happens to bounce on a reef oneday !!.
It's a no no to " patch " HTS with mild steel [ you would in an emergency ] so having bounced across said reef, it may be hard to find maching material localy to efect a "proper " repair.
You'd most likely use low hydrogen welding rods, which definately require more skill to use .
I think, with the thinner gauge [ if you used it ] you'd be more prone to distortion throughout the hull .
corten has a higher copper content & after some initial rust, will rust slower [ but who wants a rusty boat [ unless you like to scare off other, shall we say, fragile boats ! . LOL ]

[SeaSpark]

Corten or "Cor-Ten", Corrostion resistance Ten, was developed with boatbuilding in mind and is used often for it.

Like aluminum it forms a layer of corrosion rapidly that protects the steel below it. Rust stains are not nice on a boat but when build of corten these stains will not grow as rapidly as with normal steel. Reparing the paint job will only be necessary for aesthetic reasons.

[Mayfly]

What about Cor-Ten compare with mild steel on it ability to survive a hit or bounce?

[globaldude]

Just rang my engineering buddy to yak about Cor-ten, which he uses often for truck decks & the like.
We are both of the opinion that Cor-ten is a Medium tensile steel [ as opposed to high tensile, or mild steel] and we know it to be much stronger.
In New Zealand it's only slightly dearer than mild steel, about 20 $30 per sheet.
3mm Cor-ten seems [ I say seems as this is our experience, not calculations from an engineer ] to have about the same strength as 4mm mild steel.

So why wouldn't you use it in place of mild steel ?? ---- given that, and [in my opinion] answer to your question , it's stronger and therfore more able to withstand an impact / bounce .

Ahoy you teco engineering types, any problem with you're aware of, joining, say cor-ten decks to mild steel hull ?? , electrolisis ? --- I think I'll post this ? elsewhere as well to get an answer. I'm about to build new decks on an exsisting mild steel hull .
I stand by my opinion regards to high tensile - brittle, work hardens - no thanks.
Pete.