Properties of materials

• What is the definition of hardness in wood?

  Hardness is the resistance of the wood to denting and wear.
• How does the direction of the wood grain affect hardness?

  Hardness varies depending on the direction of the wood grain.
• What test is used to measure the hardness of wood?

  The Janka hardness test is used to measure wood hardness.
• What does toughness in timber refer to?

  Toughness is the amount that timber can be bent without breaking or splitting.
• What affects the toughness of timber?

  Toughness is affected by the timber's internal cell structure.
• Which type of wood is generally tougher, hardwoods or softwoods?

  Most hardwoods are generally tougher than softwoods.
• What is the definition of durability in wood?

  Durability is the wood's ability to resist decay from exposure to the elements and attack from insects.
• Which type of wood is the most durable?

  Hardwoods such as oak are the most durable woods.
• How long can some types of bamboo last in terms of durability?

  Some types of bamboo have a durability of only a few months.
• What are the mechanical properties of materials?

  • Compressive strength: resistance to a pushing force
  • Tensile strength: resistance to a pulling force
  • Durability: resistance to wear, long lasting
  • Hardness: resistance to abrasion
  • Stiffness: resistance to bending and flexing
  • Elasticity: ability to stretch and return to shape
  • Impact resistance: resistance to knocks and impacts
  • Brittleness: hard but easily broken or shattered
  • Water resistance: resistance to water or moisture
  • Absorbency: ability to soak up moisture
• What are the manufacturing properties of materials?

  • Machinability: ability to be easily milled and drilled
  • Workability: ability to be placed and compacted
  • Ductility: ability to stretch, not break under stress or impact
  • Malleability: ability to be hammered, pressed or rolled without breaking
• What are other properties of materials?

  • Acoustic: acoustic absorption
  • Chemical: corrosion resistance
  • Electrical: conductivity, resistance
  • Thermal: conductivity, flash point
  • Magnetic: attractive to magnets
• What is the difference between malleability and ductility?

  Ductility relates to the ability of a material to stretch without damage, while malleability relates to deformation under compression.
• Why is it important to learn the properties of materials for design and technology?

  Understanding material properties helps explain why they are used to make certain products.
• What is the purpose of understanding properties in relation to exam questions?

  It helps to answer questions about individual products and their fitness for purpose.