AQA GCSE 2 Improving functionality Design and Technology 8552 Unit 4 Common specialist technical principles 2

Objectives Understand how materials may be enhanced to resist and work with forces and stresses to improve functionality

Starter How much weight would you expect to hold with a single A4 piece of thin card? The weight of a hamster? A laptop? A watermelon? Or the average adult?

Case study: Refold A New Zealand based design company, Refold, has created a cardboard desk that weighs only 6.5kg but can hold the weight of the average adult What advantages might a cardboard desk have over a wooden one?

From bike helmets to buildings Cardboard isn’t just being used in furniture Bike helmets, surfboards and even some buildings can be made out of cardboard How have designers manipulated a traditionally ‘weak’ material to make paper effective for use as a disposable safety helmet?

Post-it® note challenge Take a few Post-It® notes… How can they be manipulated to withstand larger forces? How can they be folded, rolled, bent or interlocked to improve resistance to forces? Can they be made weaker? How do they fare under static loads compared to dynamic loads?

Worksheet 2 There are many ways a material can be enhanced to improve its working properties and functionality Complete Task 1

Improving functionality Materials can be reinforced, stiffened or made more flexible Techniques include: Folding Bending Webbing Lamination Fabric interfacing

Folding and bending Reshaping or changing the structure of a material can reinforce it Corrugated cardboard gets its rigidity from a central layer of paper with concertina folds The curved structure of pipes and tubes dramatically increases the strength of a material while keeping it lightweight

Strengthening and enhancing Parts of a product or form might be made thicker, or have ribs, gussets or fillets added Materials can be combined to reinforce each other, increase toughness and durability, as well as safety How does this link to composite materials and alloys?

Reinforcing Reinforcing is a way of strengthening materials Metal frameworks are used in the construction of concrete housing to make reinforced concrete and increase its tensile strength How is this type of reinforcement used with other products such as glass and tape?

Webbing Webbing fabric is used to reinforce various products Its tightly woven strips are usually made from high-strength synthetic fibres such as nylon, polyester and Kevlar Suggest two products that make use of webbing? What are the advantages of using webbing in a product?

Controlling strength It’s not always about reinforcing… a product or material could be modified to make it weaker and more receptive to forces How has this plastic model kit been designed to be weaker in certain areas? Why?

Stiffening materials Lamination involves bonding two or more layers of materials together to improve working properties such as: Strength Rigidity Flexibility How is lamination used in the production of manufactured boards?

Fabric interfacing Fabric interfacing is added to textile products to make them more rigid Which parts of the product below have been reinforced in this way?

Worksheet Task 2 How have the materials on the worksheet been reinforced or enhanced to respond differently to forces?

Plenary Complete Task 3 of the worksheet Explain how each material in a single product have been enhanced to work with forces and stresses Which parts of the product have been reinforced? Have the materials been reinforced? Refer to the strategies we have covered: Folding and bending Strengthening and enhancing Stiffening