Aluminum usage in automobiles and light trucks has been climbing steadily. Evenmore important, auto manufacturers are beginning to see aluminum the wayaircraft manufacturers do – as the basic structural material for their vehicles. Increasingly, in the case of carmakers, that thinking begins with an aluminumbody structure such as the spaceframe. It’s a new and potentially powerfultrend.
As recently as 1990, there were no aluminum-structured passenger cars inproduction anywhere in the world. The closest thing was the HMMV (Hummer), atthat time strictly a military vehicle. As of 1997, there were sevenaluminum-structured passenger cars in production. For three of them – Audi A8,Plymouth Prowler, and GM EV-1 – Alcoa has been the principal partner indesigning, engineering and manufacturing aluminum components, subassemblies, and- in the case of the Prowler – the frame itself.
And that’s just the beginning. A concept car with a modular spaceframe in technology reviews held for Ford andChrysler, Alcoa unveiled a vehicle concept embodying ideas for future cars andlight trucks. The design is based on a spaceframe structure comparable to thoseAlcoa has helped to develop for the Audi A8 and Plymouth Prowler. But in theconcept vehicle, the spaceframe is modular, a step toward using such structuresin a broad range of future vehicles. By changing modules, a carmaker couldproduce a sedan, a sport utility vehicle, and a pickup truck, all from a singleproduction platform. New programs with Daimler-Benz and Chrysler Alcoa isproducing the front energy management structure for the new Mercedes-BenzA-class car (above) now selling in Europe.
This 11-piece structure was designedby Alcoa and is robotically assembled at Alcoa’s plant in Soest, Germany. Production volume is expected to reach 1,000 units per day. For Chrysler, analuminum rear crossmember designed and manufactured by Alcoa improves thehandling and noise-vibration-harshness performance of the all-new 1998 DodgeIntrepid and Chrysler Concorde as well as the 1999 Chrysler LHS and 300M models. AAS will manufacture 270,000 units per year at its Northwood, Ohio plant.
Something new around the windshield. A key advance incorporated in the 1997Corvette is a first-of-its-kind windshield surround developed in a design andengineering collaboration of General Motors and Alcoa. An effective combinationof aluminum cast and extruded products makes this an extremely stiff structure,helping the new Corvette to earn excellent reviews for its stiffness andsuperior handling. Northwood will produce 25,000 windshield surrounds annually.
. Design tools to aid in product development New guidelines for use in designingautomotive components have been installed at AAS operations in Esslingen,Germany; Southfield, Mich; and Alcoa Technical Center (ATC) near Pittsburgh. Developed by AAS and ATC, the guidelines will assist automotive engineers inevaluating product design and fabrication options. Objectives: Improve designquality and cut development time by 30%.
Audi A8 is picked as a technologicalwinner In December, the Audi A8 was named one of the top 25 Winning Technologiesby Industry Week (IW) magazine in the U. S. The editors report: “The 1997Audi A8 with its aluminum spaceframe body technology indicates what is possiblewhen the status quo in materials is challenged in automotive design. The luxurysedan delivers a new standard in weight savings, structural integrity, safety,performance and comfort. ” IW traces the origins of the Audi spaceframe to”an early 1980s R&D initiative that became a joint-venture with Alcoa.
The spaceframe took 10 years to develop,” the editors note, “and isthe result of 40 new patents, seven new aircraft-grade aluminum alloys, andextensive design analysis via supercomputers. ” Alloy A substance withmetallic properties, composed of two or more chemical elements of which at leastone is a metal. More specifically, aluminum plus one or more other elements,produced to have certain specific, desirable characteristics. Alumina Aluminumoxide produced from bauxite by an intricate chemical process. It is a whitepowdery material that looks like granulated sugar.
Alumina is an intermediatestep in the production of aluminum from bauxite and is also a valuable chemicalon its own. Aluminum Spaceframe An integrated structure of aluminum castings andextruded parts that forms the primary body frame of a new generation ofautomobiles. Bauxite An ore from which alumina is extracted and from whichaluminum is eventually smelted. Bauxite usually contains at least 45% alumina. About four pounds of bauxite are required to produce one pound of aluminum.
Brazing Joining metals by flowing a thin layer of molten, nonferrous fillermetal into the space between them. . Crossmember Component of a vehiclestructure that spans the structure, joining two sides together. Engineeredproduct .