Carbon fiber. Stronger than steel. Beauty and function. Colorless rayon or polyacrylonite fibers are pulled over hundreds of reels 200m long and baked at temperatures as high as 1,400 Celsius (2,550 Fahrenheit). Only carbon atoms remain, neatly arranged and now black, 1/10th the width of human hair.
50,000 of these are bundled into a thin thread, capable of lifting a tonne of weight. The threads are woven into mats, cut and placed in molds, put in vacuum, immersed in resin and cured by heating. Within minutes, they harden to create body parts for a car, 5x stronger than steel, 2x more rigid but 60% less in weight. That alone could reduce a car’s fuel consumption by 30 percent and cut greenhouse gas and other emissions by 10 to 20 percent [source: Oak Ridge National Laboratory].
With their swoopy carbon fiber bodies, the BMW i3 city car and sportier i8 look like the auto show concepts that never get beyond auto shows. In fact, they are just two years from production.
Read more: http://www.huffingtonpost.com/2011/11/19/bmw-carbon-fiber-car_n_1102774.html
http://www.extremetech.com/extreme/91600-bmwβs-dazzling-i-brand-why-they-opted-for-a-carbon-fiber-chevy-volt-not-a-nissan-leaf
Hat tip to Shah Auckburaully , for the inspiration.
Bavarian Motor Works
Terry Hallett , yeah, I’ma fan π
Jaydeep Sanyal , which concept? Carbon fiber cars? They are already in use in race cars and were adopted early by Rolls Royce, but with problems. The point is that they are being mainstreamed now.
Yeah, sure..in everything from structural engineering to hockey sticks! π
That’s why we have Wikipedia. http://en.wikipedia.org/wiki/Carbon-fiber-reinforced_polymer
Tony Bryson , the hold up so far was that carbon fiber is pricier than steel. But BMW has just purchased a significant stake in SGL Carbon and set up a joint factory in Washington State. This is probably the reason they can now mass produce the i series of cars. And hey, they look good too!
Very cool.
What do you mean? Dangerous for those who fabricate?
I did a quick check and it does seem that carbon nanotubes look like asbestos fibers and could potentially be as toxic. However, this article suggests that they are not as bad when inhaled because “They are quite highly charged and stick together, so they don’t seem to get airborne easily.”
http://www.newscientist.com/article/dn13946-nanotubes-toxic-effects-similar-to-asbestos.html
In my humble bicyclist experience, carbon absolutely increases velocity. However, it also provides a significantly “bumpier” ride. Rather than the old fashioned aluminum bikes absorbing some of the shock when a bicyclist hits a bump, the bump goes more directly to the rider. I’m curious to see if, at the automobile level, there’s a similar “bumpier” issue, and if so, how the manufacturers compensate for it. In other words, the very way the car “rides” or “feels” might change.
Oh – in addition to the above-mention hockey sticks, a fellow bicyclist told me that there are actually carbon fiber bicyclist shoes somewheres out there. Very expensive.
David Anthony , I’m no materials scientist, so perhaps you can take a look at this link that seems to address the issue of vibration damping. http://carbonrev.com/carbon_fiber_facts.html
With regard to carbon fiber wheels (not chassis), the article concludes, “Vibration and shock damping are two important factors that affect ride and handling. However, they are two of the least understood subjects in materials science. There are so many variables involved – including how atoms in a material absorb and dissipate vibration energy, how the structure is built, what type of paint and plating are applied – that it is hard to predict how a structure will react to vibration input. Composite’s vibration damping is far superior to any metal, which is why it is the preferred material for race car springs and high performance airplanes. The smooth ride quality is one of the first things people notice about carbon fiber wheels.”
Seems to me that the advantage may be based on cleverness of design: “Unlike isotropic metals, composites are anisotropic – their strength and stiffness is only realized along the axis of the fibers which can be arranged in any desired pattern. Thus, to absorb the variable stresses seen by wheels on road, composite designs can use multiple layers with different fiber angles for each. This puts strength only where it is needed while minimizing weight.”
I would trust a humble bicyclist’s personal experience, however, to some random internet article!
On another note, I failed to mention that the Boeing Dreamliner 787 is 50% composite carbon fiber as opposed to previous models that were all aluminum. “The much-delayed Boeing Dreamliner 787 has a range of 10,000 miles, is far quieter than ordinary jets, and is constructed using a ‘moulding’ process that has eliminated 1,500 aluminum sheets and 50,000 fasteners. It’s also three years late – and has cost a reported $32 billion.” http://www.dailymail.co.uk/sciencetech/article-2041863/Boeing-787-Dreamliner-reality-carbon-fibre-plane-delivered-Japan.html
When, oh when, will writers stop using Width Of A Human Hair as a unit? It varies by a factor of sixty. Rather worse than using the king’s foot.
Haha, Camille Goudeseune , …now I know, thanks to amazing Googlers. How about this…single walled carbon nanotubes are typically 1 nm in width. The thinnest carbon nanotube has a diameter of 3 Γ .
Better? π
Tony Bryson, I suspect that a careful analysis of the numbers will reveal some sloppy claims! According to Wiki, a hair is about 10 micrometers (10^-6m). A nanometer is 10^-9 m. Angstroms are just a fancy way of saying 10^-8m. Now, we’re smarter, right? Right????
Tony Bryson , in the end, this was all just an excuse for us to look at shiny swoopy cars π
Rajini Rao
So with the new carbon fiber car the cost would be (10^10)^-10 ?
Tom Lee , the 2014 i3 will start around 30K and the beauteous i8 at 170K. Which is pretty much the same as 10^ for practical purposes. Let me check my piggy bank…
Quite hefty for the high end model. Still gonna carry me from A to B. If the body can withstand large impact and the driver’s chance for injury or death is reduced five folds than I may want to sell my vacation condo to get one. π
Tom Lee , driving a Beemer is like living in a vacation villa π
Rajini Rao Thanks for the link. Very interesting – ” The smooth ride quality is one of the first things people notice about carbon fiber wheels.”
On a non-vibration damping note (!), I’ll say this: A couple of years ago, I stopped by my regular bike shop to purchase a new bicycle. Just for fun, I checked out a carbon fiber bicycle- the frame, the fork, every piece possible was of carbon fiber. It was amazingly light. I could pick it up with my little finger and still not really notice. The folks running the bike shop suggested that I take it for a ride, telling me that I’d love the way the bike rode…and I was tempted…until I saw the price tag. It retailed for over $10,000!
After 20 years of waiting for affordable carbon fiber cloth I’ve come to the conclusion that the price will only come down when it’s no longer viable to sell “high” to weapons manufacturers and the related military aerospace industry. There isn’t enough competition for the product and manufacturers aren’t interested in opening or are unable to open up new markets.
Richard Healy , good point..perhaps now that BMW and rival Volkswagen are in competition to acquire stakes in SGL carbon, there seems to be a “broad trend in the auto industry in recent years to enter cooperation agreements and alliances to share costs for developing new vehicles”. Hopefully, this signals a change. See: http://online.wsj.com/article/BT-CO-20111118-710066.html