Trying to do the lightweight stuff, I saw some rims in a magazine( dunno which one ?) and they had the word titanium next to them, would this be the rim is made of titanium or is that just a description of the color of the rim? I saw the ad really quick.

 

Your question will be better answered in the correct forum. Thread moved.

 

It's a description of color. Wheels are only made from aluminum alloy, steel or magnesium.

 

one thing tho. it was the color, but the idea of titanium rims.

Ti = 47.867g/mole
Al = 26.98 g/mole

basicly what Im saying is that Ti is a great material thats really strong, but forged aluminum is lighter, not stronger, but lighter, and strong enough for typical use.

only way to go any lighter than forged aluminum is carbon fiber. which is really really cool, cause they often are a solid peice from CF rotor to rim, meaning the rim is a giant heat sink for your brakes.

 

Where can I buy these for my Z?

 

cant use em on the street, theyd be trashed by the time you got down your driveway. they dont have that much strength. I think someone might have made them with a cf lip or cf spoke or something.... it wasnt all cf, only partially, not sure if that was for street use either tho.

 

Ares - You really don't know what you are talking about. Carbon fiber is not going to create some magic heat sink for your brakes. The specific heat capacity and the thermal conductivity of a CF wheel will be much lower than a comparable metal wheel. And carbon fiber is used quite often in aftermarket rims for motorcycles, which I agree don't have to be as strong as a car rim.

As for titanium versus aluminum, you can't just look at the density. The strength to weight ratio is a better metric to use. In other words, titanium is denser but you can use less of it because it's stronger. (One source I found says titanium has a 74% greater strength to weight ratio than 6061-T6 aluminum.)

My guess as to why titanium isn't used for wheels is the high cost of the raw material and the difficulty in manufacturing. There are some intriguing benefits to titanium, such as a higher fatigue life than aluminum and a low elastic modulus which means it would offer a smoother/quieter ride than aluminum because of a natural damping effect.

Desmo

 

So would there be weight dissipation advantages too?

 

actually, wt:strength ratio favors Aluminum. The problem with aluminum is that in some applications, it isn't safe, as the materials yield point comes on much faster than Ti (which means it is very brittle, relatively speaking), while Ti is more flexible and will bend a fair amount before it breaks.

 

Another interesting material property to consider is Elastic Modulus/Density (stiffness/density) which is essentially the same for most metals, including Al and Ti. This ratio doesn't increase much until you start using composites.



P.S. A materials yield point is when it begins to deform plastically (i.e. permanently). Usually bad for wheels. A low yield point does not necessarily make a material brittle.

 

good point, I shouldn't have made it sound like they are related. GOod point about mentioning "plasticity" (VS elasticity) I was going to metnion that too, but left it out.

 

In fact... it would be hard to beat aluminum for a good heatsink. Almost all electronic heatsinks are aluminum for that reason.

 

Didn't the Z06 use magnesium wheels for a year or so?

 

Silver is better Talk about bling bling!