Topic 4.1 Flashcards
Electrical resistivity
The measure of a material’s ability to conduct or resist electricity
Thermal conductivity
A measure of how fast heat is conducted through a slab of material with a given temperature difference
Thermal expansion
A measure of the degree of increase in dimensions of a material when it is heated
Hardness
The resistance a material offers to penetration or scratching
Tensile Strength
The ability of a material to withstand pulling forces
Compressive strength
The ability of a material to withstand squashing forces
Stiffness
The resistance of an elastic body to deflection by an applied force (maintaining shape)
Toughness
The ability of a material to resist the propagation of cracks
Brittle
Low toughness; breaking into numerous sharp shards
Ductility
The ability of a material to be drawn or extruded into a wire or other extended shape
Malleability
The ability of a material to be shaped plastically
Elasticity
The ability of a material to reach its original shape when it is bent
Plasticity
The material deforms plastically and does not return to its original position
Stress in the member
The load on a structural member divided by its cross-sectional area
Strain
A measure of the relative change of shape it undergoes when subjected to a load
Young’s Modulus
Measure of stiffness of a given material (Stress:Strain)
Piezoelectricity
Piezoelectric materials give off a small electrical discharge when deformed
Shape Memory Alloys
Metals that exhibit pseudo-elasticity and shape memory effect due to rearrangement of the molecules in the material.
Shape memory effect
Allows severe deformation of a material, which can then be returned to its original shape by heating it
Pseudo-elasticity
The ability of a shape memory alloy to rearrange its molecules when there’s a load applied to it and reverses back to its original shape when load is decreased without changing its temperature.
Paramagnetism
A form of magnetism whereby certain materials are weakly attracted by an externally applied magnetic field.
Photochromicity
The ability of a material to change its colour when exposed to light.
Magneto-rheostatic material
A fluid that can undergo dramatic changes in its viscosity when exposed to a magnetic field and the effect is reversed when the field is removed.
Electro-rheostatic material
A fluid that can undergo dramatic changes in its viscosity when exposed to an electric field and the effect is reversed when the field is removed.
