LOS ALAMOS, NM -- Big Three engineers and government scientists cooperatively working on the development of an 80-mpg (2.9L/100 km) "supercar" are gradually sifting through the myriad technologies under their scrutiny as they push ahead to "lock in" the design and production parameters for the supercar project.
The first broad focus for the Partnership for a New Generation of Vehicles (PNGV) researchers: analyzing and developing the advanced manufacturing materials and processes that production of a family-sized 80-mpg vehicle will require.
The U.S. Big Three automakers, through their technology development consortium, USCAR (the United States Council for Automotive Research), announced two years ago their intent to cooperate with 11 government agencies to create PNGV, whose singular goal is to build by 2005 a production prototype high-mileage midsize passenger car capable of delivering 80-plus mpg, with performance comparable to today's mainstream family sedans.
PNGV engineers recognize that such drastic improvement in fuel economy will require vehicles to be much lighter than those currently in production. However, producing such vehicles, in the words of one PNGV manufacturing engineer, "will likely require a fundamental shift to new materials and new manufacturing methods. That's why evaluating the manufacturing ramifications (to producing PNGV-type vehicles) is the first major aspect we're studying. A major restructuring of production methods and the materials we use has huge impact on the entire industry."
That restructuring could prove costly. PNGV estimates that the Big Three currently have more than $115 billion invested in production plants and equipment; associated suppliers have upwards of $50 billion invested in existing infrastructure. Sixty percent of vehicle production cost is in manufacturing, and producing an affordable supercar hinges on adopting a strategy that combines the most efficient employment of existing production infrastructure with new manufacturing developments.
PNGV officials and engineers showcased for journalists a few of the advanced manufacturing technologies researchers are evaluating at the National Laboratories here and the Sandia National Laboratories in Albuquerque. Some are, by the scientists' own admission, long from presenting any near-term potential. But other technology under development here is directly related to PNGV's so-called "Sweet 16," a select group of manufacturing processes the coalition believes is critical to creating an affordable supercar (see chart).
A sampling of the advanced production methods PNGV has under development:
* High-voltage "induction" hardening of metal parts. By introducing high heat in the form of electric energy, the part becomes extremely hot on the exterior while the interior remains cool. It is then quenched with water, resulting in a highly controlled degree of microfinish to the part.
Sandia's scientists currently work with engineers atCorp.'s Saginaw unit in a pilot program. The new process is said to eliminate the variability in traditional hardening processes and is 40% more energy efficient. Because the process is controlled in "real time," researchers say the need for individual part sampling is significantly reduced.
* Thermal spray coating of cylinder bores for aluminum engines. Layers of wear-resistant material (a mix of aluminum and bronze, for example) are sprayed on the bores at high velocity; the speed of the particles and the grainy surface of the bore ensure proper binding.
Engineers say this process, which is under way in pilot programs at each of the Big Three automakers, perhaps could also be used for piston rings, fuel-injector nozzles and other engine components. But for cylinder bores, the advantage is in the elimination of heavy iron sleeves or the need to construct the block with expensive aluminum alloys.
* Computer-assisted laser welding of aluminum. Laser welding is nothing new for joining steel, but because of aluminum's unique reflective properties, welding it has, to now, proven difficult. New high-energy, extremely precise lasers are being developed that will join aluminum pieces of varying thicknesses, meaning tailored aluminum blanks can be produced.
"You can get to very high weld speeds with laser welding," says one project engineer. He adds that the new technique under study employs a guiding laser in addition to the laser that actually creates the weld. By keeping the weld "gap" as narrow as possible, the reflectivity of aluminum is minimized.
Speculation ran rampant after last fall's Republican "takeover" of Congress that PNGV's funding could be sharply curtailed, or even eliminated. But PNGV officials express confidence that the supercar program remains in good financial shape.
Robert M. Chapman, chairman of the PNGV task force at the U.S. Dept. of Commerce Technology Admin., says although requested increases in PNGV's budget apparently are out of the question, he believes Congress will appropriate funds to keep the PNGV budget at or near this year's $270 million level.
Process and equipment simulation Springback predictability Open architecture Feature-based modeling Flexible machine and assembly Low-volume stamping Agile part fixturing Rapid tool and die fabrication Dry machining (aluminum) Leak testing and detection Optimizing torque tools High-volume cutting tools development Aluminum joining and welding Aluminum die casting Paint processing Welder controllers
The Sweet 16 are manufacturing technologies that PNGV deems critical to producing an affordable supercar.