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A D V A N C E D M A T E R I A L S & P R O C E S S E S | A P R I L 2 0 1 9 2 1 The public reveal of the embodi- ment of the concept took place on De- cember 22, 1982, when BLT introduced the ECV3 prototype to the press. Not- withstanding its name, ECV3 was the second drivable version of Spen King’s energy conservation vehicles (ECVs). The first, ECV2, had been a rolling test bed for King’s concept of the powertrain of the future for a mass-production car—a highly efficient gasoline multi- valve, three-cylinder engine, featuring lean-burn technology and mated to a CVT transmission. ECV3 took all of these and installed them in a lightweight alu- minum structure under an aerodynam- ic thermoplastic skin (Fig. 2). ECV3 was developed entirely with- in BLT, precluding any alloy or coil pre- treatment developments. The team focused on demonstrating the concept of an aluminum structure, adhesively bonded and supplemented with me- chanical fastening. The alloy selected was the same 5251-O used for the Land Rover. Without access to any coil pretreat- ment facilities, the blanks underwent the surface pretreatment in a batch process in local shops. But from stamping on- ward, it featured no conceptual roadblock to mass production. The body structure weighed only 80 kg, about half of the equi- valent steel structure (Fig 3). While ECV3 de- monstrated the po- tential of an adhe- sively bonded struc- ture, it did not an- swer the industrial- ization of the pro- posed process up- stream of stamping. Finding a partner that could provide the solution turned out to be easy. At the time, Alcan had been ex- ploring how to enter the automotive market. Based in Mon- treal, the multinational had naturally focused on the U.S. market, where RMC and Alcoawere competing in the emerg- ing closure market. As we chronicled in Part IV of this article series, Alcan’s Kingston Laboratory had registered 6111 in 1982, but the limited number of applications did not offer much hope for a quick adoption. Further, the clo- sure market was quickly demonstrating that while an aluminum hood could re- place a steel one, it could just as easi- ly be displaced at the next model year. The body structure business would pro- vide a better alternative because unlike closures, body structures have a much longer survival time, guaranteeing a steadier and potentially much larger market. The question was how to inter- est mass market carmakers. ALCAN WORKS WITH BLT The answer came unexpectedly to Alcan’s U.K. research laboratory in Banbury, located only a few miles away from Gaydon, where BL Technology had been developing ECV3. When BLT approached the sales development de- partment of Alcan U.K. in June 1982 for aluminum sheet, it found a company with a large, capable research staff that was actively looking to enter the auto- motive market. Technical exchanges followed and Alcan soon entered into a development and licensing agree- ment with BLT to develop the system envisioned by Kewley. Further facilitat- ing the project, Banbury Laboratories happened to have researchers perfectly suited to the subject of surface pretreat- ment and adhesive development. The two companies were pioneer- ing a completely new field of R&D: Re- searchers had to invent the full testing regimen to evaluate adhesive perfor- mance, including specimen design, en- vironmental and loading conditions, and the definition of pass/fail criteria. To support the project, Alcan installed a new testing facility in Banbury with cabinets for accelerated environmen- tal testing of very large numbers of test specimens. The program expand- ed quickly and Alcan entered into its own cooperative development pro- grams with two suppliers. The first one was with Ciba-Geigy to develop a suit- able structural adhesive, whose first it- eration went by the name of LMD-1142; the second was with Leek Chemicals to commercialize a lecithin-based, ad- hesive-compatible stamping lubricant code-named AL068 that had been de- veloped internally. However, British Leyland was in a tailspin, fighting for survival. Jaguar was spun off in 1984, and developing a new aluminum body technology now had limited internal support. In early 1985, the technology was transferred into a new subsidiary, Gaydon Tech- nology Ltd., allowing research and de- velopment with Alcan to continue with outside manufacturers. There was one last collaboration with British Leyland in the summer of 1985, when it workedwith Alcan to build a demonstration fleet of six aluminum replicas of the Austin Metro. The goal was to conduct an A to B comparison Fig. 1 — David Kewley’s sketch for building a stamped aluminum auto body structure, April 1979.