DETROIT – General Motors is testing a new treatment for lightweight magnesium sheet metal that allows it to be used in automotive applications as an alternative to steel and aluminum. GM stated that magnesium weighs 33% less than aluminum, 60% less than titanium, and 75% less than steel.

According to GM, up until now, automakers haven’t been able to make reliably strong and non-corroding magnesium sheet metal panels using traditional panel forming processes. GM’s new process resulted in the development of a production-ready magnesium rear deck lid inner panel. The panel was able to withstand 77,000 robotic slams and 250-kilogram impact drops without issues. The automaker was able to remove 1 kg (2.2 lbs.) of weight with the magnesium panel (compared with an aluminum deck lid inner panel). The proprietary treatment also allowed the magnesium to resist 10 consecutive weeks of 24-hour environmental tests that involved salt spray, 100 percent humidity, and extreme temperatures.

Estimates of broader use of lightweight magnesium in automotive components by the United States Automotive Materials Partnership state that by 2020, each vehicle will utilize 350 lbs. of magnesium, replacing 500 lbs. of steel and 130 lbs. of aluminum, which is an overall weight reduction of 15%. According to GM, this reduced weight would improve fuel economy between 9 and 12%.

The automaker stated its goal is to expand the use of low-mass parts on its vehicles and plans to pursue licensing opportunities related to this new, proprietary treatment process.