Current Advances in Low Density SMC for Automotive Class A Applications AOC

Transcription

1 Current Advances in Low Density SMC for Automotive Class A Applications AOC

2 Outline Class A 1.2 SPG Low Density Development of Current Low Density Class A SMC Accomplishments of Current Low Density Class A SMC Properties of Low Density Class A SMC Current Usage Next Steps High Strength Structural and Class A 1.2 SPG LD Future Developmental Work Summary

3 Development of Current Low Density Class A SMC Low Density SMC mostly used in non-appearance applications Heat shields Body panel supports; etc. New Low Density Class A Body Panels Requirement is for a 1.2 specific gravity or lower Surface aesthetics comparable to standard density (1.9 SPG) Class A SMC Physical Properties Must meet current low density SMC specifications Better if they could meet the standard density SMC specifications Achieving both required mechanical properties and Class A surface aesthetics has been a challenge. Now low density systems of 1.2 specific gravity offer comparable performance in both respects to standard density (1.9) Class A systems at up to a 46% weight savings vs steel.

4 Development of Current Low Density Class A SMC Demand for Better Fuel Efficiency Improvement of mileage Lower carbon emissions Competitive Materials High Strength Steel At the point of diminishing returns in terms of weight reduction Aluminum Requires major re-tooling of the forming & assembly processes Carbon Fiber High raw material cost and limited carbon fiber availability

5 Accomplishments of Current Class A 1.2 Low Density

6 Surface Properties: Low Density Class A Description Loria Index O P DOI Typical Structural LD Standard Density Class A 1.9 SPG Current Class A Low Density 1.2 SPG

7 Mechanical Properties Ford LD Specification WSS-M3D188-A: Tensile Strength (MPa) Minimum Specification Typical Structural LD Current LD

8 Mechanical Properties Ford LD Specification WSS-M3D188-A: Tensile Modulus (GPa) Minimum Specification Typical Structural LD Current LD

9 Mechanical Properties Ford LD Specification WSS-M3D188-A: Tensile Elongation (%) Minimum Specification Typical Structural LD Current LD

10 Mechanical Properties Ford LD Specification WSS-M3D188-A: Flexural Strength (MPa) Minimum Specification Typical Structural LD Current LD

11 Mechanical Properties Ford LD Specification WSS-M3D188-A: Flexural Modulus (MPa) Minimum Specification Typical Structural LD Current LD

12 Other Properties Ford Structural Low Density Typical Structural Current 1.2 Class A Specific Gravity ( ) WSS-M3D188-A LD LD (ISO 1183, Method A) Water Absorption (max 1.3%) no blisters Glass Fiber Content (33 45%) by weight 38 38

13 Current Usage of Class A Low Density SMC The material containing the AOC Class A, Low Density resin system is currently in production on the GM C7 Corvette and has been so for over a year. It has now been approved at two other OEMS. This Low Density Class A SMC is targeted for a new production application with a major OEM next year.

14 Next Steps Explore the boundaries of the current 1.2 SPG system. Lower specific gravity versions Higher Strength versions. Progress on lower density class A and higher strength Class A and structural versions has shown promise.

15 High Strength Structural and Class A 1.2 Low Density A series of modifications to the 1.2 specific gravity materials has yielded: Higher strength structural SMC Higher Strength Class A materials targeted for 1.25 specific gravity. A key point to keep in mind is the concern for the loss of tensile modulus during high temperature painting. Even though tensile modulus is important at room temperature, it is more important through high temperature painting cycles.

16 MPa Higher Strength Structural Low Density Tensile Strength Current LD Std. Structural Structural LD Temperature ºC

17 GPa Higher Strength Structural Low Density 12.0 Tensile Modulus Current LD Std. Structural Structural LD Temperature ºC

18 MPa Higher Strength Structural Low Density Flex Strength Current LD Std. Structural Structural LD Temperature ºC

19 GPa Higher Strength Structural Low Density 14.0 Flex Modulus Current LD Std. Structural Structural LD Temperature C

20 Surface Properties: Higher Strength LD Class A Description Loria Index O P DOI Typical Structural LD Standard Density Class A Higher Strength Class A Low Density

21 Mechanical Properties Higher Strength LD Class A Ford Low Density WSS-M3D188-A High Strength Class A LD Tensile Strength at Break, min 42 MPa 92.2 Tensile Modulus at Break, min 6.8 GPa 9.4 Tensile Elongation, min 0.8% 1.3 Flexural Modulus, min 5.2 GPa 9.9 Flexural Strength, min 115 MPa Specific Gravity ( ) 1.28 Water Absorption, max 1.3% no blisters 0.6 Glass Fiber Content (33 45%) by weight 47.7

22 Future Development Work Ultra Low Density Class A Lower than 1.2 Class A specific gravity specific gravity specific gravity

23 Ultra Low Density Class A: Surface Characteristics Description Loria Index O P DOI Below 1.0 SPG to 1.1 SPG Typical Standard Density

24 Mechanical Properties: Ultra Low Density Class A Ford Low Density WSS-M3D188-A Below Tensile Strength at Break, min 42 MPa Tensile Modulus at Break, min 6.8 GPa Tensile Elongation, min 0.8% Flexural Modulus, min 5.2 GPa Flexural Strength, min 115 MPa Specific Gravity ( ) Water Absorption, max 1.3% no blisters Glass Fiber Content (33 45%) by weight

25 Summary None of the sheet molding compounds discussed exhibited any issues during the manufacture and molding of the material. The new AOC Low Density resin systems exhibited results that were favorable to the Ford Low Density Structural Specification. Mechanical Properties exceed Ford s specification WSS-M3D188- A. Some aesthetic results were superior to the surface characteristics shown for a standard density Class A system. AOC now has a Class A resin system that is currently in production on the Chevrolet Corvette. The Class A system has also been qualified at Ford and Chrysler. Other OEMS are in the process of qualifying the Class A system as well.

26 Summary We believe that the work done affords automotive OEMs the opportunity to immediately reduce the mass of Class A closure panels without having to change their manufacturing and assembly processes. These materials provide a cost competitive alternative to aluminum and carbon fiber composites and are readily available. Additional benefits include: greater design freedom, parts consolidation, lower tooling cost, dent/damage & corrosion resistance and excellent surface aesthetics. We are currently focusing on improving the Ultra Low Density versions for mechanical properties

27 JEFF KLIPSTEIN AOC TECHNICAL SERVICE SPECIALIST (219) WORK (219) FAX (330) CELL