Oak Ridge National Laboratory

Carbon Fiber and Composites

Carbon fiber is a strong, stiff, lightweight enabling material for improved performance in many applications. However, use of carbon fiber composites in cost-sensitive, high-volume industrial applications such as automobiles, wind energy, oil and gas, and infrastructure is limited because of today’s relatively high price. Current methods for manufacturing carbon fiber and carbon-fiber-reinforced composite structures tend to be slow and energy intensive. New, innovative manufacturing processes for low-cost precursor development and conversion technologies hold the key to reducing carbon fiber cost for energy applications. Similarly, innovative performance-focused materials and processes can potentially drive significant performance improvements for national security applications.

Advanced CF Conversion Technologies

Equipment and Capabilities

  • Lab-scale and pilot-scale spinning and heat treatment
  • Bi-component filament extruder
  • Dynamic Scanning Calorimetry
  • Thermogravimetric Analysis
  • Thermomechanical Analysis
  • Electrical resistivity of fibers
  • Ultrapycnometer density measurement
  • Dynamic Contact Angle measurement
  • Viscometers
  • BET (surface area measurement)
  • Mass Spectrometry
  • High performance high pressure microbalance
  • Large volume high-pressure gravimetric adsorption cell
  • Dual symmetrical thermogravimetric analysis coupled with mass spectrometer
  • Advanced rheometer expansion system
  • Electrochemical station
  • Automatic micro-titration system

ORNL is presently leading a major DOE initiative to develop disruptive technologies for producing low cost carbon fiber. Major focal areas are (i) alternative precursors, (ii) advanced, energy efficient processes, and (iii) scaling for technology transition. ORNL processing capabilities range from single filament to tens of tons annually, with characterization capabilities at length scales from sub-Angstrom to approximately one meter.

The primary focus of ORNL’s carbon fiber research is disruptive cost reduction for industrial grade carbon fibers, with modest performance penalty being acceptable. This program includes efforts aimed at significant cost reduction for the highest performing standard modulus carbon fibers, with little or no performance penalty. Finally ORNL’s carbon fiber program does include a high performance element in which new performance levels are sought with cost being a secondary factor.

Carbon Fiber Scale-Up

Oxidized fibers are converted into carbon fiber

Equipment and Capabilities

The CFTF, with its 390-ft. long processing line, is capable of custom unit operation configuration and has a capacity of up to 25 tons per year, allowing industry to validate conversion of their carbon fiber precursors at semi-production scale.

Melt-Spun Precursor Fiber Production

  • Rated capacity 65 tonnes/year based on polyolefins
  • Spins most melt-stable polymers, specifically including polyolefins and lignin; upgradable for melt-spun PAN
  • Tow production up to 2,000 m/min winding speed
  • Melt-blown web production up to 300 mm width, packaged or direct-fed to carbon fiber line; upgradable to include spun-bond
  • Homo- and bicomponent filament production; upgradable to tricomponent
  • 450°C temperature rating
  • Corrosion-resistant wetted surfaces
  • Extrusion screw L/D 30:1; upgradable to 40:1 

Carbon Fiber Production

  • Rated capacity 25 tonnes/year based on 24k PAN tows
  • Designed for PAN, polyolefins, lignin, and pitch precursors; 
upgradable for rayon and high-modulus carbon fibers
  • Designed for 3k to 80k tows and web up to 300 mm wide x 12.7 mm loft
  • Oxidation temperature up to 400°C with airflow configurable to be parallel, cross, or downflow
  • Low-temperature carbonization up to 1000°C with capability to produce structural or micro/nanoporous fibers
  • High-temperature carbonization to 2000°C
  • Post treatment system designed for compatibilizing fibers with performance or commodity resins

The Carbon Fiber Technology Facility (CFTF) serves as a national test-bed for government and commercial partners to scale-up emerging carbon fiber technology. As part of ORNL’s DOE-funded Manufacturing Demonstration Facility, the CFTF serves as a hub for public–private partnerships in the emerging national network for innovations in manufacturing. One such partnership consisting of more than fifty companies, the Oak Ridge Carbon Fiber Composites Consortium has formed in Oak Ridge, Tennessee. The mission of the Consortium is to forge industry–government collaborations to accelerate the development and deployment of lower-cost carbon fiber materials and processes and create a new generation of strong, lightweight composite materials that will improve America’s competitiveness.

Carbon Fiber Composites

Carbon composite technology showcased at dedication of DOE's Carbon Fiber Technology Facility

  • Computing platforms and analysis codes for micromechanics, laminate theory, and ply-by-ply stress analysis
  • 15 kg/min robotic preformer750-ton intelligent leveling prress with 500deg F heating system
  • 4-axis computer-controlled filament winder with 30in dia X 12ft capability
  • Laboratory autoclave and presses
  • Resin transfer molding systems
  • SRIM system
  • Capillary rheometer

Facilities and process equipment combine the flexibility to support development of new manufacturing concepts with capacity to produce full-scale demonstration components. New materials are typically benchmarked in conventional thermal processes. Process development is focused on advanced processing techniques such as electron-beam and microwave curing, robotic preforming, high performance filament winding, etc.