chapter 2: activity 4 movie special effects. materials in science there are 4 basic types: 1....
TRANSCRIPT
Chapter 2: Activity 4Movie Special Effects
Materials in Science
There are 4 basic types:
1. Polymers (gak & oobleck)
2. Composites (paper mache)
3. Metals (aluminum& titanium)
4. Ceramics (clay or carbides)
Lets Discuss Composites
Composite:are heterogeneous materials consisting of two or more separate materials combined in a macroscopic structural unit.
ex: papier-maché
Composite Decking:
plastic (either polyethylene which is malleable or polypropylene which is rigid) and wood fiber
Examples of Composites
Concrete Driveways/Roads: Reinforced Concrete
steel rods & concrete
Examples of Composites
Examples of Composites
Airplane Composite
Material:
Do you see the many thin fibers?
Examples of Composites
Human bones
Examples of Composites
Anatomy of a Baseball
Baseball dissection
The official National League Baseball.
Baseball Dissection
The dissection begins...
Baseball Dissection
The leather cover is peeled back to reveal a layer of twine
Baseball Dissection
This first layer of thin twine is peeled away. This thin layer creates a
smoother surface on which to place the leather cover.
Baseball Dissection
With most of the first layer of twine gone, the darker, heavier yarn underneath is revealed. Many
cheaper baseballs have only a solid mass of cork/rubber amalgam under the first layer of yarn, but with a pro ball, the yarn has only just begun!
Baseball Dissection
Unraveling the dark wool yarn begins. The bits of red thread you see are the anchor points for the
heavy red stitching used on the baseball's leather cover.
Baseball Dissection
The dark yarn gives way to a layer of white yarn. Winding these layers of yarn tighter or looser can affect the elasticity of the baseball. A tighter wrap
results in a livelier ball.
Baseball Dissection
Back to dark yarn again. A cat would love this process -- countless
yards of yarn!
Baseball Dissection
The baseball shrinks as the pile of dark yarn grows. This last layer of dark yarn makes up
most of the baseball's size and mass.
Baseball Dissection
We're down to a thin layer of red rubber, and the ball is about the size of a Superball. Drop this ball,
and you'll discover that it is quite bouncy! The outer layers of yarn clearly serve to moderate the
elasticity of the rubber ball.
Baseball Dissection
One last cut, and the tiny cork core is revealed. Notice that the red rubber layer gives way to a layer of black rubber as well. The cork core is
about the size of a small grape.
Pykrete
A composite of ordinary
saw dust and
water frozen together.
History of
Pykrete
How they are made
http://composites.poly.edu/animations/index.html
Why Use Composites
Titanium-light and strong (good) but
extremely expensive (bad)
Aluminum foil is light (good) but
extremely malleable (bad)
Put them together to make a composite
Why Use Composites
So, if we put the two metals together in the right combination, we can keep the cost down and still make a strong material.
Aluminum sheets
Titanium to reinforce
Use of Composites Today
Boats (hulls) & Cars (body) Sport equipment (rackets, skis…) Artificial limbs Aircraft &
Aerospace
structures
Advantages of Composites
Low weight High stiffness High strength Low radar signature
(stealth) Extend the life of
material Can be customized for
a specific application
Disadvantages of Composites
High initial cost of research Manufacturing time Use of special raw materials
The Future
Composite materials have great potential in the decades to come.
It is an exciting field and a great career choice!
You might be the next billionaire!