Automotive use of aluminum continues to rise as North American automakers look for proven technology to reduce curb weight.
A new study by Ducker Worldwide, commissioned by The Aluminum Association, reports the percentage of aluminum in cars averages 8.6 percent, an all-time high. That's up from just 2 percent in 1970 and 5.1 percent in 1990. The use of aluminum in cars and light trucks is projected to be nearly 11 percent of curb weight by 2020.
Globally, the amount of aluminum content for light vehicles is 7.8 percent of the average worldwide light vehicle curb weight of 3,185 lbs in 2009. According to the study, growth in aluminum content is predicted to continue at a rate of four-to-five lbs per vehicle per year and approach 300 lbs per vehicle worldwide in 2020.
"As automakers seek to innovate and differentiate themselves with more fuel-efficient cars and trucks with a reduced carbon footprint, the time to use advanced materials like aluminum is now," says Buddy Stemple, chairman of the Aluminum Association's Auto & Light Truck Group.
More than 50 vehicles produced in North America contain over 10 percent aluminum content.
Vehicles manufactured by Honda and BMW average more than 340 lbs of aluminum per vehicle. General Motors, Honda, Toyota, BMW, Hyundai and Volkswagen all increased the amount of aluminum content of their North American vehicles from 2006 to 2009.
Much of the gain is coming in engine blocks and steering knuckles with penetration of aluminum blocks reaching nearly 70 percent. More than 22 percent of vehicles currently made in the U.S. have aluminum hoods, an all-time record.
"We're seeing continued growth of automotive aluminum because of the relevant advantages it offers, such as improved fuel economy and vehicle safety," says Stemple. "In fact, hybrid and diesel vehicles when paired with aluminum can actually pay consumers back faster than if those vehicles were made of heavier steel."
Material experts and body engineers surveyed in this study expect 25 percent of fuel economy improvement to come from weight savings, while powertrain experts predict 50 percent of the improvements will be the result of weight reduction.
Other options, such as carbon fiber reinforced plastics, are still on the drawing boards for parts on expensive cars, such as certain Corvette models, but remain too pricey for most vehicles.