1. Investigation of a bullet impact December 1 st 2010 Engineering 45 Fall 2010 Kevin Chee Shauna Fong Max Heald

2. The Purpose The Setup The Results

3. Purpose In this experiment our goal was to investigate the effects of a bullet impacting different materials. We accomplished this by cross sectioning the material at the bullet impact site then looking at the microstructure.

4. Setup Material Preparation: – Steel: (2 thin, 2 thick) 1 of each thickness, heated to 900⁰C then furnace cooled 1 of each thickness, heated to 900⁰C then quenched to room temp

5. – Brass: 1 sample 25% CW 1 sample 0% CW

6. Gun used: 22 caliber rifle

7. Range: ~10 ft

8. Mount: materials were mounted on single wooden board via zip-ties.

9. Thin steel furnace cooled impact

10. Thin steel quenched impact

11. Brass 25% CW

12. Brass w/o CW

15. Impact (head on)

16. Impact (side view) Thick steel Thin Steel (quenched) Thin Steel (furnace cooled) Brass no CW Brass 25% CW

17. Furnace cooled steel Microstructure: using Nital etching solution Impact direction

18. Furnace cooled steel Microstructure #2

19. Furnace cooled steel Microstructure #3

20. Furnace cooled steel Microstructure: using FeCl 3 etching solution

21. Furnace cooled steel Microstructure: using FeCl 3 etching solution #2

22. Quenched steel

24. Quenched Steel

25. Brass no CW microstructure

26. Brass 25% CW

27. Shotgun slug vs Bulletproof vest

28. Aknowledgements Thanks to Johnson’s winery in Alexander Valley for letting us use their location.