A2 Design and Technology Resistant Materials Notes (EDEXCEL)Watch
Good luck all!
3.1 Modern technologies and materials
The creation and use by industry of modern and ‘smart’ materials
A filter to reduce unwanted wavelengths for the end result.
(Polaroid Filter used)
A variable filter to reduce unwanted wavelengths for the end result.
(E.g. Glasses that dim when in sunlight)
o Glass for welding shields:
A photocell in the helmet creates a current when the bright light hits it, causing LCD in the viewing screen to darken.
o Pollution-free energy supplies:
o Solar panels:
Expensive, initial setup cost (approx 20yrs before return is made)
Low energy produced, weather and location dependant.
1. Heating water: Copper pipe network sat on black screen (to attract heat) this is pumped into heating system, water feeding into radiators.
Benefits: Doesn’t require gas boiler to run (usual method of water heating)
2. Generation of electricity: Use Photovoltaic cells to generate energy.
Pros: Reduces the dependence to generate energy which is likely to be have generated with a co2 producing method.
Cons: Ugly, the solar panels may have been produced with a high co2 manufacture process.
For use in areas where there will be high temperatures, able to resist the high temperatures (e.g. brake discs on F1 cars or space shuttles).
o Shape memory alloys (SMA):
Generally smart materials; they have been designed to have a specific output from a defined stimulus or input.
Remembers its original shape.
Most SMA’s react to heat, and when it is given heat it uses its memory to be restored to its original shape.
For example: Stents are used in heart surgery, inserted into an artery which may be blocked and then by applying a stimulus to warm it up to the stent which then changes its shape and is allowed to push out on the artery making it wider, reducing the risk of heart attack or stroke.
o LCD displays:
Used for welding screen, and of course LCD displays.
o Piezo-electric actuators:
Used to create a current using pressure on crystal, omitting a high voltage but small current. This is reversible. By exciting the crystal, movement can be produced from the electrical signal. Can come in different forms.
For example Piezo speakers (like in phones etc)
A composite takes properties of several materials an combines them to produce a new material
o Carbon fibres:
Carbon fibre is a material consisting of extremely thin fibres about 0.005–0.010 mm in diameter and composed mostly of carbon atoms.
o Smart composites:
Same principal as smart materials – if you want a particular reaction to a stimulus, you design it to do what you want.
o New materials as used in the computer and electronics industry:
o Brake Lights
Originally used filament bulbs, but they get hot/have to heat up so there is a delay between the pedal depressed and the light coming on
Now use LED’s lights, these are much brighter for far less power (less strain on battery) and the react instantly (no delay for turning on).
The impact of modern technology and biotechnology on the development of new materials and processes.
o Genetic engineering in relation to woods
Altering genes to provide quicker growing trees, or to supply wood that resists wear, rot or infestation.
o The use of micro-organisms to aid the disposal of environmentally-friendly plastics.
Bio-degradable plastic – e.g. Co-Op carrier bags
o The recycling of materials - producing materials that are totally recyclable.
Modification of properties of materials
Enhances properties (like composites do for other materials)
E.g. Steel is stronger than its primary element iron
o Heat treatment:
Method to alter the physical (and sometimes chemical) properties of a material by heating or chilling to extreme temperatures.
E.g. Annealing: heating a metal then work hardening it.
Tempering and quenching: Heat to temp then cool to change properties (colouring to determine temp reached).
o Work hardening:
Working on a material (hitting it) to strengthen it.
Note: Bending a metal bar until it snaps is work hardening (the bend in becoming stronger but more brittle until it separates.
o Age hardening (also called precipitation hardening):
Increases yield strength of malleable materials
(How much force it needs to break it)
Powdered material heated in a furnace until particles stick together.
Method for creating man-made polymers by linking monomers together and creating specific properties.
When polymer chains are linked together. This limits the movement of individual chains (i.e. liquid cross linked would be a gel – more viscous/doesn’t flow as easily)
o use of plasticizers
Plasticizer “additive to increase the plasticity (ability to be shaped/formed) or fluidity (viscous/ ability to flow) of a material”
E.g. In concrete: Plasticizers soften the mix to make it easier to work with, but doesn’t affect the hardened product.
Plastics: Plasticizers soften the final product, making it more flexible.
Paste (usually) for filling gaps in material. When dried it can be sanded smooth and then finished.
Long strands of material that can be woven together.
Opposite to a catalyst, stops chemicals reacting with each other.
E.g. anti-oxidants – stop material oxidising
o Foamants. (not actually a word – error in spec maybe? )
Reducing moisture content of wood prior to use.
1. Wood is stacked in a kiln (wood has been “sticked” – sticks separate layers of wood to allow for air flow)
2. Ends of wood are painted (any paint nothing specific required)
3. Humidity of kiln increased – this makes sure that the wood is saturated before heating to even out the heating.
4. Heating – water drawn out by heating the wood. This is continued until desired moisture content achieved (generally 1-10%)
Air Dried (natural seasoning):
1. Wood is sticked/ painted as before
2. Wood placed outside under tarp.
3. Left for several months/years for moisture to be drawn out making wood usable.
**Need to know pros/cons of each**
When thin veneers are layered together to produce a shape.
The thin strips are flexible so curves can be produced.
1. Jig is made of the desired shape.
2. Thin strips are “laid up” in the jig and adhered together. Whilst glue drying, jig is pressed together (sash/G clamps) to squeeze out any air bubbles making a strong bond.
3.2 Product manufacture
Uses of ICT in the manufacture of products
The impact and advantages/disadvantages of ICT within the total manufacturing process:
o Electronic communications
o Electronic Data Interchange (EDI)
o Integrated Services Data Network (ISDN)
o Local Area Networks (LAN)
o Global networks (internet)
o video conferencing
o new communications technology
o Electronic information handling
o market analysis
o specification development
o Automated stock control
o ‘Just in time’.
o Production scheduling and production logistics.
o Flexible manufacturing systems
o Quick response manufacturing (QRM).
o Production control, for example monitoring quality using lasers and coordinate measurement machines (CMMs).
o Product marketing, distribution and retailing
o electronic point of sale
o Internet marketing.
Systems and control
Computer-Aided Design, Manufacture and Testing (CADMAT),
Computer-Integrated Manufacture (CIM), Flexible Manufacturing Systems (FMS) and their wider application in industry.
o Creative and technical design.
o Modelling and testing
o rapid prototyping (RPT)
o Virtual reality modelling.
o Production planning.
o Control of equipment, processes, quality and safety.
o Control of complex manufacturing processes.
o Integrated and concurrent manufacturing.
The use of block flow diagrams and flow process diagrams for representing simple and complex production systems including open/closed loop control, feedback and degrees of freedom.
The advantages and disadvantages of automation and its impact on employment, both local and global.
Complex automated systems using artificial intelligence (AI) and new technology.
3.3 Design in practice
The impact of values issues on product design, development and manufacture:
o Life Cycle Assessment (LCA).
Responsibilities of ‘developed’ countries in relation to production and the environment:
o Global sustainable development.
Environmental implications of the industrial age:
o the use of non-renewable raw materials and fossil fuels during the manufacturing process
o renewable sources of energy, energy conservation and the use of efficient manufacturing processes
o new technology and environmentally-friendly manufacturing processes
o importance of using sustainable technology
o Minimising waste production.
Economics of production
Economic factors in the production of one-off, batch, high-volume (mass) and continuous manufactured products, relating to, for example:
o sources, availability and costs of materials
o advantages of economies of scale of production
o the relationship between design, planning and production costs
o The material and manufacturing potential for a given design solution.
Advertising and marketing
The role of the media, including film, television, radio, video, newspapers and magazines, the internet, in marketing products.
The basic principles of marketing and associated concepts such as brand loyalty, competitive edge, consumer demand, lifestyle marketing, market pull, market share, price range, product proliferation, promotional gifts, target market groups.
Organisations that provide guidance, discrimination and approval:
o British Standards Institute (BSI)
o Advertising Standards Authority (ASA)
o Consumer magazines/TV programmes.
Relevant legislation on the rights of the consumer when purchasing goods:
o Statutory rights.
Thanks for this, it's helped keep me focused, I still can't help but feel ahhhh about the exam tomorrow. I feel like I can't remember anything !