Mechanical pro Flashcards
What are the two main types of properties that materials have?
Mechanical properties and physical properties
What do mechanical properties relate to?
How a material performs when different forces are applied to it
List three examples of mechanical properties of materials.
- Strength
- Ductility
- Wear resistance
Define fatigue strength.
The maximum stress the material can withstand in a given number of cycles
What can lead to fracture under repeated or fluctuating stresses?
Fatigue
What is shear strength important for?
Applications like bolts or beams where direction and magnitude of stress are important
What does tensile strength refer to?
The amount of load a section of a material can withstand before it breaks
How is tensile strength measured?
In newtons (N) per square millimetre (megapascals or MPa), or pounds per square inch
What is yield strength?
The point after which a material under load will no longer return to its original position or shape
What is the difference between elastic and plastic deformation?
Elastic deformation returns to original shape, while plastic deformation does not
How is toughness measured?
Using the Charpy impact test
What does hardness represent in materials?
A material’s ability to resist permanent indentation
Name three methods used to measure hardness.
- Brinell
- Rockwell
- Vickers
Define ductility.
The ability of a material to deform without fracturing and retain the new shape when the load is removed
What is malleability?
A material’s ability to be formed without breaking under pressure
What does elasticity describe?
A material’s tendency to return to its original size and shape when a distorting force is removed
What is the converse of elasticity?
Plasticity
What is brittleness in materials?
Failure without undergoing any deformation on application of stress
Give examples of brittle materials.
- Ceramics
- Glass
- Cold metals
At what point do materials transition from elastic behavior to plastic behavior?
At the yield point
What does Young’s modulus measure?
The relationship between stress and strain in a material
