Need Ti explaination...

[Crystal]

Greetings all... can someone please explain the difference between 3Al/2.5V titanium and
6Al/4V titanium.

Thanks Crystal

 

[Kbh]

Seven's brochure talks about it:

http://www.sevencycles.com/

"Crystal" <[email protected]> wrote in message news:[email protected]...
> Greetings all... can someone please explain the difference between
3Al/2.5V
> titanium and 6Al/4V titanium.
>
> Thanks Crystal

 

[Crystal]

Seven has a great website, except that they will only send me their brochure "within the next
few weeks"...

Anyone else has an explination?

Thanks Crystal

 

[G. Huang]

Crystal wrote:
> Seven has a great website, except that they will only send me their brochure "within the next few
> weeks"...
>
> Anyone else has an explination?
>

Both are Ti Alloys. 3Al/2.5V = 3% Aluminum and 2.5% Vanadium 6Al/4V = 6% Aluminum and 4% Vanadium

6Al/4V has about 40% higher tensile strength and slightly higher Young's modulus.

GH

 

[Skuke]

Try http://www.habcycles.com/techstuf.html

Strictly speaking, 3Al/2.5V has Ti with 3% Aluminum and 2.5% Vandium. You can guess what 6AL/4V is
comprised of.

skuke

"Crystal" <[email protected]> wrote in message news:<[email protected]>...
> Seven has a great website, except that they will only send me their brochure "within the next few
> weeks"...
>
> Anyone else has an explination?
>
> Thanks Crystal

 

[Bfd]

"Crystal" <[email protected]> wrote in message news:<[email protected]>...
> Seven has a great website, except that they will only send me their brochure "within the next few
> weeks"...
>
> Anyone else has an explination?
>
Here's some reading material: seven - http://www.sevencycles.com/technology/techtitantypes.html

habanero - http://www.habcycles.com/techstuf.html

Spectrum-cycles - http://www.spectrum-cycles.com/624.htm

Note - none of the above builders use 6/4 tubing, so there will be bias against. For pros, contact
litespeed....

 

[Chalo]

"Crystal" <[email protected]> wrote:

> can someone please explain the difference between 3Al/2.5V titanium and 6Al/4V titanium.

Compared to 3/2.5, 6/4 Ti has a higher tensile strength-- by about a third-- and lower
ductility, much the same way that high carbon steel has higher strength and lower ductility that
mild steel. 3/2.5 and
6/4 have functionally identical density and stiffness.

7/4 is easier to machine (cuts more cleanly) while 3/2.5 is easier to form (takes a tighter bend
without cracking). So 3/2.5 is more suitable for drawing into tubes, while 6/4 is superior for
dropouts, threaded bosses, cable stops and the like.

There has been a great deal more hype about differentiating between these alloys than is warranted
by their properties. There are processing implications for the manufacturer, but no practical
distinctions for the end user.

Chalo Colina

 

[Steve Hambley]

> There are processing implications for the manufacturer, but no practical distinctions for the
> end user.
>

Except Cost! Steve

 

[David L. Johnso]

On Mon, 16 Jun 2003 15:30:35 +0000, bfd wrote:

> Note - none of the above builders use 6/4 tubing, so there will be bias against. For pros, contact
> litespeed....

Probably true. None of these sites (Sorry, Mark) is unbiased, in that they sell one or the other,
and want to encourage you to buy theirs. Mark (Hickey, Habanero) does have one useful point, though.
That is the gram/$ ratio. For a frame of comparable strength, the difference between 6/4 and
3/2.5 will be small in terms of grams, but big in terms of dollars.

Is it worth it to you? That is the decision to make. I have seen a frame that was claimed to be made
of 6/4 alloy with seamless tubes. Most 6/4 tubes are not seamless, but rolled and welded. That
clearly has problems in terms of weld imerfections. If indeed they have seamless tubes now, then
that disadvantage is gone, if you are willing to pay for it.

For me, the money did not buy happiness, and I went for one of Mark's frames. Nice, well-made, great
ride. You choose.

--

David L. Johnson

__o | The lottery is a tax on those who fail to understand _`\(,_ | mathematics. (_)/ (_) |

 

[Mark McMaster]

bfd wrote:
> "Crystal" <[email protected]> wrote in message news:<[email protected]>...
>
>>Seven has a great website, except that they will only send me their brochure "within the next few
>>weeks"...
>>
>>Anyone else has an explination?
>>
>
> Here's some reading material: seven - http://www.sevencycles.com/technology/techtitantypes.html
>
> habanero - http://www.habcycles.com/techstuf.html
>
> Spectrum-cycles - http://www.spectrum-cycles.com/624.htm
>
> Note - none of the above builders use 6/4 tubing, so there will be bias against. For pros, contact
> litespeed....

Merlin and Litespeed Titanium are both titanium bicycle brands and are both owned by the American
Bicycle Group (http://americanbicycle.eu.com/home.html). Both brands are produced in the same
factory in Chattanooga, Tennessee.

All frames that carry the Merlin name are made from 3Al/2.5V Ti, which the Merlin web pages say is
the superior alloy for use in bicycle frames:

http://www.merlinbike.com/english/tech/ti_history.html#grades

However, several Litespeed models at the top end of their price scale are made from 6Al/4V ti, which
the Litespeed web pages say is the superior alloy for bicycle frames:

http://www.litespeed.com/english/technology/titanium.html
http://www.litespeed.com/english/bikes/vortex.html

Which half of the American Bicycle Group factory is fooling the other half?

Mark McMaster [email protected]

http://americanbicycle.eu.com/home.html

 

[Bfd]

Mark McMaster <[email protected]> wrote in message news:<[email protected]>...
> bfd wrote:
> > "Crystal" <[email protected]> wrote in message
> > news:<[email protected]>...
> >
> >>Seven has a great website, except that they will only send me their brochure "within the next
> >>few weeks"...
> >>
> >>Anyone else has an explination?
> >>
> >
> > Here's some reading material: seven - http://www.sevencycles.com/technology/techtitantypes.html
> >
> > habanero - http://www.habcycles.com/techstuf.html
> >
> > Spectrum-cycles - http://www.spectrum-cycles.com/624.htm
> >
> > Note - none of the above builders use 6/4 tubing, so there will be bias against. For pros,
> > contact litespeed....
>
> Merlin and Litespeed Titanium are both titanium bicycle brands and are both owned by the American
> Bicycle Group (http://americanbicycle.eu.com/home.html). Both brands are produced in the same
> factory in Chattanooga, Tennessee.
>
> All frames that carry the Merlin name are made from 3Al/2.5V Ti, which the Merlin web pages say is
> the superior alloy for use in bicycle frames:
>
> http://www.merlinbike.com/english/tech/ti_history.html#grades
>
> However, several Litespeed models at the top end of their price scale are made from 6Al/4V ti,
> which the Litespeed web pages say is the superior alloy for bicycle frames:
>
> http://www.litespeed.com/english/technology/titanium.html
> http://www.litespeed.com/english/bikes/vortex.html
>
> Which half of the American Bicycle Group factory is fooling the other half?
>
>
I say neither. ABG is covering all bases so that if the consumer *believes* 3/2.5 is superior, they
can buy either merlin or litespeed. Similarly, if the consumer *believes* 6/4 is superior, they got
that covered. Either way, ABG has what people want and should make money on both....

 

[David E. Belche]

"David L. Johnson" <[email protected]> wrote in message
news:<[email protected]>...

> I have seen a frame that was claimed to be made of 6/4 alloy with seamless tubes. Most 6/4 tubes
> are not seamless, but rolled and welded. That clearly has problems in terms of weld
> imerfections. If indeed they have seamless tubes now, then that disadvantage is gone, if you are
> willing to pay for it.

6/4 Ti tubing is available in seamless, double-butted form from Reynolds, and features in Airborne's
new flagship Torch frameset. As you say, though, it will make a big dent in your wallet.

David E. Belcher

Dept. of Chemistry, University of York

 

[John Carrier]

Refers to percentage of Aluminum and Vanadium in the Ti alloy. 6/4 has higher tensile strength but
nearly identical modulus of elasticity (the same spec tube in 6/4 and 3/2.5 will have the same
flexibility ... but the 3/2.5 will fail under a lesser ultimate load). Theoretically, you could
manufacture a 6/4 frame that was lighter than 3/2.5. If advertised weights are reasonably accurate,
this isn't true in practice. Theoretically, the
6/4 frame could be stronger than a similar 3/2.5 frame. Doesn't appear to be meaningful in practice.

7/4 tends to get brittle when cold-worked and is difficult (impossible) to draw into tubes. Most 6/4
frames are fabricated from sheet and welded into (and sometimes cold-worked into multishape)
tubes. Arguably, cold-working has a detrimental effect on fatigue strength, but that doesn't
appear to be demonstrated in bicycle applications. Many frames use 6/4 for rear dropouts. Other
fittings are usually CP (commercially pure) Ti.

I assume that your question is to support a purchase decision. Either alloy can be made into an
excellent frame. Neither variation of Ti, on the merits of the alloy alone, will result in a
"better" product.

R / John

"Crystal" <[email protected]> wrote in message news:[email protected]...
> Greetings all... can someone please explain the difference between
3Al/2.5V
> titanium and 6Al/4V titanium.
>
> Thanks Crystal

 

[Jasper Janssen]

On Fri, 20 Jun 2003 07:02:41 -0500, "John Carrier" <[email protected]> wrote:

>Refers to percentage of Aluminum and Vanadium in the Ti alloy. 6/4 has higher tensile strength but
>nearly identical modulus of elasticity (the same spec tube in 6/4 and 3/2.5 will have the same
>flexibility ... but the 3/2.5 will fail under a lesser ultimate load). Theoretically, you could
>manufacture a 6/4 frame that was lighter than 3/2.5.

But then it'd be flexier, wouldn't it? Thinner walled tubes?

Jasper

 

[Mark Hickey]

Jasper Janssen <[email protected]> wrote:

>On Fri, 20 Jun 2003 07:02:41 -0500, "John Carrier" <[email protected]> wrote:
>
>>Refers to percentage of Aluminum and Vanadium in the Ti alloy. 6/4 has higher tensile strength but
>>nearly identical modulus of elasticity (the same spec tube in 6/4 and 3/2.5 will have the same
>>flexibility ... but the 3/2.5 will fail under a lesser ultimate load). Theoretically, you could
>>manufacture a 6/4 frame that was lighter than 3/2.5.
>
>But then it'd be flexier, wouldn't it? Thinner walled tubes?

The flex would be identical between the two alloys, if all other things are equal. The tradeoff is
between ultimate strength and ductiliity (or more accurately, plastic deformation). 6/4 has higher
ultimate stength than 3/2.5 (which makes it harder to tear the tubes in half - not normally a big
problem for well-built frames of either alloy), but 6/4 has considerably less ductility. Plastic
deformation is a measure of how far you can bend a piece of material before it's permanently
deformed, and 3/2.5 has a distinct advantage there.

If you push the envelope too far with either alloy by making the tubes thinner and thinner, you
increase the flex. If the resultant flex is beyond the material's ability to "spring back", you have
a misaligned frame.

Mark Hickey Habanero Cycles http://www.habcycles.com Home of the $695 ti frame

 

[Appkiller]

<snip)
> 6/4 tends to get brittle when cold-worked and is difficult (impossible) to draw into tubes.
<snip>

Reynolds is making seamless 6/4 tubing. Butted as well, I believe.

App

 

[John Carrier]

Theoretically, you could
> >manufacture a 6/4 frame that was lighter than 3/2.5.
>
> But then it'd be flexier, wouldn't it? Thinner walled tubes?

No, you could use your higher strength material to make a slightly larger diameter and slightly
thinner-walled tube that would be overall lighter and just as stiff.

R / John

 

[John Carrier]

I stand corrected. Meant to say "almost impossible." Reynolds, who frequently come up with
innovative tube drawing solutions do make seamless
6/4 tubes.

R / John

"Appkiller" <[email protected]> wrote in message
news:[email protected]...
> <snip)
> > 6/4 tends to get brittle when cold-worked and is difficult (impossible)
to
> > draw into tubes.
> <snip>
>
> Reynolds is making seamless 6/4 tubing. Butted as well, I believe.
>
> App