Steel News

SMDI: Lightweight Steel Twist Beam Achieves 30% Mass Reduction

12/4/2013 - Furthering its mission to help automakers meet stringent fuel economy requirements, the Steel Market Development Institute's (SMDI) Automotive Applications Council unveiled the results of its lightweight steel twist beam study today.
The project resulted in a 30% mass reduction at a significantly lower cost compared to designs using alternative materials. SMDI is a business unit of the American Iron and Steel Institute.
"With fuel economy regulations increasing rapidly, automakers are looking for every way they can to take weight out of vehicles," said Ronald Krupitzer, vice president, automotive market, SMDI. "The lightweight steel twist beam project is a great example of how currently available advanced steel technologies enable aggressive weight savings in the vehicle's suspension, thus enabling better fuel economy for the automaker and the consumer."
The results of the study indicated that the selected "U-Beam" design — based on a tubular shape using advanced steels — achieves a 30% mass reduction relative to the baseline assembly, at a modest 15% cost increase, considerably less than the cost of similar weight savings from materials like aluminum.
The original objective of the project was to develop a lightweight steel twist beam that achieved 15 to 25 percent mass reduction, with equivalent performance to the baseline design and a lower or equivalent cost to alternative materials. A twist beam assembly in commercial use today was selected for the baseline packaging, performance, mass and cost.
Funded by members of SMDI's Automotive Applications Council and members of Chrysler Group, LLC, Ford Motor Co. and General Motors Co., the lightweight twist beam project was conducted by Ontario, Canada-based Multimatic Inc. For a copy of the final report and executive summary, visit

AISI serves as the voice of the North American steel industry in the public policy arena and advances the case for steel in the marketplace as the preferred material of choice. AISI also plays a lead role in the development and application of new steels and steelmaking technology. AISI is comprised of 24 member companies, including integrated and electric furnace steelmakers, and approximately 125 associate members who are suppliers to or customers of the steel industry. AISI's member companies represent over three quarters of both U.S. and North American steel capacity.
SMDI grows and maintains the use of steel through strategies that promote cost-effective solutions in the automotive, construction and container markets, as well as for new growth opportunities in emerging steel markets.