3.4.2 Materials Flashcards
Density
Mass per unit Volume
Tensile Stress
Force per unit Area
Tensile Strain
The extension per initial unit length following the tensile stress
Young’s Modulus
Measure of stiffness
Accounts for materials dimensions
Hooke’s Law
The force applied to a spring is directly proportional to the extension of the spring up to the limit of proportionality
Elastic Limit
Once the force passes it the material will be permanently stretched. After the unloading path is different
Limit of proportionality
The point where after Hooke’s Law no longer applies
Stress-Strain graph points
1) Limit of Proportionality
2) Elastic Limit
3) Yield Point
4) Ultimate Tensile Stress
5) Breaking Point
6) Permanent Strain
Yield Point
With no added stress the strain keeps increasing
Keeps getting longer with no force
Ultimate Tensile Stress
Most stress that can be applied before breaking
Max Force
Stress-Strain Large Gradient
More Stiff
Stress-Strain Large Area
More Tough
More energy required to break
