Steel beats aluminum
The Bloomberg News story " Rules for more efficient cars could make aluminum golden " (Jan. 1 and TribLIVE.com) contains inaccuracies. In the mid-'90s, the government's Partnership for a New Generation of Vehicles project ignited discussions of steel being replaced by aluminum. Meanwhile, the first generation of advanced high-strength steels was introduced. Stronger and more formable, they replaced traditional steel, rendering aluminum's desire to dominate vehicle bodies wishful thinking.
Experts confirm today's third generation of advanced high-strength steels puts steel and aluminum structures on par concerning weight. Analyst Lloyd O'Carroll's suggestion that "a pound of aluminum can replace 2.5 to 3 pounds of steel" in 2012 is just plain wrong.
The story correctly notes that aluminum is three times as expensive as steel and that for aluminum to reach 20 percent in the average car, sales of an additional 5.3 million tons of it would be required. According to the Aluminum Association, producing 5.3 million tons would result in approximately 58 million tons of CO2-equivalent emissions. By comparison, producing 5.3 million tons of steel would result in about 11 million tons of CO2-equivalent emissions.
Aluminum's higher cost, much higher emissions and comparable weight explain why, in future vehicles, steel will be replaced by steel, as it was in 1996 -- applying the latest advanced technologies that make it the most lightweight, green and cost-effective material.
Lawrence W. Kavanagh
The writer is president of the Steel Market Development Institute (autosteel.org).