Lecture 3 Flashcards
Stiffness
Ability to resist elastic deformation. The stiffer the material the smaller the deflection for a given load. Determined by Young’s Modulus
Tensile strength
The ability to withstand stretching loads without breaking
Compressive strength
The ability to withstand compressive loads without being crushed
Shear strength
The ability to withstand offset load without failure
*Increasing cross sections should give a higher strength
Hardness
A measure of resistance to indentation and scratching –> shows the wear resistance of the material
Toughness
Work required to propagate a crack through a material. A tough material resists breaking even with a growing crack. Also the ability of a material to withstand shock loads
Plasticity
A material which takes on a permanent plastic deformation when loaded beyond the plastic limit. Useful
- material to be worked into a shape
- absorbing energy
Ductility
Plastic deformation involving a tensile load. Allows a useful amount of plastic deformation to occur in tensile loading
Malleability
Plastic deformation occurring as a result of compressive loading
Brittleness
Shows little or no plastic deformation before fracture
Melting temperature (Tm)
The temperature at which solid transforms into liquid, only pure substances have unique melting points
Specific heat capacity (c)
The energy required to raise the temperature of 1 kg a material by 1 K
Thermal Conductivity (λ)
The ability of a material to transmit heat by conduction
Thermal Diffusivity (a)
Describes heat flow in a non-steady state
Thermal Expansion
A measure of the fraction of which a length of material changes when the temperature changes by a given amount
