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CARBON FIBER’S time has come. This is not only in aerospace and high-end sports like Formula 1, but in automotive uses where material costs are typically figured in pennies rather than dollars.
I talked about these high-strength materials a while back (http://wp.me/p2ETap-zZ). Today I give an update of the materials’ increasing maturity, based on several articles in Automotive News, including “Carbon Fiber Heats Up,” May 19, 2014. (See http://goo.gl/UJxgNF.)
Carbon fibers are 60 percent lighter than steel and are 30 percent lighter than aluminum. They can be woven into components that exhibit directional strength allowing optimized engineering.
BMW has been particularly aggressive in automotive use of carbon fiber. Its M3 coupe’s roof is of this material. Body elements of its newly introduced i3 electric vehicle and coming i8 hybrid exotic are carbon fiber.
A joint venture of BMW and SGL Automotive Carbon Fibers, in Moses Lake, Washinton, produces carbon fiber thread. This is then shipped to Germany and woven into textile sheets at a facility in Wackersdorf, about 100 miles north of BMW’s Munich headquarters. The sheets are subsequently molded and cured into automotive components.
Carbon fiber is energy-intensive in its production. But, like much of the Northwest, Moses Lake profits from inexpensive hydroelectric power. Electricity cost to the facility is around 4¢/kWh, versus three times that rate in much of the U.S. (and five times that in Germany).
BMW and SGL have already invested $100,000 in Moses Lake’s automotive carbon fiber. Another $200,000 is planned. The facility now produces 3000 tons of carbon fiber annually. Production is planned to double this summer; by the end of 2015, it’s projected to be 9000 tons/year. With increased volume, evidently, comes reduced cost.
Another cost savings at Moses Lake is in choosing the right carbon fiber for the application: Automotive use doesn’t call for the ultra-high strength of aerospace applications. Appropriate selection can reduce material cost by two-thirds.
Traditional cost of a material tells only part of the story. Automotive steel is around 50¢/lb. Aluminum is perhaps $1/lb. Today, carbon fiber is in the range of $10 – $15/lb., with a target of $5/lb. or less. For full analysis, though, the weights, strengths and fabrication costs of finished components should be considered as well.
A major automotive supplier, Magna International Inc., will be producing carbon fiber body panels for an unnamed automaker in the 2016 model year. Magna, North America’s largest automotive supplier, has linked with Japan’s Toray Industries, the world’s largest producer of carbon fiber.
One of its keys in lowering cost is in fiber technology. Magna is testing finer threads woven into bundles of 50,000 strands. Today’s conventional fibers are thicker, more costly to produce, and woven into bundles of 12,000 to 15,000 threads.
Another cost reduction comes in fabrication. Conventionally, components of resin/carbon-fiber are baked for hours in autoclaves. Instead, Magna uses a compression mold process at higher temperatures and pressures, even more precisely controlled than those in autoclaves. Such components can be cured in five to ten minutes; research goals are to lower this to two to three.
Basic research at Tennessee’s Oak Ridge National Laboratory may also lead to lower cost. Lignin, a cheap byproduct in paper production, could provide a less expensive alternative in producing carbon-fiber thread.
Carbon fibers will never be the least expensive of materials. But their manifold benefits are combining with reduced costs to broaden their applications. ds
© Dennis Simanaitis, SimanaitisSays.com, 2014