1. Mechanical Constraints

2. 5 constraints (CTTDS)
Compression
A crushing or squeezing force.

3. 5 constraints (CTTDS)
Compression
A crushing or squeezing force.

4. 5 constraints (CTTDS)
Tension
A pulling or stretching force.

5. 5 constraints (CTTDS)
Tension
A pulling or stretching force.

6. 5 constraints (CTTDS)
Torsion
A twisting force.

7. 5 constraints (CTTDS)
Torsion
A twisting force.

8. 5 constraints (CTTDS)
Deflection
A bending force.

9. 5 constraints (CTTDS)
Deflection
A bending force.

10. 5 constraints (CTTDS)
Shearing
A cutting force.

11. 5 constraints (CTTDS)
Shearing
A cutting force.

12. 3 Types of Deformations (EPF)
Elastic
A temporary change in shape. The object returns to its original shape when the stress is removed.

13. 3 Types of Deformations (EPF)
Plastic
A permanent change in shape, even when the constraint is removed.

14. 3 Types of Deformations (EPF)
Fracture
The constraint causes the object to break

15. Mechanical Properties
Which object would be better for a tug of war?

16. Mechanical Properties
Which object would be better for a tug of war?

17. Mechanical Properties
Which object would be better for a tug of war?

18. Mechanical Properties
Which object would be better for a tug of war?

19. Mechanical Properties
Which object would be better for a tug of war?
Different materials react in different ways to constraints. We need to choose materials with certain properties.

20. Mechanical Properties
Hardness This is a material’s ability to resist denting and scratching.

21. Mechanical Properties
Ductility The ability of an object to stretch without breaking.

22. Mechanical Properties
Elasticity The ability of an object to return to its original shape.

23. Mechanical Properties
Malleability The ability of a material to bend without breaking.

24. Mechanical Properties
Resilience A material’s ability to resist shock.

25. Mechanical Properties
Stiffness A material’s ability to maintain its shape.

26. Mechanical Properties
Tensile Strength A material’s ability to resist tension without breaking or deforming.

27. Summary 5 Constraints 3 Deformations 7 Properties
(CTTDS) (EPF) (HDEMRSTS) 6 7