3.1.2 - notes


Materials:

  • 3.1.2 - performance characteristics of materials.

  • Papers & boards

  • Metals - non ferrous

  • Composites


METALS -

Non ferrous metals: Non-magnentic metals that do not have iron or a magnetic feild

  • Aluminium

Properties: Low density, high corrosion resistance, excellent thermal and electrical conductivity.

Melting point: 500 C - 650 C

Physical properties: Lightweight, good corrosion resistance, good electrical conductivity, good thermal conductivity, non magnetic and silvery-white colour.

Working properties: Easy to machine, easy to cast, highly malleable, highly ductile, easy to form and roll, can be welded.

Uses: Aircraft, window frames, cars, cans, electrical cables, kitchen equipment


  • Titanium

Properties: Strong, lightweight, low density, low conductivity, high corrosion resistance.

Melting point: 1,604 C - 1668 C

Physical properties: Very high strength-to-weight ratio, lightweight, excellent corrosion resistance, high melting point, non-magnetic, strong

Working properties: Can be forged, can be welded, can be machined although is hard, can be formed, good casting properties

Uses: Aircraft, aerospace components, medical implants, marine equipment, sporting equipment, chemical processing equipment


  • Copper

Properties: Good heat conductivity, good electrical conductivity, resistance to rust, good elasticity.

Melting point: 1,084 C - 1,357 C

Physical properties: Excellent electrical conductivity, excellent thermal conductivity, good corrosion resistance, high melting point, reddish brown colour, non magnetic

Working properties: High ductile, highly malleable, easy to draw into wire, easy to form, easy to solder and braze

Uses: Electrical wiring, plumbing, generators, radiators, heat exchangers


  • Tin

Properties: Soft, highly malleable, resists corrosion, melting point.

Melting point: 231.93 C

Physical properties: Low melting point, soft, good corrosion resistance, silvery-white colour, non magnetic

Working properties: Easy to cast, easy to form, highly malleable, ductile, easy to solder

Uses: Solder, food cans, electrical connections, protective coatings, alloys such as bronze


  • Gold

Properties: Malleable, ductile, high density, good electrical and thermal conductivity, high resistance to corrosion and oxidation.

Melting point: 1,064 C

Physical properties: Excellent corrosion resistance, does not tarnish easily, excellent electrical conductivity, high density, yellow/golden colour

Working properties: Extremely malleable, extremely ductile, easy to form, can be drawn into very fine wire, easy to machine

Uses: Jewellery, electronics, electrical connectors, specialist coatings, aerospace components.


  • Silver

Properties: Highest electrical conductivity, thermal conductivity, good resistance to oxidation.

Melting point: 961.8 C - 1234.95 C

Physical properties: Excellent electrical conductivity, high density, bright, shiny appearance, highly reflective

Working properties: Highly malleable, highly ductile, easy to form, easy to solder and braze, easy to machine

Uses: Jewellery, electrical contacts, electronics, solar panels, cutlery, mirrors


  • Zinc

Properties: High density, low melting point, resistant to corrosion, good electrical conductor.

Melting point: 419.5 - 420 C

Physical properties: Good corrosion resistance, low melting point, relatively brittle at room temperature, bluish-white/grey colour, good electrical conductivity

Working properties: Easy to cast, good die-casting properties, can be machined, can be formed when heated

Uses: Galvanising steel, roofing, gutters, die-casting components, making brass


Stock forms of Metal:

  • Sheet: Thin, flat, comes in different thicknesses and widths. Frequently used in manufacturing, automotive and construction sectors.

  • Plate: Thicker, flat rolled sheet, hot rolled, commonly used for structural components that need durability, machined into close tolerance components for electronics and aerospace equipment.

Bar: Solid, long and straight, widely used in machinery, centre, lathe and milling.

  • Flat

  • Square

  • Hexagonal

Tube: Long hollow metal shape.

  • Rectangular

  • Square

  • Hexagonal

  • Round

Structural:

  • H - Beam: Structural steel beam, cross section resembles ‘H’, used in Trailers, Tall steel buildings, Mezzanians and overhead cranes.

  • I - Beam: Cross section resembling ‘I’, used to support buildings, bridges and other structures, torsion and bending strength is good, ideal for load bearing applications.

  • Tee: Cross section resembling ‘T’, load bearing structural components, used in construction.

  • Channel: Cross sectional shape resembling ‘C’, long and continuous, applications require precision, used for window frames and similar things that require precision.

  • Angle (L): Cross sectional shape resembling ‘L’, used in a variety of applications such as, frames and masonry,




COMPOSITES -


Types of composites:

Fibre reinforced composites - Made up with resins and fibres, mixing fibers of glass or carbon allowing you to mould them into complex shapes, reinforcing them with fibres makes them stronger.

Particle based composites - Made up of small particles of materials, mixing smaller particles of sand with larger particles of cement and aggrate (stones), it gives us a strong, dense materials suitable for building structures.

Sheet based composites - Often available in large sheets, mixing wood fibres or thin slices of wood veneers with resins, to form large and stable sheets for furniture panels and interior construction.


Composit metals:

  • Carbon fibre reinforced plastic (CFRP):

  1. Carbon fibre is woven into a textile material and resins such as epoxy

  2. The epoxy is then cured

  3. Strong, best strength-to-weight ratio of all construction materials

  4. More expensive

  5. Improvement from fibre reinforced plastics

  6. Used in manufacture of expensive sports cars

  7. Expensive biking and motercycle frames

  8. Aerospace industry is often used as well


Advantages:

  • Lightweight - 5 times lighter than steel and 60% the weight of aluminium

  • Strong - high tensile strength and can withstand high loads and stress without the addition of extra weight.

  • Durable - resistant to corrosion and can survive extreme environmental conditions like humidity, rainfall, radiation and chemical exposure.

  • Fatigue resistant - Less likely to crack overtime.

  • Low thermal conductivity - the flow of heat can be controlled by rearraging the fibres.

  • X-ray transparent


Disadvantages:

  • Cost - its expensive, might be worth it when considering labor costs for heavier materials.

  • Environmental impact - Uses chemicals and consumes a lot of energy

  • Fire resistance - combustable and burns at a high temp compared to metals, would require fireproofing or flame retardants.

  • Design limitations - not suitable for applications that require complex moulding or forming processes depending on the complexity level.

  • Expertise requirements - Working with carbon fibre requires specialized knowledge.

  • Limited adhesives - its limited which can cause damage when its used under a large load.

  • Not recylable.


  • Glass reinforced plastic (GRP):

  1. Molten glass blown and spun which create fibres.

  2. Woven into sheets or mats.

  3. Strong and lightweight, highly versatile.

  4. Made from glass fibre and plastic resins.

  5. Laid in premade mould of shape you want to make.

  6. Resin is poured over fibres to make them into the shape of your mould.

  7. Then cured and removed leaving a thin, smooth shell.

  8. Used in products such as car bodywork, boat hulls, aeroplane wings.


Advantages:

  • Corrosion resistant - Resistant to harsh chemicals, wide pH range.

  • Low maintenance - Durable and can withstand weathering without corrosion or rot.

  • High strenght-to-weight ratio - Lightweight but strong, can be stronger than steel.

  • Anti-slip - Can be finished with it to reduce accidents.

  • Fire resistant - Can withstand high temps and prevent emitting toxic fumes.


Disadvantages:

  • Brittle - Can crack or break under sudden impact.

  • Limited temperature range - Typically usable between -40 C and 100 C.

  • Initial cost - Can be expensive.

  • Aging - Can degrade overtime due to UV rays, wind, rain, snow, and mechanical stress.


  • Tungsten Carbide:

  1. Dense, metal like compound

  2. Fine grey powder

  3. Contains equal parts of tungsten and carbon atoms

  4. About 3x stiffer than steel

  5. High melting point (2600 C)

  6. High impact resistance

  7. Compressive strength is higher than virtually all melted and cast/forged metals and alloys.

  8. Resistant to oxidation, doesn't dissolve in water, hydrochloric acid, or sulferic acid.

  9. Made by heating powdered tungsten with carbon black in the presence of hydrogen. The powder can be mixed with another metal, usually colbat and then pressed into the chosen shape.


Uses -

  • Cutting tools - saws, drills, chisels and milling tools.

  • Medical supplies - surgical and medical instruments, radiation shielding

  • Jewellery - rings, watches and pendants.


  • Aluminium composite board:

  1. Flat paneled

  2. Consists of two thin coils (aluminium coated) bonded to a non-aluminum core.

  3. Frequently used for external cladding, facades for buildings, insulation and signage.

  4. Durable, lightweight, easy to process, fire resistant, customisable, high strenghth, flatness.


Regulations:

  • Combustibility: boards have to be 18 metres talls (over), class A2 or have limited combustibility, 18 metre boards are banned in residential buildings.

  • Testing: entire panel needs to be thouroughly tested to meet all requirements.

  • IInstallation: must meet industry standards (LPS 1500 and LPS 1531)

  • Fire alarms and sprinklers: buildings containing them MUST contain them.

  • Evacuation plan: Building owners are responsible for this.


  • Concrete, including reinforced concrete:

Concrete:

  1. Mix of cement powder, sand, water and aggregates - dries hard.

  2. Cement becomes a water paste that hardens and bonds the aggregates together.

  3. Widely used in construction.

  4. High strength, durability, versatility and economy.

  5. Moulded into any shape and can mimic any surface texture.

  6. Can withstand many acids, water, fire and abrasion.

  7. Concrete can be finished to produce surfaces from glass smooth to coarsely textured, coloured with pigment or painted.

  8. Substantial strength in compression but is weak in tension.


Reinforced concrete:

  1. Steel is embedded in the concrete

  2. High tensile strength of steel and compressive strength of concrete work together.

  3. Allows for product to sustain stress.

  4. Used for construction on larger scale projects: bridges,dams, piers, tall buildings and stadiums.

  5. Commonly used in domestic construction.

  6. Footings and foundations of smaller houses.


  • Fibre cement:

  1. Versatile

  2. Made of cement reinforced with cellulose fibres.

  3. Mixture of: Cellulose fibre (filler and it grows from radiata pine trees), Cement (binding agent and made with limestone, clay and iron), Sand (Helps with weathering), Water (activates and hardens cement and dissolves wood pulp), small amount of other chemicals.

  4. Doesn't burn

  5. Water resistant

  6. Long lasting and resistant to rotting and warping.


  • Engineered wood:

  1. Glued laminated timber (Gulam)

  2. type of structural engineered wood.

  3. Made by layers of timber and durable moisture-resistant adhesives.

  4. Gulam (laminated beams) natural alternative to steel or concrete.

  5. Gulam is natural, economical, strong and attractive.

  6. Made by being glued together under pressure and heat with laminates of timber that have been accurately planed.

  7. Strong and stable.

  8. Usually spruce, can sometimes be redwood or siberian larch.

  9. Manufacturing, distributing and treating Gulam consume little energy compared to every other building material.



PAPERS & BOARDS -