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1 Great Designs in Steel is Sponsored by: ArcelorMittal Dofasco, ArcelorMittal USA, Nucor Corporation, Severstal North America, Inc. and United States Steel Corporation

2 Future of Steel in the Automobiles of 21st Century Presenter Raj Sohmshetty, Ford Motor Company

3 Steel has been a leader in automobile applications since 1920s Background Will steel continue to be a leading material in automotive structures in the coming decades? Drivers for change Technical and economic aspects Possible future scenarios

4 Cosmological models predict that Iron Atoms The nucleus of iron has the highest binding energy per nucleon.... all the matter will become Iron! given enough time!!

5 Future of Steel in Autos - Outline Introduction & History Design Considerations Manufacturing Considerations Business Considerations Conclusion/Survey

6 Acknowledgements The following individuals helped with the preparation/review of this presentation: ArcelorMittal: Ravir Bhatnagar, USS: Guofei Chen, Bart De Pompolo, Ford: Rakshit Ramachandra, Cedric Xia, Joe Weishar, Carl Johnson, Shawn Morgans, Toyota: Umesh Gandhi References used in this presentation are mentioned on the slides.

7 Vehicle Weight Composition Vehicle Weight 1/3 1/3 1/3 Body Weight Cold Rolled Sheet Steels Chassis Weight Hot Rolled Sheet Steels P/T Weight Castings & Forgings Hydroform rear axle tube Optimize Shock/Axle Bracket Shock Tower -Eliminate powder coat Optimize design and Strengthen material and add patchwork blank if stiffness is required Radius Armdeeper draw and change material to SF590 Make integrated rear bumper / trailer hitch as on P415 DP600 Wheel Disks Common Radius arm between F250 and F450 CAE Optimize leaf springs Reduce tow hook dia by 1.0mm Micro Alloy Steel Front Springs Currently, steel is the primary material in body and chassis structures. Aluminum is a distant second primarily used engine blocks, wheels, and some closures; and in premium/niche vehicles.

8 Vehicle Material Composition 2009 Worldwide Light Vehicle Material Content All Segments - Segmented by Type of Material* - Billions of Pounds percent of the material content is ferrous based. aluminum is 7.8 percent of the total content. This equates to nearly ten million metric tons of aluminum shipments including customer offal, other scrap and spare parts Based on Forecast of 72.3 Million Vehicles actual 2009 results could be 20% lower % Castings 81% Castings Copper, Lead, Zinc, Mg, Platinum and Titanium Polymers, Glass, Wood, Rubber, Coatings, Textiles and Fluids Flat Steel Other Steel Iron Aluminum Other Metals Non Metallic's *Excludes Scrap & Includes only original Equipment Material Type Source: Ducker Worldwide

9 Vehicle Aluminum Content Trends North American Light Vehicle Aluminum Content 2009 Compared to 2006 Net Change Engines Lbs. Transmissions Lbs. losses due to smaller parts Wheels Lbs. Heat Exchangers Driveline Steering Brakes Closures Crossmembers & Cradles Suspensions Heat Shields Bumpers Body & IP Supports All Other Pounds per Vehicle Lbs Lbs Lbs. losses due to mix shift Lbs Lbs Lbs Lbs Lbs Lbs Lbs. change due to smaller parts Lbs. losses due to steel s gains Net increase of 8.24 pounds in 2009 over 2006 (primarily from Engine Blocks) Source: Ducker Worldwide

10 Drivers for Weight Reduction Fuel Economy & Emissions Safety Enhancements Performance & Features Vehicle programs are facing aggressive weight targets. Common assumptions: Incremental weight savings can be achieved by new steel technologies Substantial weight savings possible only through extensive aluminum applications

11 Vehicle Average Weight Trend 4,500 North American Light Vehicle Curb Weight - History and Forecast - The decline in curb weight from 2004 to 2009 will be the largest decline in nearly 30 years and contribute at least one MPG to fuel economy improvement Unibody vehicles are expected to average 3,471 pounds and full frame vehicles will average 4,584 pounds in 2009 Curb Weight Pound ds 4,000 3,500 3,000 4,059 3,054 3,057 3,532 3,716 3,846 4,018 3,920 3,755 2,500 2,000 '76 '82 '86 '96 '99 '02 '04 '06 '09 Select Calendar Years Source: Ducker Worldwide

12 Aluminum Vehicles vs. Comparable Steel Vehicles Data Source: Car and Driver Magazine

13 Aluminum Vehicles vs. Comparable Steel Vehicles Data Source: MSN Autos

14 Comparison of Materials Cost numbers are estimates only!

15 Comparison of Materials Source: Prof.. Mike Asbhy, Cambridge University There is no intrinsic stiffness advantage for Magnesium, Aluminum, or Titanium over Steel because they all lie on a constant Young s Modulus to Density line. Any advantage with these alternate materials in stiffness critical applications must come from geometric effects.

16 Comparison of Materials Source: Prof. Mi ike Asbhy, Cambridge University Aluminum and Magnesium have an intrinsic strength disadvantage compared to High Strength Steels because they have lower Strength to Density values. Any advantage with these alternate materials in strength critical applications must come from geometric effects.

17 Tensile Strength Load Case No Package Freedom Aluminum solution is heavier and more expensive than steel solution.

18 Tensile Strength Load Case 400% More Package Space Aluminum solution is heavier and more expensive than steel solution.

19 Bending Strength Load Case No Package Freedom Aluminum solution is heavier and more expensive than steel solution.

20 Bending Strength Load Case 25% More Package Space Aluminum solution is more expensive and requires more package space.

21 Bending Stiffness Load Case No Package Freedom Aluminum solution is heavier and more expensive than steel solution.

22 Bending Stiffness Load Case 30% More Package Space Aluminum solution is lighter, but is more expensive and requires more package space.

23 Bending Stiffness of Flat Sheet Aluminum solution is lighter, but is more expensive.

24 Torsional Stiffness of an Open Tube Aluminum solution is lighter, but is more expensive.

25 Torsional Stiffness of a Closed Tube Aluminum solution is heavier and is more expensive!

26 Durability/Fatigue Source: US Steel Website Since aluminum does not have an endurance limit, they can only be designed for a specified number of cycles. On the other hand, steel solutions can be theoretically designed for infinite cycles.

27 Structural Considerations - Summary In general, Aluminum requires more package space If package is space available, steel solutions can be redesigned! Aluminum designs cannot be simple material substitutions of steel designs Aluminum has 50% mass reduction potential for solid beam/plate bending & open tube torsion Solid beam/plate designs are inefficient and are rarely used in auto body structures (except for outer panels that can t be reinforced) Continuous joining techniques avoid open profile torsion cases For other cases, Aluminum & steel have similar mass reduction potential Aluminum solutions cost more than comparable steel solutions BMW 5-series rear bumper in aluminum (4 kg) BMW 5-series rear bumper in steel (3.7 kg) Source: FKA Report for World Auto Steel, November 2006.

28 Scratch Resistance: Steel s hardness/in-service strength is higher than that of aluminum, thus provides better performance against stone chips; and also during handling in plants. Other Design Considerations Damping: Due to higher density, steel provides better air borne noise attenuation. Corrosion Performance: Single Metal Applications: Aluminum has better corrosion performance. Mixed Metal Applications: Steel has a lower galvanic potential than aluminum and magnesium; thus is resistant to galvanic corrosion in mixed metal applications.

29 Recyclability: Steel s magnetic property and ability to mix different grades makes it easier to recycle compared to aluminum. Styling: Higher formability of steel makes it easier to meet styling requirements Packaging: Because of lower material stiffness and strength, aluminum designs usually have larger dimensions and hence require more package space Other Design Considerations

30 For similar applications, steel solutions are considerably easier to form than aluminum solutions due to: Higher forming limits Higher elongations Higher r-values Positive strain rate hardening This has implications for manufacturing robustness, material costs, cycle times, and styling. Manufacturing - Formability Major Strain mm AA5182-O 1.2mm AA6111-T4 1.2mm CR-EDDQ 1.2mm DP Minor Strain

31 Joining: Steel is easier to join in mass production environment using well established methods such as RSW and MIG welding. Aluminum joining is more complex and often requires combination of mechanical fastening, adhesive bonding, and MIG or TIG welding. Assembly: Aluminum assembly may require costly isolation systems to prevent galvanic corrosion. If aluminum castings are used, expensive machining may be required. Other Manufacturing Considerations

32 Business Considerations - Cost Legend: Ford Contour: Steel Unibody Design (BIW: 215 kg) Ford P2000: Aluminum Unibody Design (BIW: 152 kg) Audi A8 (Size Adjusted): Aluminum space-frame (BIW: 160 kg) Reference : A. Kelkar, R. Roth, & Joel Clark, Can Aluminum Be an Economical Alternative to Steel?, JOM AUGUST 2001

33 Business Considerations Price Volatility Aluminum Price ($/lb) C Steel Price ($/lb) Correlation Coefficient Between Steel & Aluminum Prices = 0.8 Relative standard deviation of steel prices (43%) has been higher than that of aluminum (27%) during Aluminum contracts are traded on an exchange may explain lower volatility? However, there is a strong correlation between steel and aluminum prices.

34 Business Considerations - Supply Growth rate world total Growth rate western world Production world total Production western world Source: European Aluminium Association World Aluminum Supply The O Carrol Aluminum Bulletin reported higher world primary capacity numbers than European Aluminum Association: - 35 million tonnes in million tonnes in 2009 Per Ducker, secondary aluminum made from scrap amounted to 13 million tonnes in World Steel Supply Source: Arcelor Mittal

35 Business Considerations - Supply Steel Aluminum New demand volume relative to world supply is much more noticeable in the case of Aluminum.

36 Reviewed design, manufacturing, and business considerations that might explain why steel has been a primary choice in auto body structures. Any change in future applications would perhaps require new aluminum technologies in areas such: new material grades material production Conclusion forming and joining recycling On the other hand, more steel application opportunities may be realized with new steel technologies and design innovations.

37 Unscientific Survey Which is a more likely in the future (2015 or later)? Scenario A: Mass produced aluminum intensive vehicles are common place. Steel is no longer a clear leader in automotive applications. Scenario N: Current material composition of automotive structures would largely be maintained. Scenario S: Steel applications increase and alternate material applications would actually see a reduction in percentage terms.

38 Great Designs in Steel is Sponsored by: ArcelorMittal Dofasco, ArcelorMittal USA, Nucor Corporation, Severstal North America, Inc. and United States Steel Corporation