If the BMW i3 city car rolls out of the company’s Leipzig plant later this coming year, it can represent the initial carbon-fiber car that will be created in any quantity-about 40,000 vehicles a year at full output. The lightweight but sturdy nonmetallic structure of the new commuter car, the consequence of BMW’s joint venture with SGL Technologies in Wiesbaden, will mark a milestone in the growth of carbon-fiber-reinforced plastic (CFRP) materials, that have traditionally been very expensive to be used in automotive mass production.
CFRPs are engineered materials that happen to be fabricated by embedding webs of carbon fiber inside molded polymer resins. The fibers bolster the physical properties of your plastic matrix component likewise which a skeleton of steel rebar strengthens a poured-concrete structure.
While the i3 electric vehicle (EV) won’t exactly come cheap-estimates run from $40,000 to $50,000-BMW reportedly claims that forthcoming improvements in the production process during the next 3 to 5 years should cut carbon composite costs enough to complement the ones from aluminum chassis, which still command limited over standard steel car frames.
CFRP structures weigh half that relating to steel counterparts as well as a third less than aluminum ones. Add the inherent corrosion resistance of composites and the ability of purpose-designed, molded components to cut parts counts by way of a factor of 10, and also the attract automakers is obvious. But despite the key benefits of using CFRPs, composites cost far more than metals, even making it possible for their lighter in weight. Our prime prices have thus far limited their use to high-performance vehicles for example jet fighters, spacecraft, racecars, racing yachts, exotic sports cars, and notably, the newest Airbus and Boeing airliners.
Whereas steel goes for between $.80 and $1/kg, and aluminum costs between $2.40 and $2.60/kg, polyester and epoxy resins range between $5 to $15/kg and the reinforcing fiber costs one more $2 to $30/kg, according to quality. Make it possible for cars to get rid of the United states government’s fast-approaching 54.5-mpg average fuel-economy bar, automakers and their suppliers are striving to generate methods to produce affordable carbon-fiber cars around the mass-scale.
But adapting structural composites to low-cost mass production has long been a technical and manufacturing challenge, said Ross Kozarsky, Senior Analyst at Lux Research, an independent research and consulting firm that is focused on emerging technologies.
Kozarsky follows composite materials and led a study team that this past year assessed CFRP manufacturing costs and identified potential innovations in each step of your complex process.
“Our methodology would be to follow, through visits and interviews, the entire value chain through the tow, yarn, and grade level onwards, examining the supplier structure and also the general market costs,” he explained. The Lux team then created a cost model that mixes material, capital expenditure, infrastructure, labor, and utility consideration as well as the chances for cost reductions.
Although the sporting goods, military, and aerospace industries have traditionally developed and first applied composite materials, the pre-eminence of those segments when it comes to sales is ending, Kozarsky said. The wind-turbine business will deal with aerospace for the top market as larger, more-efficient offshore wind-power installations are built.
“It’s cheaper to utilize bigger turbine blades, which can basically be made using carbon-fiber materials,” he noted.
The Lux report predicted the global market for CFRPs will a lot more than double from $14.6 billion in 2012 to $36 billion in 2020, as innovative new production technologies lower carbon-fiber costs-the key cost-driver. During the same period, requirement for carbon fiber is anticipated to increase fourfold from your current 27,000 million ton (24,500 million t) to 110,000 million ton (99,800 million t).
Major suppliers of carbon fiber include Toray, Zoltek, Toho, Mitsubishi, Hexcel, Formosa Plastics, SGL Carbon, Cytec, AKSA, Hyosung, SABIC, and more than a dozen smaller Chinese companies.
“A large amount of folks are talking about automotive uses now, which happens to be totally on the opposite end in the spectrum from aerospace applications, since it has a higher volume and more cost-sensitivity,” Kozarsky said. After a slow start, the car industry will love the second-largest average industry segment improvement through the decade, growing in a 17% clip, in line with the Lux forecast.
The Lux analysis shows that CFRP technology remains expensive due to the fact of high material costs-specially the carbon-fiber reinforcements-along with slow manufacturing throughput, he reported.
“The industry has reached an appealing precipice,” he said, wherein industrial ingenuity will vie using the traditional technical challenges to try and match the new demand while lowering costs and speeding production cycle times.
The very best-performing carbon fibers-the higher grades used in defense and aerospace applications-begin as what exactly is called PAN (polyacrylonitrile) precursors. As a result of difficulty of your manufacturing process, PAN fibers cost about $21.5/kg, in accordance with Kozarsky, who explained that makers subject the PAN to several thermal treatments wherein the material is polymerized and carbonized because it is stretched. The resulting “conversion” leaves the filaments oriented along the length of the fiber allow it the ideal strength and toughness. Various post-processing stages and the surface-acting additives help ensure durability and “handleability.
Kozarsky singled out a commercial/government R&D collaboration in the new Carbon Fiber Technology Facility at Oak Ridge National Laboratory (ORNL), that has been funded with $35 million in U.S. Department of Energy money as one of the more promising efforts to lessen fiber costs. Section of the project would be to identify cheaper precursor materials which can be processed into good-quality fibers (see “Oak Ridge collaborates for cheaper carbon fiber,”. The blueprint is to test various types of potential low-cost fiber precursors for example the cheaper polymers, inexpensive textiles, some produced from low-quality plant fibers or renewable natural fibers like wood lignin, and melt-span PAN.
Near term the Lux team expects the task that ORNL has been doing with Portuguese acrylic-fiber maker FISIP (majority belonging to SGL) on textile-grade PAN to obtain costs at the pilot-line scale of $19.3/kg in 2013. Although significant, it could be merely a modest reduction when compared to the 50% required for penetration in high-volume auto applications.
One of the major limitations of PAN, he stated, is “at best 2 kg of PAN yields 1 kg of carbon fiber, which gives a conversion efficiency of just 50%.” Dow Chemical is investigating dexnpky63 polyolefins-polyethylene, polypropylene-because the feedstock simply because they could offer potential conversion efficiencies of 70% to 75%. If mechanical performance targets might be met, pilot-line costs of $13.8/kg may be achieved by 2017, stated the report.
The Oak Ridge group, Kozarsky said, can also be taking care of novel microwave-assisted plasma carbonization techniques that may produce useful, uniform fiber properties. And ORNL’s nonthermal plasma oxidation process has been shown to have the potential to stabilize and cross-link the precursor materials rapidly and efficiently.
Polyolefin-precursor carbon fiber, put together with these kinds of alternative thermal-treatment mechanisms, should reduce costs to sub $11/kg at pilot-line scale in 2017, he noted. Kozarsky added that “there’s a lot of curiosity about increasing the resin matrix as well,” with research concentrating on using thermoplastics rather than the existing thermosets and producing higher-toughness, faster-processing polymers.