Smart & Modern Materials

Watch first

GCSE DT RevisionSmart and Modern Materials

Key facts

Smart materials — respond to a stimulus

Shape Memory Alloy / Nitinol — returns to its pre-programmed shape when heated. Dental braces, medical stents, spectacle frames.
Thermochromic pigments — change colour with temperature. Baby food spoons, forehead thermometers, mood rings.
Photochromic pigments — change colour/tint with UV light. Self-tinting spectacle lenses.
Quantum Tunnelling Composite (QTC) — conducts electricity when compressed. Pressure sensors, touch controls.
Electrochromic glass — changes opacity when voltage applied. Privacy glass, smart windows.
Key definition: a smart material reacts to a stimulus (heat, light, pressure, electricity) and changes one of its properties in response.

Modern materials — developed post-WW2

Carbon Fibre Reinforced Polymer (CFRP) — extremely high strength-to-weight ratio. Aerospace, racing cars, bicycles, sporting equipment.
Kevlar — very high tensile strength, good impact resistance. Bulletproof vests, helmets, brake pads.
Graphene — single carbon atom layer, incredibly strong, excellent conductor. Currently experimental.
Gore-Tex — waterproof yet breathable membrane. Outdoor clothing.
D3O — soft and flexible but stiffens on impact. Sports protective equipment.
Titanium alloys — high strength, low density, excellent corrosion resistance. Aerospace, medical implants.

Exam questions — 3 questions · 9 marks · real AQA 8552 past papers

1 markSmart material definitionAQA 8552 Nov 2021 Q9

Which best describes a smart material?

A A material made using the latest computer-controlled manufacturing

B A material developed after WW2 with enhanced properties not found in traditional materials

C A material that reacts to a stimulus (heat, light, pressure) and changes one of its properties in response

D A material that can be recycled without losing any properties

1 markCFRP useAQA 8552 Jun 2024 Q5

Why is carbon fibre reinforced polymer (CFRP) used in aerospace rather than steel?

A CFRP is cheaper and easier to manufacture than steel

B CFRP has a much higher strength-to-weight ratio than steel, providing structural strength at a fraction of the mass

C CFRP is more ductile than steel making it easier to form complex shapes

D CFRP conducts electricity better than steel improving safety in lightning strikes

4 marksEvaluate Kevlar for a protective helmetAQA 8552 style

Evaluate Kevlar as a material for a protective sports helmet. Consider properties and limitations. (4 marks)

Hint: At least TWO genuine advantages and at least ONE limitation. Be specific — name the property and explain why it matters for a helmet specifically.

+40 XP

Smart materials — respond to a stimulus

Modern materials — developed post-WW2

Module complete!