Will titanium corrode if wrapped?

[TECH]

I don't think it will.  I'm thinking of wrapping my Ti-Force pipe, for a couple of reasons.  It'd be good to keep the exhaust heat out from under the bike, which will keep everything cooler, especially the oil pan.  Also, I want the thing to get hot enough to turn the exposed pipes a solid blue color.  It looks really good, but if it doesn't get hot enough, it's an ugly brown color.    I think the only problem I may have is the springs rusting, but they don't last long anyway.....    Any input is appreciated.

[ZXALAN]

TECH do not wrap your pipe.  I can give you many reasons why not to,  remember when you first saw my big bird I had it wrapped? I pulled that shit off in two months and the pipe had surface rust and corrosion all over it.  Ti is very fragile,  it would eat a hole in that shit in no time.  I would not do anything to it at all.  Not to mention the wrap will burn your plastics more!  TRUST ME!  Don't wrap it!  

[SJJBusa]

If you wrap the entire header, it will not corrode, it will MELT. Titanium & heat do not mix too well. I installed a Ti Force pipe on my friends 02 busa, and used wrap only in a couple of places where the pipe was too close to the bodywork. Also, make sure that you get a couple of spacers from Orient Express for the cross brace that connects the lowers down in the front. Without the spacers, the bodywork will touch the header.

SJJBusa

[TECH]

Yes Alan, I remember your postings on the subject.  I was just wondering how Ti would react as compared to stainless.
SJJ, you really think it will melt?      
I lengthened my fairing strap to make clearance on the pipes, so no problems there.  No burning at all.  
Thanks.

[BigFatBusa]

I thought that the high melting point of titaniun is was what makes it so expensive

[len]

if you wrap it, it will work fine, untill it destroys your pipe from the excess heat. thats true with all pipes regardless of material. personally I wouldnt, not for the small gain, especially on a street bike,  

[SJJBusa]

The Ti Force pipe material is only 1mm thick. You do not need to take my word for it, ask any manufacturer of ti pipes. You also don't want to coat the pipe either.

Regards,

SJJBusa

[Ct Chip]

I bought a 2002 new in March. Had a Ti Force on it since mile one coated inside and out. 7500 miles later it's just like new, no problems.

[TECH]

quote:Originally posted by Ken:
I thought that the high melting point of titaniun is was what makes it so expensive

I always figured it was the high strength and low weight ratio.

[TECH]

quote:Originally posted by SJJBusa:
The Ti Force pipe material is only 1mm thick. You do not need to take my word for it, ask any manufacturer of ti pipes. You also don't want to coat the pipe either.

Regards,

SJJBusa

I know it's thin, and why shouldn't I coat it?  Just curious.

[ZXALAN]

Because the coating will HELP keep the heat in the pipe, it will burn itself from inside out.  Ti is VERY fragile, thats why it dents and dings so easy.  I have seen one on a busa that the owners girl friend's boot missed the peg and hit the pipe and CRATERED it.  I would leave it alone.  Ti has to relieve heat quickly, its thin and weak, thats why its so light.  Plus it really doesn't make that much difference in the engine bay with the pipes wrapped.  I may ceramicoat my header and collector but leave the mid pipe polished.

[Rocket Man]

I've heard it from several people. If you wrap a ti pipe, you will destroy it. It can't take the heat, I think was the reason.

[mis4tun81]

You can find everything on the net:

 Titanium Info

High temp looks to be the killer. Doesn't melt or burn, but becomes brittle, which becomes more agressive right at high exhaust temps.

L8r

[mis4tun81]

Heres the important part

Resistance to gases

Titanium alloys perform well in many aggressive environments:

Oxygen and air
Titanium alloys are totally resistant to all forms of atmospheric corrosion regardless of pollutants present in either marine, rural or industrial locations. Titanium has excellent resistance to gaseous oxygen and air at temperatures up to 370°C (700°F). Above this temperature and below 450°C (840°F), titanium forms colored surface oxide films which thicken slowly with time. Above 650°C (1200°F) or so , titanium alloys suffer from lack of long-term oxidation resistance and will become brittle due to the increased diffusion of oxygen in the metal. In oxygen, the combustion is not spontaneous and occurs with oxygen concentration above 35% at pressures over 25 bar (350 psig) when a fresh surface is created.

Nitrogen and ammonia

Nitrogen reacts much more slowly with titanium than oxygen. However above 800°C (1400°F), excessive diffusion of the nitride may cause metal embrittlement. Titanium is not corroded by liquid anhydrous ammonia at ambient temperatures. Moist or dry ammonia gas, or ammonia water(NH4OH) solutions will not corrode titanium to their boiling-point and above.

Hydrogen

The surface oxide film on titanium acts as a highly effective barrier to hydrogen. Penetration can only occur when this protective film is disrupted mechanically or broken down chemically or ectro-chemically. The presence of moisture effectively maintains the oxide film inhibiting hydrogen absorption up to fairly high temperatures and pressures. On the other hand, pure, anhydrous hydrogen exposures should be avoided particularly as pressures and/or temperatures increase.

The few cases of hydrogen embrittlement of titanium observed in industrial service have generally been limited to situations involving high temperatures, high alkaline media; titanium coupled to active steel in hot aqueous sulphide streams; and where titanium has experienced severe prolonged cathodic charging in seawater.

Penetration Diffusion of hydrogen into titanium is very slow at temperatures below 80°C (176°F) except where high residual or applied tensile stresses exist. If the solubility limit of hydrogen in titanium is then exceeded, (100-150 ppm for commercially pure Grade 2), titanium hydride will begin to precipitate. At temperatures not exceeding 80°C (176°F), hydride will normally be restricted to the surface layers of the metal and experience in such cases indicates that this has little or no serious effect on the performance or properties of the metal. Cases of through section hydride formation, leading to embrittlement and cracking or failure under stress are very rare. Hydriding can be avoided by the proper design of equipment and control of operating conditions.

[mis4tun81]

If you keep it between 700 and 840 Farenheit

you can get the pretty colors you want

Titanium has excellent resistance to gaseous oxygen and air at temperatures up to 370°C (700°F). Above this temperature and below 450°C (840°F), titanium forms colored surface oxide films which thicken slowly with time.

[mis4tun81]

Whoring now

  It also says the surface oxide is "self healing"
in air, and its this Oxide which is titaniums first line of defense, kind of like aluminum.  so it looks like if you coat it, or wrap it, the Oxide can't reform, agregating the problem.

[racedrvr]

I used Jet-Hot ceramic coating and it did what wrapping the pipe will do. Allow the heat to be carried down the pipe rather than dissapating heat near the inlet of the header through radiation of the hot pipe. The coating is on the INSIDE of the pipe as well as external so it allows the heat in the exhaust to be carried downstream. It will not cause the metal to get hotter as it is coated on the inside.
Your exhaust cannister should get hotter with a coated pipe, as the exhaust will not cool down like it does in an uncoated pipe. I have been running a coated pipe since last year with only positive results--including lots of racing WFO.