Informative Speech - Metals
Purpose: My purpose is to inform the audience of how different types of steel are formed by
explaining the different mechanical properties of Iron and Carbon compositions.
A. Have you ever noticed that some steel, such as a long bridge is able to bend and have slack, whereas other types of steel are more brittle yet much harder, such as a propeller. If a bridge were more brittle, a strong perpendicular wind could easily break it in half, and a soft propeller would not give you the torque to accelerate to high velocities because the water would have more effect on it's definition.
B. These properties have real life relevance, when steel was discovered in the middle ages it quickly became much more popular than bronze, because of its strength. (Kramer, E. 1992) Steel was a revolution that would affect the world from then on.
II. Statement of Central Idea
A. The change of iron and carbon to steel has had a profound affect on the world, it has revolutionized science and technology that we understand in the 20th century.
B. Different ratios of carbon to iron and different hardening and cooling techniques have furthered our advancements in reaching a utopian compound that has equally elastic and plastic deformation properties.
C. Separate processes have been distinguished between the carbon-iron ratio, which allow us to make steel either brittle or elastic.
A. First issue- Dislocations are the strength of all forms of steel. Each individual dislocation forms with another to create a "knot" that holds the matrices of atoms together. The...