Lightweighting Iron Alloys in Thin-Wall Castings
Improved melt processing could decrease the wall thickness of certain ductile iron cast automotive parts by up to 50 percent, saving up to 50 percent in weight.
Posted: July 9, 2015
Casting parts from molten iron is a well established process that has been transformed recently by technological advances. The consortium from the lightweight metals institute LIFT (Lightweight Innovations for Tomorrow; Detriot, MI) has chosen to investigate those innovations in melt processing as its first technology acceleration project.
Grede Holdings LLC (Wauwatosa, WI) and Michigan Technological University (Houghton, MI) are the industry and research lead partners on this project, which will focus on reducing the amount of metal used in making an automotive transmission differential case, similar to core product designs provided by Grede and Eaton Corporation (Irvine, CA). Other collaborators in the group besides Grede, Michigan Tech and Eaton include the American Foundry Society, Comau, PDA and Massachusetts Institute of Technology.
“People don’t often think of iron alloys as lightweight, so this first project shows how we are really changing the thinking about manufacturing in America,” said Larry Brown, the executive director of LIFT. “We expect that by working together through us, the collaborators from industry and academia will be able to accelerate the speed of turning their R&D into a production line process.”
By integrating and implementing improved manufacturing methods with different available alloys, there is potential to decrease the wall thicknesses of ductile iron cast parts by up to 50 percent. That, in turn could save from 30 percent to 50 percent weight savings, depending on the load requirements of the part.
Jay Solomond, the vice president of engineering and technology at Grede, said, “During early product development, parts are designed to meet the limiting performance criteria. This often results in parts being globally designed with extra material to meet the minimum requirements. However, this also often results in unnecessary weight to the overall part. We want to put the right amount of material just where it needs to be, and to replicate that on a scale for automotive production lines.” Grede expects to do a significant amount of work on the project in its foundry in St. Cloud, MN.
Paul Sanders, the associate professor of materials science and engineering at Michigan Technological University, said, “Iron alloys have high stiffness and good strength. We will optimize composition and cooling rate utilizing Grede’s new high precision molding machines to create thin-wall ductile iron components while maintaining desired microstructures and performance. We look forward to integrating upfront modeling with local cast properties to design optimized component geometries. We hope to bring this lightweight design methodology into Grede’s production facility.”
James Larsen, the manager of materials and power transfer system engineering for Eaton’s Vehicle Group, said, “In our ultra-competitive product markets, timelines to achieve cost and weight reduction are critical. LIFT is providing a valuable service by facilitating collaboration that will help speed up how we are able deliver great concept ideas into our customer’s products. We are involved because we are confident this work will translate into delivering value to them.”
The American Foundry Society is involved in the project to ensure that workers in the industry have opportunities to learn how to use the new materials and techniques that will come out of the project. The Society conducts workshops, webinars, and other training sessions through its AFS Institute.
LIFT is one of six manufacturing innovation institutes announced to date and supported by the federal government. LIFT receives its funding from the U.S. Department of Defense administered by the U.S. Navy Office of Naval Research. Approximately 44 percent of the estimated $1.34 million costs for this melt processing technology acceleration project will be paid for by the federal government, the other 56 percent will be shared by industry and research partners.
Brown added, “We expect to be seeing results from this first project in about a year. And with nearly 90 industry and academic partners in our consortium, we expect to be announcing more technology projects on a regular schedule, as well as important education and workforce development initiatives to make sure we have people well trained in the innovations we are generating.”