No Light-Weight

Using lighter materials in vehicles and airplanes is nothing particularly new. For years, lighter metal alloys and composites of various kinds have been finding their way into many car parts – helping to whittle away at cost while boosting fuel efficiency. Lower mass also means lower greenhouse gas emissions – something everyone in both automotive industrial and consumer spheres can get behind.

U of Windsor professor Ahmet Alpas and his team are searching for ways to use light metal alloys in high-wear auto part applications.

“Many aluminum and magnesium alloys offer the same strength-to-weight ratio as steel and are being widely used to manufacture structural components,” says Professor Ahmet Alpas, the NSERC University of Windsor Industrial Research Chair in Tribology of Lightweight Materials. “These materials offer improved fuel economy at almost to 1:1 ratio. That means, if you could reduce the weight of a vehicle by 10 per cent, 8 per cent less fuel will be needed to run it.”

Employing alloys of aluminum and magnesium in moving engine parts, however, is a whole other ballgame, he says. For example, engine parts are mostly still constructed of cast iron, which is obviously heavy but provides excellent wear resistance and durability. Aluminum is the current alternative material of choice. “Aluminum engine blocks weigh about 40 per cent less,” Alpas notes. “Some higher-end European cars already have engines that feature all-aluminum engine blocks.”

However, the aluminum cylinders in North-American vehicles are almost all currently lined with cast iron.

“Aluminum alloys just don’t yet deliver the durability required,” Alpas observes, “and you still have the weight issue with these sleeves.”

“It’s crucial to make steady advances in these areas,” he adds. “More often than not, it’s surface tribology that limits performance of materials in automotive applications.”

In the quest to expand the range of physical and mechanical properties of commercially-available materials used in auto manufacture, there are many solutions to be explored. Alpas’ research is part of the AUTO21 Network of Centres of Excellence, a partnership between public and private sectors that currently supports more than 54 projects and 300 researchers across Canada. He and his colleagues, which include nine other PhD’s and nine graduate students, are investigating surface tribology research issues relating to manufacturing processes as well as final vehicle performance.