Material Properties Flashcards
What is Viscosity?
The measure of a materials resistance to flow.
What are viscous stresses?
Ones resulting from relative viscosity of different fluid particles
Viscosity in a polymer melt will decrease with.
Increasing shear rate
Increasing temperature
What is the melting point?
The temperature at which a solid transitions to a liquid
What materials have definite melting points?
Pure materials
Generally what is the maximum operating temperature of a metal?
2/3 of Tm
What is thermal expansion?
The rate at which a material expands upon hearing.
Where is thermal expansion used in manufacturing?
Shrink fit components
What is ductility?
The measure of what plastic deformation that has been sustained at fracture.
What graph would ductility be plotted on?
Stress(y), strain(x)
What is hardness?
A measure of mad materials resistance to localised plastic deformation.
What are the main three test standards of hardness?
Brinell
Vickers
Rockwell
What is the generic testing procedure for hardness?
Apply a load via an indenter and then use the geometry of the indentation to quantify hardness.
What is fatigue?
The process of small crack growth due to cyclic loading.
What are the three stages of fatigue failure?
Crack initiation
Crack propagation
Final fracture
