A "game-changing" semi-solid aluminium die-casting system that moulds metal at the texture of ice cream offers major benefits for Canada's aluminium industry, the global auto industry and the environment.
The system, which took seven years and $12 million to develop, is likely to make critical brake and suspension components made of aluminium far more common in inexpensive mass-produced vehicles. In recent years, the auto industry has driven hard to reduce vehicle weights for environmental reasons. Lighter cars need less energy to move, whether they use gasoline, electricity or more exotic fuels.
Until now, most safety components such as brake and suspension parts have remained heavy iron or steel because they're easier to build at the needed strength. Only high-end cars use forged aluminium brake or suspension parts.
The automated system, called a swirled equilibrium enthalpy device (SEED), changes that. It allows semi-solid aluminium to die-cast parts with the same strength as high-quality forged aluminium at far less time and cost.
SEED combines sophisticated control systems and robotics to reliably produce an aluminium slurry the consistency of ice cream, which is die-cast at a precise temperature into complex shapes. Semi-solid aluminium makes stronger cast pieces than liquid metal because it fills moulds more consistently and cools more evenly, with less internal stressing. After helping to develop the furnace, a Chicoutimi-based company called STAS saw the potential of licensing the system to aluminium foundries worldwide.
Canada is the world's second-largest exporter of aluminium ingots, and aluminium production and manufacturing support 17,500 jobs while generating $12 billion in yearly revenue. Quebec produces more than nine-tenths of the country's aluminium, nearly half of it near Saguenay.
In 2002, STAS joined the NRC Aluminium Technology Centre (NRC-ATC) and primary producer Rio Tinto Alcan — key players in the Saguenay-Lac St. Jean aluminium transformation cluster — to help develop the SEED system. Rio Tinto Alcan researchers created the concept, but as Rio Tinto Alcan produces aluminium from bauxite ore rather than fabricating intricate aluminium components, it partnered with NRC-ATC to help develop the technology. NRC-ATC's mandate is to help diversify the local economy from its sole reliance on aluminium smelting toward small and medium-sized enterprises making value-added products.
"SEED is an automated system with a very high level of sophistication and intelligence built in," says Pascale Côté, R&D manager of STAS. "This technology is basically for automotive applications, with an orientation toward light vehicles — it could really impact on the emission of greenhouse gases."
First-generation SEED systems have already been sold to R&D centres at Yamaha as well as the European automotive suppliers Lebelier and CIE, where they're being used to evaluate new manufacturing processes and parts.
"SEED has huge potential, because it completely changes the way things are done," agrees Alain Simard, the business development officer at NRC-ATC. "It's a disruptive technology. It offers the same strength as steel or forged aluminium, but at a fraction of the cost."
The aim for SEED system developers was two-fold: to help auto parts makers build better products; and to make systems affordable and easy to retrofit in large existing foundries and small operations. The partners targeted car parts manufacturers to start because they make high-volume items and the auto industry urgently wants to lighten vehicles.
While the SEED technology may disrupt automotive markets, it can be added to existing foundries — in stages if necessary — without disrupting their internal processes.
"The customer base is already there. SEED just improves what they're doing at the moment," says Simard.
