Question

A) Explain the general responses of ceramics, metals and polymers to mechanical and electrical loads in terms of both primary and secondly chemical bonds

B) Classify the following materials as a polymer, metal, ceramic, or composite: Boron Nitride, Bricks, Plexiglas, Concrete and Manganese.

Answer 1

A). Ceramics -

Response to mechanical loads - In ceramics, due to the combined ionic and covalent bonding mechanism, the particles cannot shift easily. The ceramic breaks when too much force is applied, and the work done in breaking the bonds creates new surfaces upon cracking.

Response to Electrical loads - Ceramics are probably best known as electrical insulators. Some ceramic insulators (such as BaTiO₃) can be polarized and used as capacitors. Other ceramics conduct electrons when a threshold energy is reached, and are thus called semiconductors.

Metals -

Response to mechanical loads - Metals have high mechanical resistivity due to strong metallic bonds. They have high tensile strength. They are tough, rigid, ductile and mostly show linear plastic deformation.

response to electrical loads - Metals are good conductors of electricity due to the presence of free electrons. The conductivity of metals is high and conduct electricity.

B). Boron nitride - Ceramic

Bricks - Composite

Plexiglas - Polymer

Concrete - Composite

Manganese - Metal