virtues of titanium

[soilent green]

I would like to now if it would be possible to make a valve for any mag from titanium and aluminum I would like to know the difference in strength between titanium and stainless I think titanium is about 60% the weight of SS so a titanium and aluminum valve could possibly be half the weight so what is the technical possibility of this I'm sorry if this isn't a deep blue subject but I'm hopeing for responsis other than "that would be cool"

[Redkey]

materials properties

why would you want to do this?

Ever heard of galvanic corrosion? Aluminum and Titanium do not really get along too well when in close contact with each other. The aluminum will slowly corrode away.

now the properties....

Stainless Steel
density=7.75-8.1 g/cc
modulus=190-210 GPa
Tensile str=515-827 MPa
Tensile yield = 202-552 Mpa

Aluminum
density = 2.6-2.8 g/cc
modulus = 70-90 GPa
Tensile str = 230-570 MPa
Tensile yield = 215-505 Mpa

the wide range of mechanical properties is due to all the heat treatment options for steel and aluminums

Titanium
density=4.5 g/cc
modulus=100-120 GPa
Tensile str=234 MPa
Tensile yield = 138 Mpa

[soilent green]

I know about galvanic corrosion but I didn't titanium interacted with aluminum so badly I really was just thinking of saveing wait but it would seem that the weight saveing benefits are negated by stainlesses supeirior strength, corrosion resistence, and over all quality

[Cha0tic]

Tom mentioned in an earlier post....

AGD made some tianium valves. they had very little effect on the weight of the marker. they got mixed up with regular valves and shipped away.

[BlackVCG]

Here's a discussion on titanium and the idea of it being used for a bolt.

http://www.automags.org/forums/showthread.php?s=&threadid=25340

[Wat]

the weight savings switching to titanium are so marginal. If you want to save weight, i suggest you go to the gym and burn some fat off. Not only will it lighten your load making you move faster, it will make you a smaller target, longer life expectancy, healther lifestyle and chicks generally find it more appealing.

And if you already have a 8% body fat, the gun should feel light to you already.

I've said it before, the amount of money people are willing to pay for that marginal 1% performance is obscene. I'm in the wrong industry.

[BlackVCG]

Wat- You took the words right out of my mouth. :)

[Doc Nickel]

Bravo, Wat.

I've seen guys complain about how much heavier their stainless barrel is over an aluminum one, but then they have a 114 ci tank and a 12V Rev on their gun and they only shoot 400 rounds a game.

And Redkey; yes, you're right that galvanic corrosion could, theoretically take place. But Titanium is nowhere near as reactive as steel, brass, copper or aluminum.

Even if you had a brass/aluminum mix, and neither one was plated (anodizing almost eliminates galvanic action, since it's nonconductive) you'd still need a wetting agent to help the oxygen react. Moisture from rain or paint spray would do it- salt water's bad because it's more conductive.

Suffice to say you could have an aluminum/brass, a titanium/aluminum, or a titanium/brass valve, and you'd probably never see any more galvanic reaction other than a little tarnishing.

Put it this way- when's the last time you saw any galvanic corrosion where the brass power tube tip meets the stainless steel valve body?

Doc.

[steveg]

Furthermore Red you show the mechanical properties for
pure titanium only. tensile strenght can be as high
as 1380 MPa (1 MPa = 145.038psi) for alloyed and heat treated Ti

Steel and stainless are by definition alloys (of iron)
aluminum with the exception of beverage cans is almost always an alloy.

titaniums downfall is that it doesn't wear well (rubbing friction)

[Redkey]

well....

hmmm.... "furthermore"? i feel like I have been scolded...

The galvanic corrosion rates between Al and Ti may be slow but it still occurs. I guess in a PB gun with oiled parts it wouldn't be a significant issue... I'm used to working in a more corrosive environment, salt and de-iceing chemicals are evil corrosion promoters.

You're right about the Ti alloys I should have used the proper values. I thought it looked a bit on the low side.

Thanks for the correction.

[soilent green]

hey guys I'm not really complaining about the weight I was more woundering what the possibilities were and what you all thought about it I really do appreciate the quality AGD puts into their guns and the use of stainless is included in that I however did not realize that the waight savings were that insignificant and redkey thank you for at least going to the trouble of looking up the properties for me us and as for galvanic corrosion I don't beleive it is any worse than brass and stainless which is already in the mag valve

[Conqueror]

Well, the possibilities are high, but they aren't too realistic. Ti is a fairly strong metal, but it's heavier (2x) than Aluminum. To see any weight loss, you'd have to machine it till it was damn thin, which would be very difficult given that A) it's hard to machine very thin items, and B) Titanium is an absolute btch to machine.

Peace.

CQ

[DaveK]

Titanium Bolt Question

To Soilent Green and Redkey-
Re: Galvanic corrosion Ti vs. al-
When you see the material callout for Titanium on a mechanical drawing, you'll see something like: "Ti 6al4v".
Aluminum and Vanadium (a metal found in uranium ore) are used as alloying agents to alter various properties of titanium. In the example, this version of Titanium contains 6% aluminum and 4% vanadium. So galvanic corrosion between a part made of titanium that contains some aluminum, and another part that is only aluminum, if it had any negative effect at all, would affect the aluminum part. And that would depend upon the purity of the aluminum alloy. If it is pure 1100 alloy, there would most likely be no corrosion on either part.

[eskimo]

What about magnesium, they use mag/aluminum in the construction of race wheels for cars. Extremely strong, and very light weight.

[Hamster Huey]

Aluminum, steel, 6/4 Ti, heat-treating, strength-to-weight ratios - if I didn't know better I'd suspect that I had accidentally loaded up a mountain biking page. Even Wat's comment fits right in.