functional requirements and material selection

• Functional Requirements


  Specific properties and characteristics needed for effective material performance.
• Material Characteristic


  Observable features of a material, can change depending on how the material is processed or combined with other materials.
• Colour or Texture

  Visual aspects important for aesthetic applications. E.g. steel can have a shiny polished finish, which doesn't affect the strength, but does add aesthetic appeal.
• Material Properties

  Inherent measurable features of a material.
• Physical Properties


  Measurable traits like density and conductivity. Categorised into 2 groups, physical, and mechanical properties.
• Density


  Mass per unit volume, indicating heaviness. Foam has a low density, and so is good for packaging fragile items.
• Electrical Conductivity


  Material's ability to conduct electricity. Metals are good conductors, hence why copper wires are used in electrical cables.
• Thermal Conductivity


  Efficiency of heat transfer through a material. Cooking pans need this, therefore are made of metal. Foam and fibreglass act as insulators, preventing thermal conductivity.
• Mechanical Properties


  Material traits affecting performance under stress.
• Strength


  Crucial for load-bearing components. The ability to withstand applied forces without deformation or failure. (Steel, used in bridges as it can support heavy loads while enduring harsh weather conditions)
• Durability


  Resistance to wear, fatigue, and degradation over time, ensuring longevity of the design. (Steel, used in bridges as is resistant to weathering)
• Hardness


  Resistance to indentation or scratching, impacting its resistance to wear and tear. (High carbon steel, saw blades)
• Rigidity


  Ability of a material to maintain shape under load. (Aluminium, high rigidly-to-weight ratio)
• Weight


  Critical consideration in many designs, esp. transportation or portable devices (carbon fibre, bikes, higher speed, less effort)
• Flexibility


  Capacity to bend or deform under stress without breaking. (PVC, hoses and tubing)
• Buoyancy


  Ability of a material to float or support weight in a liquid environment. (Styrofoam, a type of expanded polystyrene with excellent buoyancy, used in flotation devices)
• Environmental Stability


  Material performance under varying environmental conditions, including temperature, humidity and exposure to UV radiation. (Wood for outdoor furniture, teak and cedar)
• Aesthetic Appeal


  Visual attractiveness of a material in design.
• High-carbon Steel


  Material known for exceptional hardness in tools.
• Aluminium


  Lightweight metal with high rigidity for aerospace.
• Carbon Fibre Composites


  Lightweight materials ideal for bicycle frames.
• PVC


  Flexible material used in hoses and tubing.
• Styrofoam


  Material with excellent buoyancy for flotation devices.
• Teak and Cedar

  Wood types resistant to decay and moisture.
• What is crucial when selecting materials for manufacturing?

  Matching characteristics to manufacturing processes
• How does the scale of production affect material selection?

  It determines the efficiency and cost of processing
• In car manufacturing, what material is often chosen for body panels?

  Steel
• Why is carbon fibre preferred for high-end sports cars?

  It can be moulded into complex shapes
• What type of production runs 24/7 for large quantities of unchanged products?

  Continuous production
• What does mass production create?

  Large quantities of identical products
• How are smartphones produced?

  Using mass production and assembly lines
• What does batch production involve?

  Making products in groups with variations
• What is one-off production used for?

  Creating unique, custom products
• What are the suitable manufacturing processes for wasting?

  • Suitable for all production types
  • Manual tools for one-off production
  • CNC machine tools for mass production
• What processes are included in forming?

  • Rolling
  • Blanking
  • Press forming
  • Forging
• Which forming process is ideal for continuous production?

  Rolling
• What is the purpose of moulding in manufacturing?

  Shaping material in a mould
• What processes are included in moulding?

  • Injection moulding
  • Blow moulding
  • Rotational moulding
  • Vacuum forming
  • Sand casting
• What is casting in manufacturing?

  Pouring liquid material into a mould
• What is pressure die casting?

  Forcing molten metal into a mould