CCEA A-Level Life and Health Sciences 0008
Experimental Techniques
Human Body Systems
Physical Chemistry in Industrial Processes
Brain ScienceDouble Award
Material ScienceDouble Award
Medicine, Drugs and Clinical TrialsDouble Award
Scientific Method, Investigation, Analysis and Evaluation
Organic Chemistry
Medical PhysicsA2 option
Sound and LightA2 option
Genetics, Stem Cell Research and CloningA2 option
MicrobiologyDouble Award
Oral Health and DentistryDouble Award
Histology and PathologyDouble Award
Analytical Chemistry TechniquesDouble Award
Enabling TechnologyDouble Award
Material Science
Smart materials
- 3 things to know
- AS 5
Overview
Shape-memory alloys in stents and staples, piezoelectric materials, quantum tunnelling composites, thermochromic, photochromic and electroluminescent materials, and choosing a smart material.
What you need to know
Answer each one before you reveal it.
What are the defining features of a shape-memory alloy?
How is a shape-memory alloy used in a self-expanding stent?
Questions from this subtopic
Each one with the model answer underneath.
- 1
What is a smart material?
Model answer
A smart material has one or more properties that change significantly in response to an external stimulus. The change is reversible and can be triggered by temperature, light, stress or voltage.
- 2
What are the defining features of a shape-memory alloy?
Model answer
A shape-memory alloy can be deformed when cool and returns to its original shape when heated above a transition temperature. Nitinol, an alloy of nickel and titanium, is the commonest example.
- 3
How is a shape-memory alloy used in a self-expanding stent?
Model answer
The nitinol stent is compressed and delivered through a narrow catheter into a blocked artery. Body warmth makes the stent expand to its remembered shape, holding the artery open.
- 4
What are the defining features of a piezoelectric material?
Model answer
A piezoelectric material produces a potential difference when it is squeezed or bent. The material also changes shape slightly when a potential difference is applied.
- 5
Give three uses of piezoelectric materials.
Model answer
Piezoelectric crystals produce the spark in gas lighters and detect pressure in sensors. Piezoelectric materials also generate and receive ultrasound in medical scanners.
- 6
What are the defining features of a quantum tunnelling composite?
Model answer
A quantum tunnelling composite contains metal particles dispersed in an insulating polymer. The composite insulates when relaxed but conducts when compressed.
Other ways to work this
The same content, four other ways.
What is inside Levo
Six ways to work the same material.
Every question in Material Science, on a schedule.
Attempt a question from memory, write the correct version, then attempt it again. Levo records the jump between your first attempt and your last, and brings each question back on the day you are due to forget it.
Or £46 a year, about £3.83 a month. Cancel anytime.