Properties of Materials
Applied Science: BTEC Level 3 National Extended Diploma, topic 4.10.3
Tensile Strength
The tensile strength of a material is the amount of stress that can be withstood by the material in stretching it out. There are many different types of strength:
Yield strength
- The yield strength of a material is the stress value at the yield point.
- This is the -coordinate of the yield point.
-min,w_800.png)
Fracture strength
- The fracture strength of a material is the stress value at the fracture point.
- This is the -coordinate of the fracture point.
-min,w_800.png)
Ultimate tensile strength
- The ultimate tensile strength of a material is the maximum stress it can withstand at any point while the load is applied to extend it.
Brittle materials
- For brittle materials, the yield strength, fracture strength and the ultimate tensile strength are equal.
Behaviour of Materials
You need to know about the following ways that materials can behave under stress.
Malleability
- Malleable materials are easy to shape and can be hammered into a sheet.
- Gold is the most malleable metal.
Creep
- Creep is the gradual deformation of a material under constant tensile stress that is lower than the yield strength.
- Creep can be caused by the material deforming under its own weight.
- For example, the tiles used to make roofs can creep over time, leading to leaks.
Fatigue
- Fatigue is the deformation and ultimate fracture of a material due to a cyclic load that is placed upon it.
- A cyclic load is a load that repeats over time.
- Fatigue starts with a small crack that grows with each load cycle.
Test yourself on Properties of Materials
What is the maximum stress an object can withstand at any point while the load is applied to extend it called?
Which of the following is equal to the fracture stress of a material?
What is the gradual deformation of a material under constant tensile stress that is lower than the yield strength called?
Which type of load leads to fatigue in a material?