On the heels of announcing an industry-first welding technology for aluminum, GM Research and Development is revealing a patented new process for adding magnesium sheet metal to vehicles. The use of magnesium, which weighs 33 percent less than aluminum, 60 percent less than titanium, and 75 percent less than steel, will help customers save money at the gas pump.
Until now, automakers have struggled to make reliably strong and non-corroding magnesium sheet metal panels using traditional panel forming methods. GM’s patented process turns up the heat on magnesium to 450 degrees Celsius (842 degrees Fahrenheit), allowing the material to be molded into precise, rigid shapes. Using this process, GM developed a production-ready magnesium rear deck lid inner panel that could remove 1 kilogram (2.2 pounds) of weight from a vehicle compared with an aluminum deck lid inner panel.
“Every gram of weight reduction matters when it comes to improving fuel economy,” said Greg Warden, GM executive director for global vehicle body engineering. “Being able to replace heavier metals with one of the lightest will help us deliver better fuel economy to customers around the world while also still providing the safety and durability they expect.”
This isn’t the first time that magnesium parts have appeared in a GM vehicle, as they are currently used for a variety of parts ranging from steering wheels to engine cradles.
“This innovative use of magnesium is just one example of how GM is leveraging breakthrough technologies that will benefit our customers around the globe,” said Jon Lauckner, GM chief technology officer and vice president of Global Research & Development. “Using high-strength lightweight materials such as magnesium and aluminum is one of the most effective ways to improve vehicle fuel economy and driving performance.”
The United States Automotive Materials Partnership estimates that by 2020, 350 pounds of magnesium will replace 500 pounds of steel and 130 pounds of aluminum per vehicle, an overall weight reduction of 15 percent. This weight savings would lead to a fuel savings of 9 percent to 12 percent.