5 - Material Considerations Flashcards
Name the 6 factors that influence material choice.
Cost & Availability, Aesthetics, Sustainability, Social Footprint, Properties & Characteristics, Functional Performance.
What are the main factors of aesthetics to be considered?
Colour, form, feel, shape, touch & style
How might the choice of material impact the cost of a product?
People may be willing to pay more for it, stock forms may cause more waste, a new/rare material will be more expensive, bulk buying, may be difficult to work with
What are the 3 types of outsourcing?
Onshore, nearshore and offshore (global)
What are the benefits of outsourcing?
Cost efficient, businesses can focus on what they’re good at, access to specialists, global reach, enhanced productivity/efficiency
What are the negatives of outsourcing?
Dependant on suppliers (could mess up JIT), communication issues can occur, loss of work for local producers, larger producers may have power over smaller ones
What are mechanical properties?
How the material reacts to forces on it. These include strength, flexibility, fatigue limit and elasticity.
What are chemical properties?
How the material reacts & changes when in contact with other substances. These include hygroscopy (water absorption), corrosion resistance and reactivity.
What are physical properties?
The handling characteristics. These include density, conductivity, melting point, flammability and optical & acoustic properties.
What are manufacturing properties?
Processing properties; required for the material to change into a required shape. These include formability, machinability and fusibility (how easily it melts).
What social factors may need to be considered when choosing materials?
-Working conditions
-Maintaining traditional & local materials
-Inclusive design
-Emissions
What cultural factors may need to be considered when choosing materials?
-May remove local/cultural resource related to community traditions.
-May cause offence when inappropriately culturally appropriated.
Describe MDF & HDF
Wood fibres compressed into a solid board with 2 smooth faces. Often made from waste/recycled timbers.
What is the difference between MDF & HDF?
HDF is thinner, denser, stronger and more water resistant (but not much more!)
What are the main properties of MDF & HDF?
Easy to finish, absorbs moisture.
What are the uses of MDF & HDF?
Flat-pack furniture, model making, kitchens and desks.
How is block board made?
Timber battens are placed parallel to each other and glued between veneer panels at high pressure.
What are the characteristics of block board?
Attractive smooth surface, stronger & cheaper than plywood, durable but susceptible to moisture damage.
What are the uses of block board?
Table tops, furniture & load bearing shelves.
What is chipboard?
Chips of timber compressed into a board, which may be laminated with a range of coverings.
What are the properties of chipboard?
Strong, absorbs water, lightweight, cheap.
What are the uses of chipboard?
Flatpack furniture, kitchen cupboards, worktops.
Describe the structure of plywood.
An odd number of veneer layers are glued & compressed at 90° to each other.
What are the properties of plywood?
Good strength in all directions, no grain weakness, easy to cut, finish & paint.
What are the uses of plywood?
Structural work, desktops, indoor furniture and floorboards.
What is the difference between strength, hardness & toughness?
Hardness is resistance to wear, strength is resistance to external forces and toughness is resistance to sudden impacts.
What are the main differences between high and low-carbon steel?
High-carbon steel is stronger, more brittle, more expensive and harder. Both corrode without protection.
What are the uses of low carbon steel?
Nuts & bolts, bike frames, piping and bed frames.
What are the uses of high carbon steel?
Blades that maintain a sharp edge, high-speed tools and springs.
What % carbon is cast iron, low carbon and high carbon steel?
Low carbon: 0.25%
High carbon: 0.5-1.5%
Cast iron: 2-4%
What elements are in stainless steel?
Chrome (18%), nickel (8%), carbon and others.
What are the properties of stainless steel?
Tough, hard, ductile and corrosion resistant.
What are some common uses of stainless steel?
Cutlery, sinks and surgical instruments.
What are the characteristics of cast iron?
Cheaper and has a lower melting point than steel, hard and has a high compressive strength.
What are the characteristics of pine?
Light weight, resists shrinking/swelling, straight grain, knotty.
What are the uses of pine?
Utility poles, crates, flooring, paper, construction lumber.
What are the characteristics of douglas fir wood?
Slightly wavy grain, few knots, stable, accepts finishes well.
What are the uses of douglas fir?
Veneer, construction lumber, joinery, Christmas trees.
What are the characteristics of spruce wood?
Easy to work, straight grain, resistant to splitting, bad rot resistance.
What are the uses of spruce?
Indoor furniture, construction lumber, Christmas trees.
What are the characteristics of beech wood?
Close grain, tough, hard, durable & smooth.
What are the uses of beech?
Chairs, chopping boards, kitchen ware, turned bowls.
What are the characteristics of teak?
Coarse texture, straight grain, strong, hard, tough, rot resistant.
What are the uses of teak?
Boat building, veneer, furniture, exterior construction.
What are the characteristics of oak?
Good weather resistance, tough, durable, attractive grain, contains tannic acid (will corrode steel!)
What are the uses of oak?
Quality furniture, flooring, cladding, joinery.
State the properties of LDPE.
Tough, good chemical resistance, weatherproof, low rigidity, available in translucent form.
Give some uses of LDPE.
Squeezy detergent bottles, toys, carrier bags, bin liners, food packaging.
State the properties of HDPE.
Tough, good chemical resistance, weatherproof, available in translucent form.
Give some uses of HDPE.
Chemical drums, toys, kitchenware, long-life carrier bags, buckets, bowls.
State the properties of polypropylene (PP).
Tough, good chemical resistance, good fatigue resistance, available in translucent form.
Give some uses of polypropylene (PP).
Rope, folders, food containers, medical equipment.
Define fatigue resistance.
The ability of a material to resist cracking or fracture under repeated loading conditions.
State the properties of high-impact polystyrene (HIPS).
Hard, rigid, tough, available in translucent form.
Give some uses of high-impact polystyrene (HIPS).
Yoghurt pots, fridge linings, single-use cups, toilet seats.
State the properties of ABS.
Tough, hard, available in opaque.
Give some uses of ABS.
Rigid luggage, food mixers, handles, computer housings.
State the properties of PET.
Hard, translucent, good impact resistance.
Give some uses of PET.
Drink bottles, chocolate box liners.
State the properties of rigid polyvinyl chloride (uPVC).
Rigid, opaque, tough, hard, good weathering resistance, good chemical resistance.
Give some uses of uPVC.
Window frames, external doors, guttering, water service pipes, bank cards.
State the properties of flexible PVC.
Tough, flexible, available in translucent, good weathering resistance, good chemical resistance.
Give some uses of flexible PVC.
Hose pipes, cable insulation, medical tubing, inflatables, imitation leather.
State the properties of urea formaldehyde (UF).
Hard, heat resistant, good electrical insulator, brittle.
Give some uses of urea formaldehyde (UF).
Electrical fittings, adhesives.
State the properties of polyester resin.
Rigid, heat resistant, chemical resistant, brittle.
Give some uses of polyester resin.
Castings, car parts, used in lay-up process for glass reinforced plastic (GRP).
State the properties of epoxy resin.
Rigid, clear, hard, tough, chemical resistant.
Give some uses of epoxy resin.
Adhesives, surface coatings, encapsulation of electrical components, cardiac pacemakers, aerospace applications.
What is a composite material?
A material comprised of two or more different materials.
Give some examples of composite materials.
Carbon fibre-reinforced plastic (CFRP), glass-reinforced plastic (GRP).
State the properties of carbon fibre-reinforced plastic (CFRP) and glass-reinforced plastic (GRP).
Both are light, corrosion resistant, tough, hard, and have good compressive strength. GRP is cheaper.
Give some uses of carbon fibre-reinforced plastic (CFRP).
Bicycle frames, tennis racquets, fishing rods, racing car bodies, helmets.
Give some uses of glass-reinforced plastic (GRP).
Boat hulls, pond liners, kayak shells, sports car bodies, locomotive train cabs.
What is the definition of a modern material?
A material that is developed through the invention of new or improved processes.
Give some examples of modern materials.
E-textiles, super alloys, graphene, bioplastics, nanomaterials.
What are the features of e-textiles?
They contain conductive fibres.
How can e-textiles be used?
Textiles with smart colour displays, heating elements, monitoring the user’s heart rate.
What are the features of super alloys?
Significantly enhanced characteristics including strength, high temperature performance, corrosion/wear resistance.
How can super alloys be used?
Turbine blades, jet/ rocket engines, ships & submarines.
What are the features of graphene?
The world’s thinnest material, extremely light & strong, excellent conductor.
How can graphene be used?
Skis, low temperature li-Ion batteries, foldable phones. Biomedical products and membranes for water purification are in development.
What are the features of bioplastics?
They are made from plant-based sources like vegetable oil and corn starch.
How are bioplastics being used?
Alternatives to single-use plastic items, e.g. packaging, straws & cutlery, also phone cases and carpet fibres.
What are the features of nanomaterials?
A material’s properties are altered at the nanoscale, giving greater relative surface area, can improve properties e.g. strength, elasticity, conductivity.
How can nanomaterials be used?
Aerogel for foam insulation in buildings, clothing, refrigeration, aeroplane bodies.
What is a smart material?
A material whose physical properties change in response to a change in the environment.
