MEPX
Chapter 10 of 10All chapters
  1. 1Describing a material
  2. 2Structure decides behaviour
  3. 3Metals
  4. 4Ceramics and polymers
  5. 5Composites
  6. 6How materials fail
  7. 7Processing changes properties
  8. 8Choosing a material
  9. 9Modern materials
  10. 10Materials and sustainability

Chapter 10 of 10

Materials and sustainability

Where things end up.

Energy and lifetime

Making aluminium takes enormous electricity; recycling it takes about five percent of that. Embodied energy is often larger than the energy the product uses in service.

  • Metals recycle well, mixed plastics and composites poorly.
  • Designing for disassembly decides whether recycling is possible at all.

Trade-offs

A lighter material can save more fuel than it costs to make, or not, depending on the lifetime. The honest comparison is over the whole life rather than at the factory gate.