New lightweight magnesium car parts are helping to cut down emissions
Three toy cars sit on UBC professor Warren Poole’s desk. It’s when you pick them up that you notice the difference. The steel one is as heavy as a brick, the aluminum one feels like a litre of milk, and the lightest one, no heavier than a stick of butter, is made of magnesium.
When you scale up to real vehicles, the difference in fuel economy between the steel and the magnesium car components is 30 miles per gallon (7.8 litres/100 kilometres) compared to 40 miles per gallon (5.9 litres/100 kilometres) – which all translates to reduced emissions, not to mention cheaper gas bills for the driver. That’s why six years ago, a group of researchers and car companies set out to replace heavy steel with lightweight magnesium.
“For the average person, the reduction in the weight of a vehicle will be something they don’t notice very much other than when they go to the gas station because their vehicle will get much better fuel economy,” says Poole, a material engineering professor and scientific director of the MagNET project, a collaboration between several Canadian universities, including UBC, and auto part companies.
What drives this research?
The fuel economy of the average North American vehicle today is about 30 miles per gallon (7.8 litres/100 kilometres). By 2025, standards set by governments in both Canada and the United States will require this to increase to about 50 miles per gallon (4.7 litres/100 kilometres).
“This is a huge challenge for the car companies but it is going to be a good thing for consumers because cars will use less gasoline,” says Poole.
Ford shook up the auto industry earlier this year when it revealed its new F-150 pickup truck made mostly of aluminum. Compared to its steel predecessor, the aluminum F-150 is 300 kilograms lighter. MagNET believes it can create even lighter car components.
“Magnesium is the lightest structural material known. It is one-third lighter than aluminum and 80 per cent lighter than steel,” says Poole.
Not alone at the wheel
MagNET focused on creating a car part called the door inner–a panel on the inside of the car that separates passengers from the inner workings of the door and the outside door panel.
Car companies experimented with manufacturing magnesium door inners but found them too costly and too time-consuming–magnesium door inners took almost five minutes to make while steel doors take less than 10 seconds.
MagNET researchers created a lightweight, strong magnesium alloy and worked with Magna International, a major car parts manufacturer, to develop a procedure for making the door inner.
Video: Magnesium cars – Lighter vehicles reduce emissions
Magna and MagNET found a way to make this in a matter of seconds using existing steel door equipment. If manufacturers want to adopt magnesium in the future, they won’t need to replace expensive machines.
“I think a lot of companies would be interested in our approach,” says Poole.
General Motors was one of the biggest supporters of MagNET. If it replaced four steel door inners with magnesium, each car would be about 18 kilograms lighter.
“Of course this is just one component,” says Poole. “We could look at changing all sorts of components like trunk lids, roofs and hoods. There are many components that are candidates for the use of magnesium.”
More work to do
Replacing components like door inners would not compromise safety, assures Poole. The car body and side impact beams that protect drivers and passengers in an accident would still be made out of the heavier and stronger steel.
However, magnesium is more expensive than steel and is prone to corrosion. Given the harsh environments we live in, researchers need to ensure that magnesium parts don’t corrode too quickly. There is also the challenge of joining magnesium to other parts of the car.
Still, Poole and his MagNET colleagues are confident that magnesium will be adopted so car companies can meet their targets to reduce emissions by 2025.
“Sixty million cars are added to the road each year,” says Poole. “If each vehicle is even just 18 kilograms lighter, there would be a substantial amount of fuel saved and reduction in greenhouse gases.”
MagNET is a collaboration between industry and Canadian universities UBC, McMaster, University of Waterloo, McGill and École Polytechnique de Montréal. Funding for the project came from a Natural Sciences and Engineering Research Council (NSERC) Strategic Network grant.