Midterms Coverage: Materials Science and Engineering

Materials Science: Studies the relationships between material structures and properties, and includes materials chemistry and physics.
Materials Engineering: Focuses on the processing and properties of materials to enhance performance.

Processing: Involves all methods to alter a material for utility.
- Primary Processing: Initial steps like extraction and separation of raw materials.
- Secondary Processing: Steps after obtaining final materials (e.g., forging, milling).
Structure: Refers to atomic arrangements on different scales; key example is diamond vs graphite.
Properties: Measurable aspects of materials.
- Intrinsic Properties: Fundamental to the material regardless of quantity (e.g., melting point, density).
- Extrinsic Properties: Depend on the material's quantity (e.g., volume, mass).
Performance: Effectiveness of materials in application; impacted by the structure-property relationship.

Destructive Characterization: Provides detailed material information; quick and cost-effective for inexpensive materials.
Non-Destructive Characterization: Maintains the integrity of the material while assessing properties.

Ionic Bonding: Transfer of electrons, creates hard, brittle materials (e.g., NaCl).
Covalent Bonding: Sharing of electrons results in directional bonds; leads to materials like diamond.
Metallic Bonding: Shared electrons among metal atoms create conductivity and ductile properties.

Primary Bonding Forces: Strong attractions holding atoms together (ionic, covalent, metallic).
Secondary Bonding Forces: Weaker molecular forces (e.g., van der Waals, hydrogen bonding).

Quantum Numbers:
- Principal Quantum Number (n): Indicates electron shell size and energy.
- Azimuthal Quantum Number (l): Shows subshell type (s, p, d, f).
- Magnetic Quantum Number (m): Defines spatial orientation of an orbital.
- Spin Quantum Number (s): Specifies electronic spin direction.

Crystalline Materials: Have a periodic arrangement of atoms (e.g., NaCl, diamond).
Non-Crystalline (Amorphous): Lack long-range order, typically opaque.

Typical Properties: High strength-to-weight ratio, ductility, high conductivity.
Failures often occur in a ductile manner after deformation.

Metals: Good conductors, variable hardness and melting points.
Ceramics: High hardness and compressive strength, low fracture toughness; excellent thermal performance.
Polymers: Light, flexible, varying chemical resistance, often used in insulation and structural applications.
Composites: Combines materials to improve performance; used in aerospace applications.

Stainless Steel: High strength and corrosion resistance in components like turbine blades, landing gear.
Aluminum Alloys: Common in aircraft frameworks due to lightweight and high strength.
Titanium Alloys (Ti-6Al-4V): Low density and high strength for components like compressor disks.
Fiber Reinforced Polymers (FRP): Employed in structural components and protective systems, known for low weight and high strength.

Thermal Conductivity: Rate at which a material conducts heat; high in metals.
Corrosion Resistance: Ability to withstand degradation from environmental factors.
Ductility and Toughness: Ductility allows temporary deformation; toughness measures energy absorption before failure.

Aluminum: Low density and excellent corrosion resistance.
Steel: High strength and fatigue resistance.
Carbon Fiber: Lightweight with high strength and stiffness, often used in modern aerospace applications.