ScaredyCat
Expert Class
Posts: 201
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posted June 27, 2003 05:54 AM
Does Titanium corrode?
Well, like the title says, if I spend a shitload of cash on titanium bolts and stuff, are they going to last longer than stainless? A few milligrams of weight saving don't equal 10 bucks in my (check)book.
:-)
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VincentHill
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posted June 27, 2003 06:24 AM
Spend less and buy Stainless. The Bottle of Pop you drank is the difference
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deathpulse
Pro
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posted June 27, 2003 06:24 AM
I think Ti (depending on the composition) does corrode - just a LOT slower than other metals. Also, when working on Ti (at least in aircraft) I think there are special tools that are used (steel tends to react poorly with Ti??) Can anyone confirm this?
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your car is slow
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posted June 27, 2003 06:50 AM
not that im a metal expert or anything...but that stuff is used in Submarine hulls.....if a metal can be immersed in a salt water bath for its entire life and not corrode....I think its safe to use on the bike 
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dougmeyer
Needs a job
moderated
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posted June 27, 2003 07:06 AM
 Edited By: dougmeyer on 27 Jun 2003 08:16
Titanium oxidizes only at very high temperatures (like over 1600F). At temps you'll ever see it's basically inert (non-reactive). Ever see a rusty SR-71? 
The tool story arises from the fact that when working on SR's, mechanics used bronze and aluminum tools because they were softer than the Ti to avoid scratches and dings that could start a fault at Mach 3 and the skin temp was 900F.
Doug
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Ed_00_12R
Novice Class
Posts: 54
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posted June 27, 2003 07:25 AM
quote:
Titanium oxidizes only at very high temperatures (like over 1600F). At temps you'll ever see it's basically inert (non-reactive). Ever see a rusty SR-71?
The tool story arises from the fact that when working on SR's, mechanics used bronze and aluminum tools because they were softer than the Ti to avoid scratches and dings that could start a fault at Mach 3 and the skin temp was 900F.
Doug
Sounds like we need bronze tools then. Wouldn't want to have any high speed scratch-induced aerodynamic instabilites ya know.
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Ed
2000 ZX12R
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your car is slow
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Fuck Nitrous...Got Boost?
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posted June 27, 2003 07:26 AM
thats weird....that would mean you can cut it with an acetylene torch? You cant even get stainless to oxidize with an ace torch....I think that gets up to what...5500 degrees? Would this mean stainless actually stands up better to oxidation than ti?
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frEEK
Administrator
ummm... yeah
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posted June 27, 2003 10:01 AM
if i remember my 1st year chemical classes correctly, Ti is actually fairly poor at real high-heat applications. it just doesnt stand up well to heats that other metals like stainless can take. semes to me Ti has been hyped like a friggin movie or some other commercial product. it's strong & lightweight, yes, but it aint no miracle metal. it's a real bitch to manufacture too, which is where most of the manufacturing cost comes (came?) in. i seem to remember it has to be smelted in oxygen free rooms, because a single molecule of oxygen can cause a serious fault. in fact, there was a rather well known passenger airliner crash some 10 or 15 years ago which was all started by a single fan blade shattering. they eventually found the remnants of the piece at fault, and found a tiny imperfection from an oxygen mulecule that caused the fracture.
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harryzx-12
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posted June 27, 2003 02:15 PM
You probably need to be more worried about dissimiliar metal corrosion (titanium when used with aluminum).
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kcadby
Pro
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posted June 27, 2003 04:53 PM
Harry works on airplanes!!! HE should know!!!
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dougmeyer
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posted June 27, 2003 07:20 PM
Titanium is very stable and strong at high heat BUT it will oxidize quickly in an oxygen atmosphere above 1660F. Remember what we're using is not pure titanium but one of a couple alloys commonly including aluminum and vanadium (Ti Al V). In pure oxygen, pure titanium burns (complete oxidation) at 1130 F. Less oxygen and the alloying raises that temp. Melting is a different story, IN an inert atmosphere pure titanium melts at 3020F and boils (try that) at 5949F. Conversely Ti is very brittle when very cold. At low "red heat" it's very workable and malleable. I got more if you want it....
Doug
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frEEK
Administrator
ummm... yeah
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posted June 27, 2003 07:54 PM
i take it the alloying helps make the Ti less brittle too?
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deathpulse
Pro
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posted June 27, 2003 08:14 PM
OMG. We are in trouble - when my '12 is at max velocity I must be at what... say mach 3 or 3.5??? DAMN. Better get composite parts.... =P. Just kidding - great info Doug (as always)! Looks like we are good to go with the Ti parts on the '12.
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ZHooligan
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posted June 27, 2003 08:22 PM
I use anti-sieze with my Ti-fasteners and have never and I mean never an issue.
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slug
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posted June 28, 2003 03:24 AM
hrmmthe problem with titanium hulled subs (russians payed with them) is that they work-harden....
sooo if they take the sub down to 1000ft once, they can't go that deep again....
it reaches a point where it stabilizes, but that's because the material is too hard...
corrosion at normal temperatures again isn't much trouble, but they DO have trouble with sea-growth....critters love Ti ;P
and someone that has worked it can answer this: does welding Ti form toxic gases? i had heard that, and they told us it was why they used flanges instead of welding....
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12RPilot
Pro
Posts: 1094
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posted June 28, 2003 05:44 AM
Just in case, I'm not going to weld my Ti fasteners 
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