1. Prepared by Brian Knouff Advanced Composites Engineering The All Composite One Piece Bumper by Brian Knouff 3 rd Annual SPE Automotive Composites Conference September 9 – 10, 2003 Troy, MI

2. Prepared by Brian Knouff Advanced Composites Engineering Introduction u Delphi Composites Center of Excellence set up to Affordably Integrate Composites into Transportation Industry –~ 1999 –Stemmed from columns work done in Salt Lake City u Cost penalty realized u Other benefits crucial u Class 8 truck market benefits: –Less road wear and tear –Fewer loads for those vehicles which gross out »Less traffic »Less pollution –Less maintenance for those which cube out »Better mileage

3. Prepared by Brian Knouff Advanced Composites Engineering Challenging Sacred Cows u Glass not Stiff Enough to Replace Steel u Carbon Too Expensive u Composites Can’t be Attached –adhesives work in some applications u Composites Display Poor Fatigue Properties u Process Cycle Time Too Long

4. Prepared by Brian Knouff Advanced Composites Engineering Strategy u Utilize Advanced Modeling Techniques to Optimize Composite Designs u Work with Government Labs, Universities and Commercial Partners to Investigate Alternative Precursors/Carbonization Techniques u Develop Novel Processes with Emphasis on Reduced Cycle Times u Work with Suppliers to Reduce Material Costs at High Volumes

5. Prepared by Brian Knouff Advanced Composites Engineering First Application u Aftermarket Class 8 Bumper

6. Prepared by Brian Knouff Advanced Composites Engineering Background u Metal bumpers account for about half of the market

7. Prepared by Brian Knouff Advanced Composites Engineering Background u Plastic bumpers make up the balance Thermo Plastic Polyolefin ABS Alloy FRP SMC

8. Prepared by Brian Knouff Advanced Composites Engineering Design Requirements u Natural Frequency >50 Hz u Deflect <0.5 inches with 300 lb downward load at end –represents large person stepping on bumper to clean hood, etc… u Deflect <0.5 inches with 50 lb forward load at end –represents hitting small object, windloads, etc… u Aesthetically pleasing with carbon fiber visible –Class A surface u Mass savings > 50%

9. Prepared by Brian Knouff Advanced Composites Engineering Design Topology

10. Prepared by Brian Knouff Advanced Composites Engineering Design Comparisons

11. Prepared by Brian Knouff Advanced Composites Engineering Deflections

12. Prepared by Brian Knouff Advanced Composites Engineering Weights (kg)

13. Prepared by Brian Knouff Advanced Composites Engineering All Carbon and Ni/Carbon Hybrid Bumpers

14. Prepared by Brian Knouff Advanced Composites Engineering GATS Bumper

15. Prepared by Brian Knouff Advanced Composites Engineering 2000 GATS Display

16. Prepared by Brian Knouff Advanced Composites Engineering Conclusions u Composite bumpers can be designed to replace either steel or plastic bumpers u Composite bumpers can be commercialized in today’s market at high volumes (competitive piece price) u Versus Steel –lighter –increased design flexibility –lower tooling costs u Versus Plastic –stronger –stiffer –fewer parts (1 versus 40) –lower tooling costs

17. Prepared by Brian Knouff Advanced Composites Engineering Production Launch

18. Prepared by Brian Knouff Advanced Composites Engineering Old Production u Very large volumes u Huge investments in tooling u Every part the same u Part/Plant redesign every 10 years or so

19. Prepared by Brian Knouff Advanced Composites Engineering New Production u Low to medium volumes as well as high volumes u Minimal investments in tooling u Parts constantly changing u Plants fluid (modular) and lean u Opportunity for structural polymer composites

20. Prepared by Brian Knouff Advanced Composites Engineering Production Intent u Aftermarket Class 8 Bumper u Less than 40 lbs. u Nf~20 Hz u 1 piece construction u Charcoal gray or black color u No visible fibers on front face u Textured, non-painted surface

21. Prepared by Brian Knouff Advanced Composites Engineering Part Design u Optimized for Natural Frequency u Topology dictated areas of critical mass. u Product Design –Math-based Optimization –Optimize with design responses, variables, constraints, and objectives –Grid can be made dynamic –Typical design parameters include: »thickness »fiber type »fiber orientation »fiber volume fraction »shape

22. Prepared by Brian Knouff Advanced Composites Engineering Process Development u Low-cost tooling –not steel or aluminum u Easy preform construction –no spray or robotic tooling –few piece construction –template cutting »switch to more automated process in production u Minimize equipment $ –vacuum infusion versus RTM u Experience showed that stitched fabrics too tight to vacuum infuse –needed to use rollers for GATS bumpers

23. Prepared by Brian Knouff Advanced Composites Engineering Texturing CNC Plug

24. Prepared by Brian Knouff Advanced Composites Engineering Production Process u Vacuum Infusion u Closed 2-sided mold u No injection pressure u Vacuum at exhaust pulls resin through inlet and through fabric

25. Prepared by Brian Knouff Advanced Composites Engineering Precut Preform The pattern is cut from a single sheet of 3WEAVE fabric

26. Prepared by Brian Knouff Advanced Composites Engineering Tucking Preform Single layer of 54oz is conformed into the mold

27. Prepared by Brian Knouff Advanced Composites Engineering In Service

28. Prepared by Brian Knouff Advanced Composites Engineering Micrography u Microscopic analysis displays: –Excellent wetout –Absence of voids –Good fiber distribution –Barrier coat thickness

29. Prepared by Brian Knouff Advanced Composites Engineering Make A Part u Today –Place several materials into mold –Form materials into mold –Process materials into mold –Remove part –Trim and package –Ship u Future –Place net-shape preform into mold –Process into part –Remove part –Ship