Which key will withstand more stress, the newer composites fiberglass or the older plastic?

We used four tests to determine this:› Laundry Test› Three-Point Bending Test› Hot/Cold Test› Torsion Test

If we make the keys out of a stiffer, or more flexible, material such as fiberglass or different plastics, then the keys will be less likely to break.

Hypothesis

We predict that the fiberglass key will withstand the most stress and outlast any of the other types of keys.

Keys were developed over 3500 years ago Keys are tools used for opening locks The oldest known lock is estimated to be 4000

years old People first started trying to improve keys in

1778

Fiberglass Composite Hot Water Plastic Resin Hardening agent Sand paper Freezer Tape Breather Wrapping

Materials List

Materials List Cont.

Ban saw Release Film Scissors Marker Tongue depressors Paper Cup Scale

Procedure

1. Select composite materials and prep tool2. Calculate and mix resin and hardening agent3. Mix resin mixture with fiberglass 4. Make bag for composites5. Leave out to cure for at least 24 hours6. Cut out and sand keys7. Test new composite keys

Procedure

Laundry Test

• We sent a key through the laundry to find out how it would hold up, and if it would still be in usable condition.

Hot & Cold Test

To simulate weather conditions in either Winter or Summer, we are going to freeze the cards and bend them. As well as heating them up in hot water and bending them.

Three Point Bending Test

A test in which the edges of the card are held and pressure is added to the center to see how much the key can bend before it breaks.

Torsion Test

The torsion test will show how durable the side strengths are and to simulate your card being put in your pocket long ways to bend it around your hip. The torsion test is just another test used to identify the flexibility and durability of a key in a different manner.

Data/Results

Our key cards have some of the same properties of the plastic cards.

The fiberglass keys and the plastic keys seemed to be equal in all the tests.

The only real difference found is in the way the key looks.

Conclusion

Our keys work as actual keys, but they aren’t any better than the keys already in use.

This project helped us to learn about new and different possibilities that could be used in future testing.

Future Study

Other things we would like to test are: Different materials for the keys such as:

-Kevlar (Impact Resistance)-Graphite-Metal

Acknowledgements

Thanks To› Mrs. Morgan› Mrs. Scott› Ms. Miller› Mr. Eddy› Mrs. Gallegos› Mr. Smith

Sources

http://www.tillwite.com/about_keys_locks.asp http://inventors.about.com/library/inventors/

bllock.htm http://science.jrank.org/pages/3989/Lock-Key-

History.html http://www.plasticsmag.com/article_images/

Technological%20Bend%20Test.JPG

Questions