This document discusses mechanical properties of materials and how understanding these properties helps with design and material selection. It defines key mechanical properties like hardness, toughness, elasticity, plasticity, malleability, durability, ductility, compressive strength and tensile strength. Various testing methods are also introduced, such as the Rockwell test for hardness and the Izod impact test for toughness. Real-life examples are provided to illustrate the importance of these material properties.

1. Creative
Mrs. Shamsa Aziz Alshehhi
Design&
Innovation

2. Materials
Section 1: Mechanical
Properties

3. Starter
Activity…

4. Identify the mechanical properties of different materials.
Learning
Outcomes
Understand how mechanical properties affect the
performance of materials.
Demonstrate real-life examples of why material
properties are important
Identify tensile strength, compressive strength, hardness,
toughness, elasticity, plasticity, ductility and malleability
Understand how you can test the mechanical properties of
materials.

5. 1
2
3
4
Because we understand how material behave
It helps to create our technological word.
Make decision about the design selection and use
of materials for specific applications.
Why do we need an understanding
of materials Page 15

6. Where do materials
come from

7. Wood
Steel+ironGunpowder
What materials
were used by
armies in the
wars?

8. Stone

9. What’s the
properties?
of various materials ?
What’s the
working
characteristic?

10. Shear
strength
Bending
strength
Torsion
strength
The ability To
withstand
Shear force
The ability to
withstand
bending
The ability to
Withstand
twisting
The ability to
Withstand breaking
When in tension
Types of force:-
Compressive
strength
Tensile
strength
The ability of
material
To withstand
compression
Activity

11. Activity
Shear
strength
Bending
strength
Torsion
strength
Compressive
strength
Tensile
strength

12. Activity 1.1
Page 17

13. Strength
Hardness
Toughness
Plasticity
/
Malleability
Durability
Ductility
There are 7 main mechanical properties
Elasticity

14. Hardness
The hardness of a material is its ability to resist
changing shape under force. Hard materials will
resist wear and tear well; they do not scratch or
dent easily. Hard materials, like marble, are used in
many Arabic homes. Why do you think that marble
is a suitable material for the stairs shown in fig.
1.10?

15. Testing for
Hardness
Engineers use a commonly used test called the
Rock Test to find the hardness of a material.

16. Toughness is the ability of a material to withstand
sudden impact before breaking.
Toughness

17. The larger the impact needed to fracture or break
of a material, the tougher the materials.
Testing for
Toughness

18. Testing for
Toughness
The Izod impact test is used to test the toughness
of a materials. The impact required to break the
test piece is used to find the toughness of the
material.

19. An ability of some materials to bend and flex when
a force is applied, and to return to shape and
Size when those forces are removed. For example,
an elastic band.
Elasticity

20. Malleability is the ability of a material to be
stretched or formed into another shape. It can then
hold that shape. Without breaking or fracturing.
Plasticity
/
Malleability

21. Durability
Durability is a material’s resistance to wear and
tear, and its resistance to corrosion and
deterioration. Durable materials are often used
outside where they might be exposed to the
weather.

22. Ductility indicates how well a material can be
stretched. A ductile material is one that changes
shape easily, under loading conditions, without
breaking.
Ductility
Steel and copper are ductile materials

23. Activity 1.3
Page 18

24. Open the book page 15

25. Open the book page 15

26. Do you
have any
question?