INTERMET Introduces New Ferrous Material at 2003 SAE World Congress

Technical paper one of three presented by INTERMET at annual Congress

TROY, Mich., March 6 -- In a groundbreaking study presented at the 2003 SAE World Congress in Detroit, INTERMET Corporation unveiled a new ferrous metal that allows for the production of high-strength, safety-critical iron automotive cast components at a much lower cost than competing materials and processes.

Dr. Alan P. Druschitz, INTERMET's Director of Material Research and Development, and David C. Fitzgerald, Director of Product Engineering and Design, delivered a technical presentation introducing "MADI(TM)" (Machinable Austempered Ductile Iron) ferrous metal, which gives automotive engineers the flexibility to design suspension and powertrain components with the strength of steel forgings, but at the cost and machinability of as-cast ductile-iron castings.

According to Druschitz, the MADI material addresses one of the major stumbling blocks to the efficient casting of suspension control arms and crankshafts in austempered ductile iron: they are difficult and costly to machine. "The machining of hardened, or austempered, ductile-iron castings has been a problem in the past because of the cost of the special tools necessary to mill the material," he said. "With the MADI material, we use a special iron chemical composition and heat-treat cycles that produce a unique microstructure more favorable to normal, less costly machining methods," Druschitz said. "This is a major breakthrough, especially for high-volume automotive applications, which demand continuous improvement in performance as well as higher value."

The study, titled "MADI(TM): Introducing a New, Machinable Austempered Ductile Iron," was presented on Tuesday, March 4, 2003 at Cobo Center in Detroit. In addition to this report, INTERMET engineers presented two other technical papers at the SAE World Congress. A brief summary of each follows:

Bolt Load Compressive Stress Retention Testing of Magnesium Alloys (Paper 2003-01-0178)

Authors: Dr. Alan P. Druschitz, Eric R. Showalter, INTERMET Corp. Presented Monday, March 3, 2003

For years, the automotive industry has been using magnesium castings for structural applications, such as seat backs, seat pans, brake-pedal brackets and instrument panels. But acceptance of magnesium has been slower for more demanding powertrain applications like oil pans, transmission cases and cylinder blocks, which encounter higher temperatures. These components must retain their tensile and compressive strength through a wide range of temperatures. This paper looks at a number of new magnesium alloys that have been developed to address these issues at more competitive costs when compared with aluminum and gray iron.

New Approach in Non-destructive Evaluation Techniques for Automotive Castings (Paper 2003-01-0436)

Authors: Thomas E. Prucha, Nanda Gopal, INTERMET Corp., Robert H. Nath, Quasar International Inc. Presented Wednesday, March 5, 2003

Automotive castings increasingly are being utilized in structurally demanding and safety-critical applications. The need for reduced weight, near-net shape and more cost-effective components has resulted in a desire by automotive designers and component manufacturers to explore the reduction of conservative safety factors used for design criteria. This presentation reviews past requirements and testing approaches and sets the background for introducing an NDE (Non-Destructive Evaluation) method that evaluates parts not in terms of specific indications, but in terms of structural properties -- a much better way to determine component fitness.

With headquarters in Troy, Michigan, INTERMET Corporation is a manufacturer of powertrain, chassis/suspension and structural components for the automotive industry. INTERMET's strategy is to be the world's leading supplier of cast-metal automotive components. The company has approximately 6,000 employees at facilities located in North America and Europe. More information is available on the Internet at www.intermet.com .