materials Flashcards
Whats hookes law
The extension is proportional to the force applied provided the limit of proportionality is not excedeed.
What is elastic deformation
If a material is deformed but can return to its original shape or size once the deforming force/stress has been removed.
What is plastic deformation
If a material is deformed by a stress it cannot go back to its original shape and size even afterdeforming stress is removed.
Whats Fracture
point at which material will break
What is stress
Stress is a measurement of how much pressure a material can withstand without undergoing physical change
formula for
what is Tensile strength
Tensile strength the amount of stress a material can be put under before it fractures.
what is Yield strength
Yield strength is the amount of stress a material can take before it deforms permanently.
what is Strain
Strain is a ratio between the original length of the material and the amount it has extended by.
formula for strain
Strain = extension/original length
whats young modulus
ratio of stress over strain gives us the Young modulus.
how stiff a spring is
formula for young modulus
Stress and Strain
define ductile
Materials that have a large plastic region (drawn out into wires)
define Brittle
Material that distorts very little even when subject to a large stress and does not exhibit plastic deformation.
define polymeric
Material made of many smaller molecules bonded together. Exhibit very large strains
