Teaching Modern & Smart Materials in Design & Technology A practical look at materials presented by TEP at the DATA Millennium conference Chris Rice Director of Education

The National Curriculum states … 2e: Pupils should be taught about the working characteristics and applications of a range of modern materials, including ‘smart’ materials.

Modern materials are those that are continually being developed through the invention of new or improved processes b Teflon b Optical fibres b Neoprene b Modified enzymes b Antioxidants b Genetically modified foods b Synthetic flavours b Synthetic micro fibres b Lycra blends b Polartec b Composite materials b cellular materials b Carbon or Kevlar fibre

Smart materials respond to differences in light or temperature. They sense conditions in their environment and respond to them. b Shape memory alloys b Liquid crystals in coated fabrics b Thermochromic dyes, (used to produce clothing that changes colour with light or temperature) b Modified starches

Modern Materials POLYMORPH b b (Polycapralactone) – This new polymer has a very low melting point of 62`C. It can therefore be melted underwater. As a solid it has similar properties to an engineering nylon and can be used for a wide range of prototype work. It is an ideal vacuum mould material because of its ease of moulding and its ultimate mechanical strength. To reduce its mass you can build it up around other materials such as MDF, but it can be re-formed, making it cheaper in the long term than wasting large amounts of traditional materials

Modern Materials LENTICULAR SHEET b b Improvements in production Technology have made it possible to produce sophisticated optical effects in a wide range of plastic films and sheets. Plastic fresnel lenses, for example, are now common and inexpensive. Lenticular embossing has made it possible to print and animate many images on a single substrate.

Smart materials SHAPE MEMORY ALLOY (SMA) b b A number of alloys exhibit useful memory characteristics. A combination of Nickel and Titanium (NITAL) is one of the most common. It can be heat treated to remember that when its temperature is raised to 70`C it should contract by 5%. Cooling to room temperature it then relaxes to the original length. Applications range from coffee makers (replacing bi-metallic strip) to use in garments where body heat changes the characteristics of the fabric.

Smart Product IQ CONTROLLER b b A self-contained unit capable of switching up to three outputs on and off in a controlled sequence. The programmable chip is capable of both storing information and responding to environmental changes. IQ can be built into pupils projects to give ‘in-built’ intelligence or to simulate ‘smart’ performance in sophisticated prototypes

Smart materials THERMOCHROMIC FILM b b This material has a self-adhesive plastic film, which is then over printed with a thermochromic liquid crystal ink. As the temperature changes the crystals re-orientate and produce an overall colour change. This material is used to give temperature indications – e.g. baby thermometer patches or battery condition testers.

Applications of Modern & Smart Materials in the Design & Technology scheme of work at key stage 3 Units 9A (i) (ii) and (iii) Selecting materials Main aim is for pupils to apply their understanding of properties of materials. Food, Textiles and RM bias, with similar outcomes. Pupils have opportunity to learn about modern materials/ingredients, modified starches. Raise concerns re: biodiversity, GM crops, growth hormones and antibiotics. Blending polyester with cotton to reduce creasing (Marks & Spencer non-iron shirts). Micro fibres, thermochromic dyes, composites. Fabrics that change colour when exposed to extremes of heat or cold.

This unit of work is intended to supplement or replace the Design & Make assignment contained within unit 9A(ii) (Selecting Material, Focus:Resistant Materials) of the National Scheme of Work at Key Stage 3 for Design & Technology AIM The main aim of this unit is for pupils to apply their understanding of a ‘Smart’ material (in this case, Thermochromicfilm) when designing. They should be able to identify a need for a product that could utilise this technology and go on to make their design.

“Organise a range of activities that give pupils the opportunity to learn about the diversity of a product.” Explore the use of modern materials. Carry out a Product Analysis. PRODUCT EVALUATION

Focussing on the knowledge, skills and understanding they will need during the DMA. Carry out test procedures on samples of materials Using the working characteristics of different materials Use their knowledge of the properties of materials Focussed Practical Tasks

Set the pupils a DMA in which they: Select materials according to their characteristics. Evaluate the materials chosen. Explore the uses of modern materials and use them sympathetically Design and Make Assignment