Engineering materials

Introduction to Engineering Materials

  • Engineering materials are substances used in the creation of systems or mechanisms.
  • These materials have specific properties which make them useful for particular applications in engineering.
  • Materials can be classified into main groupings: metals, polymers, ceramics, and composites.


  • Metals are often used in engineering due to their strength, durability and malleability.
  • Examples of metals used in engineering include steel, aluminium, copper, and iron.
  • Specifically, steel is often used for its high tensile strength and durability, while aluminium is preferred for its light weight.


  • Polymers are commonly used in the creation of plastics and rubbers.
  • They can be lightweight and flexible, with good insulation properties.
  • Common engineering polymers include polyethylene, polypropylene, and polyvinyl chloride (PVC).


  • Ceramics are typically hard and brittle materials, which have high heat and electrical resistance.
  • They are often used for insulating electrical devices or for their heat-resistant properties in applications such as aerospace.
  • Examples of ceramics include porcelain, brick, and glass.


  • Composites are made from two or more constituent materials with significantly different physical or chemical properties.
  • These materials work together to create a substance with characteristics different from the individual components.
  • An example is fibre-reinforced plastic (FRP), where fibres provide strength and flexibility, while the plastic binds and protects the fibres.

Importance of Properties

  • Every material has a set of properties that can include hardness, strength, elasticity, ductility, melting point, and thermal conductivity.
  • Engineers must understand these properties to make informed decisions when selecting materials for specific applications.
  • The cost-effectiveness of a material is another important factor in material selection.

Testing of Materials

  • Engineers conduct material testing to determine the suitability of a material for a specific application.
  • Testing methods can include tensile testing, compression testing, hardness testing, and impact testing.
  • The results of these tests provide engineers with valuable information about a material’s properties and potential performance.

Sustainability and Engineering Materials

  • There is a growing emphasis on sustainability in engineering.
  • Engineers are expected to make choices that minimize environmental harm, which can include choosing recyclable materials or materials with a lower carbon footprint.
  • Recycled materials, such as scrap steel or aluminium, can be just as effective as new materials, but with a much smaller environmental impact.