Metals Overview

Select the Ferrous Alloys

• Steel

• (Cast) iron

• light alloys

• copper

• nickel

Light Alloys​ ​ ​ ​

• Lithium
• Nickel

• Magnesium
• Titanium
• Steel

Why are alloying elements added​ ​ ​

• to improve processing
• to alter the structure
• to improve the properties
• to make it worse
• to cause defects

Most metal alloys are...

• Polycrystalline

• Monocrystalline

• processed from a melt

• processed from a powder

• dominated by a single element

Densities of Metals

• metals have close-packing (metallic bonding)

• metals have distant packing (metallic bonding)

• metals often have large atomic masses

• metals often have small atomic masses

Densities of Ceramics

• ceramics have less dense packing than metals

• ceramics have more dense packing them metals

• ceramics often have lighter atomic masses

• ceramics often have heavier atomic masses

densities of polymers

• polymers have low packing densities

• polymers have high packing density

• polymers are often amorphous

• polymers often have heavier elements

Metals are often used when these properties are critical:​ ​ ​

• stiffness
• strength
• fracture toughness
• wear resistance
• flexibility