History of Materials Chapter One

Study Notes

Origins of polymers trace back to petroleum sources.
Historically, humans utilized limited natural materials, such as stone, wood, clay, and animal skins.
Material properties can be modified through heat treatment, temperature changes, and the addition of other substances.
The automotive industry finds its foundation in the affordability of steel.
Advanced electronic devices depend on semiconducting materials for their components.

Matter can be divided into mixtures and pure substances.
Examples of mixtures include air and bronze; pure substances can be elements or compounds.
Compounds consist of combinations of elements, such as H2O (water) and CO2 (carbon dioxide).

Metals, like steel, aluminum, gold, and iron, are noted for their toughness and electrical conductivity; they can also form various oxides and nitrides.
Ceramics, such as porcelain, are strong yet brittle when crushed.
Polymers, including plastics and rubber, are derived from petroleum waste and are characterized by flexibility and stretchability.
Composites like bone, wood, and fiberglass provide a combination of rigidity and reinforcement, integrating different material properties.

Material scientists focus on the development and synthesis of new materials for various applications.
Engineering design choices consider performance, construction, and the existing materials available.
Material engineers create systems and products by evaluating material properties for optimal results.

Mechanical deformation occurs when materials experience applied loads or forces.
Key mechanical properties include elastic modulus (stiffness), strength, and resistance to fracture.

Materials are evaluated based on their ability to conduct electricity and their dielectric constants.

Thermal characterization includes heat exchange capabilities, thermal conductivity, thermal expansion, and heat capacity.

Magnetic responses are influenced by the application of magnetic fields, with common properties being magnetic susceptibility and magnetization.

Optical properties relate to light interaction, including transparency, index of refraction, and reflectivity.
Notably, humans are typically transparent to certain types of electromagnetic radiation.

Long-term performance of materials can change due to environmental reactions, such as corrosion resistance in metals.

The structure of materials is contingent upon processing methods and is categorized based on internal composition arrangements.
Five levels of structural classification include:
- Subatomic: Focuses on electrons within atoms and their interactions.
- Atomic: Concerns the organization of atoms into molecules or crystals, with varying properties (e.g., carbon in diamond form).
- Nanostructure: Consists of aggregates and particles at the nanoscale, influencing unique material characteristics.