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Daimler-Benz has developed a new method of casting aluminium engine blocks
that cuts carbon dioxide emissions by 36 per cent. In the traditional process
the engine block is cast in a sand mould, cooled so that the sand can be removed
from the cylinders, and reheated to 530 掳C to harden the metal. In the new
process, a mixture of sand and resin forms the mould. The resin burns off and
the sand can be blown away while the metal is being hardened, so the engine does
not need to be reheated.