Alcoa developing lighter wheels for increased efficiency
Heavy steel wheels are relatively rare in showrooms these days -- it seems they are heading the way of bias-ply tires. Most new cars are delivered with cast aluminum wheels. While cast wheels weigh less than comparative steel wheels, they are still manufactured with thick castings and solid spokes (forged aluminum wheels, both lighter and stronger, are generally more expensive and as such, fitted largely to performance vehicles). Alcoa Wheel & Transportation Products, one of the world's largest aluminum suppliers, is determined to reinvent the wheel in an effort to save fuel and lower emissions. The company is tackling this issue by designing wheels manufactured with higher strength aircraft-quality aluminum. The alloy is 20 percent stronger than the current wheel material, so wheels can be made thinner and with hollow spokes.
Alcoa recently displayed two 20-inch wheels for comparison: A Chrysler OEM aluminum wheel weighed 35.5 pounds, while the Alcoa alloy wheel weighed just 27.7 pounds. The benefits are obvious, and Alcoa is quick to point out that the weight savings are a simple bolt-on solution -- they don't require expensive engineering at the design level to seek weight-savings. Educating the public that lightweight wheels aren't just for high-performance vehicles, the aluminum manufacturer says that the reduced unsprung mass benefits hybrid and electric vehicles by extending their range and increasing their efficiency... and lest we forget, Alcoa is the OEM wheel supplier to the upcoming Chevrolet Volt.
[Source: Automotive News, subs. req'd]
Reader Comments (Page 1 of 1)
Richard 6:37PM (3/17/2009)
Yes. But how will they fare on post-winter roadways in places like Detroit, Chicago and Boston. Some of the potholes I have seen are true wheel breakers!
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Chris 6:52PM (3/17/2009)
Pfft.... aluminum, how quaint! How about some CARBON FIBRE wheels?
http://www.wheelenhancement.com/index.php?t=WheelDetail&id=212
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xtasi 7:00PM (3/17/2009)
Most people don't care how sausage is made. Just make them standard equipment. Boosts MPG. People that care will notice that lower unsprung weight increases acceleration, reduces braking distance.
@Chris. Those wheels are awesome. No price listed, and the cars being demo on lets me know that I can't afford them.
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Toy Yoda 2:48PM (3/18/2009)
Last time I checked, these dymag CF rims are at least $5k a piece. So you will be spending at least $20k to put them on your car. So they aren't realistic alternatives, not by any means.
And even if you had the money, you won't be able to take your hot date out with your hot car with CF rims without constantly worrying about the your rims being stolen. What a great lure for any thief to make $20k in 5-10 minutes worth of work.
Max 8:06PM (3/17/2009)
Website doesn't even provide any passenger car applications, only for trucks and such. I know they made a custom set for Jay Leno. Wonder what it'll take for them to start production on a wheels for passenger cars (non-truck).
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Mister Bean 7:50PM (3/17/2009)
Even more weight could be saved by manufacturers not using such ridiculously oversized wheels. Unless you can't clear the brakes, there's really no reason to go larger.
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imirk 7:52PM (3/17/2009)
+1
a 14" steelie weighs ~20lbs and gives a better(more compliant) ride
apearlman 8:58PM (3/17/2009)
Agreed on the value of small steel wheels. Much more durable than alloys, and also less likely to develop slow leaks due to bad beads.
superman211 10:12PM (3/17/2009)
So that your car does not look like a POS hyundia!
pio!pio! 1:00AM (3/18/2009)
thats heavy for a 14" wheel! My old 15" forged aluminum wheel was 9 pounds and strong as hell.
Richard 10:37AM (3/18/2009)
Either way, a 14 or 15" wheel with - what - 80 series tires and your car handles like a Camaro - on ice. But the ride will be nice!
tankd0g 12:42AM (3/18/2009)
So now we can add 20 pounds of chrome instead of just 15!
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jeff 2:13AM (3/18/2009)
Forging results in wheels that have significantly less mass than casting. I have 20" 3 piece forged wheels on my car and even with 305 tires on 20x11 wheels they are impressively light.
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Imee 8:00AM (3/18/2009)
This is pretty interesting, actually. I mean, if an alloy wheel can increase efficiency of a car, I'm all for it. Add that to green fuel and a sweet-looking ride, then my dreamcar is there!
Imee
http://www.cashgrants.org
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CraigD 11:42AM (3/18/2009)
I think the point of these aluminum wheels is to showcase the opportunity available by making small process tweaks.
Forged wheels are much more expensive than cast wheels because of very expensive tooling (high capital investment). I can't imagine this would make much difference if they were standard equipment on high-volume cars, but it's enough to scare off mainstream manufacturers. Carbon Fiber wheels use expensive material and monumentally expensive and difficult (near impossible at even today's "mass" production volumes) processes to achieve unproven reliability.
Forged wheels are stronger because the manufacturing process aligns the material's microstructure in the direction of stress and work hardens the material simultaneously. Casting cannot take advantage of this, plus requires certain alloy properties conducive to mold flow that forging does not require. It seems Alcoa has managed to mold an alloy with improved properties over typical casting alloys, and that's the real story.
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