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Lignin by-products from biorefineries has the potential to provide a low-cost alternative to petroleum-based precursors to manufacture carbon fiber, which can be combined with a binding matrix to produce a structural material with much greater specific strength and specific stiffness than conventional materials such as steel and aluminum. The market for carbon fiber is universally projected to grow exponentially to fill the needs of clean energy technologies such as wind turbines and to improve the fuel economies in vehicles through lightweighting. In addition to cellulosic biofuel production, lignin-based carbon fiber production coupled with biorefineries may provide $2,400 to $3,600 added value dry Mg−1 of biomass for vehicle applications. Compared to producing ethanol alone, the addition of lignin-derived carbon fiber could increase biorefinery gross revenue by 30% to 300%.

The crush performance of lightweight composite automotive structures varies significantly between static and dynamic test conditions. This paper discusses the development of a new dynamic testing facility that can be used to characterize crash performance at high loads and constant speed. Previous research results from the Energy Management Working Group (EMWG) of the Automotive Composites Consortium (ACC) showed that the static crush resistance of composite tubes can be significantly greater than dynamic crush results at speeds greater than 2 m/s. The new testing facility will provide the unique capability to crush structures at high loads in the intermediate velocity range. A novel machine control system was designed and projections of the machine performance indicate its compliance with the desired test tolerances. The test machine will be part of a national user facility at the Oak Ridge National Laboratory (ORNL) and will be available for use in the summer of 2002.

The Automotive Composites Consortium has initiated the third of a series of focal projects, which is a multi-year program to develop a design and manufacturing strategy for a composite intensive body-in-white (BIW) with aggressive mass reduction, manufacturing cycle time, and cost parity targets. Specifically, the BIW is to exhibit 60% minimum mass savings over the conventional steel baseline, contain the same package space as the baseline, meet or exceed the structural performance, and have cost parity to the baseline in volumes exceeding 100,000 per annum. The Department of Energy's Office of Advanced Automotive Technology provided most of the funding for this project. A design study was undertaken to evaluate whether the mass savings are feasible - utilizing carbon-fiber composites - without sacrificing structural performance. The design was conducted with consideration to cost-effective composites manufacturing processes that are under development.

Several standard methods exist for testing composites, metals and plastics in Mode I fracture. However, these standard test methods have limitations that disqualify them as candidates for testing certain automotive materials. In order to conduct successful fracture toughness tests with these automotive materials, a modified double cantilever beam testing geometry and associated new procedure have been developed. Both the test procedure and the data analysis have been fully documented in a draft standard. Representative SRIM composite, e-coat steel and epoxy were selected to develop and validate the testing procedure.

The desire to use lightweight materials to reduce weight in automotive structures has resulted in the need to develop new fastening technologies. The use of welds, screw type fasteners, and bolted joints traditionally used in solely metallic structures may be inappropriate for many polymeric and composite structural components. With this in mind, an obvious alternative fastening technology would include adhesive joints. To make use of adhesive joints, and ultimately the wide class of lightweight materials, it is necessary to understand all aspects of this attachment technology, including the adhesives that comprise the joint. This work will focus on the mechanical response of a candidate automotive adhesive. Specifically, predictive relationships between creep and fatigue response will be developed and verified through comparison with experimental results.