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Is Carbon Fiber Going Mainstream?
cartechboy (2660665) writes "To date, carbon fiber has been expensive and presents different production challenges than traditional steel and aluminum. But now it seems as if the advanced material is about to become truly mainstream--BMW has announced it plans to triple carbon fiber reinforced plastic output at its Moses Lake facility in Washington state. Currently, the SGL Group plant, a joint venture partner of BMW Group, has the production capacity for about 3,000 tons of carbon fiber per annum. Two productions lines are currently going with the output dedicated to BMW's i3 and i8 plug-in vehicles. SGL is already working on a third and fourth production line which would double production to 6,000 tons per year, but a fifth and sixth are on the way, set to triple capacity to 9,000 tons every year. This extra output won't be reserved exclusively for BMW's i range. Several future BMW models will make use of the lightweight material. Now the only question is how long before carbon fiber vehicle construction becomes as common as aluminum?"
Carbon fiber is the least recyclable material ever.
No doubt they will claim they are recycling it in some unholy process, but it would be far more environmentally friendly to produce the raw stock.
Now steel and aluminum are highly recyclable. And cleanly too.
BMW has already been putting CF into weight-sensitive areas of the car, like the roof panels on certain models. Up high is one of the worst places to carry weight from a vehicle dynamics perspective; it makes nearly every aspect of vehicle handling worse.
One practical difficulty of CF for general automotive use is that it's not really repairable.
Of course, modern autobody repair is often about replacing affected panels with pristine replacements (either new or from junk yard cars), as opposed to trying to repair an existing panel. So, in that sense, CF might be a fine choice, as the lack of reparability is in practice a non-issue.
BMW is already gluing cars together -- for almost 10 years they have been building the front clip on certain models out of aluminum, and in effect gluing it to the remainder of the unibody, which is conventional steel.
Also, BMW has been designing recyclability into its cars also for at least 15 years. I seem to recall that the E46 3 series was something like 90% recoverable.
I don't expect they would turn away from their recyclability commitment, so they must have a plausible plan for how they would like to apply it to CF parts.
My opinions are my own, and do not necessarily represent those of my employer.
Once I learned about carbon fiber thermoplastics, I realized that carbon fiber would be amenable to mass production. The idea is that you lay down the fibers using robotic technology. Then you encase the fiber in a plastic resin that becomes soft at high temperatures. Now you have made a flat carbon fiber sheet similar to sheet steel. Finally you use a hot press that presses the sheet into nearly any shape desired...ie. car parts. This is similar to how we form steel into car body parts. This processes is highly suitable for mass production. So yes, carbon fiber is becoming mainstream.
This and no other is the root from which a tyrant springs; when first he appears as a protector - Plato (423 to 327 BC)
No, half the weight does not mean half the fuel usage. Windage losses do not scale with weight, as passenger size does not scale with vehicle weight. Highway driving in particular is dominated by windage losses (after engine Carnot efficiencies of course). A half weight vehicle will see only modest highway MPG improvements not double, and will not be able to scale the engine size down by fully half either due to the horsepower requirements for reasonable highway performance not scaling down by half. So sadly, a half weight frame and body does not let you continue to scale the rest of the weighty vehicle down by half, which does not result in a doubling of MPG or range.