What are the three main categories of engineering materials?

The three main categories of engineering materials are metals, polymers, and ceramics. This classification is crucial for understanding material properties and their applications in engineering.

Metals are known for their strength, ductility, conductivity, and ability to undergo significant deformation without failure, making them suitable for many structural applications. Common examples include steel and aluminum, which are utilized in construction, automotive, and aerospace industries.

Polymers, which include plastics and rubbers, are characterized by their lightweight, resistance to corrosion, and versatility in processing. Their properties can be altered significantly through various techniques, allowing them to serve in diverse applications from packaging to medical devices.

Ceramics are valued for their hardness, high thermal resistance, and electrical insulation properties. They are commonly used in applications that require durability, such as in pottery, tiles, and electronics.

The other options listed include some valid materials but do not encompass the three broad and fundamental categories recognized in the study of materials science.