STRESS AND STRAIN

SUB-MODULE UNIT: STRESS AND STRAIN

THEORY

Specific Objectives

By the end of the sub-module unit, the trainee should be able to:

1. define terms used in properties of materials
2. calculation of stress and strain
3. state Hooke’s law
4. describe the stress – strain relationship

Content

• Definitions

- plasticity

- elasticity

- stress

- modulus of elasticity

- bulk modulus

- yield modulus

• Calculations

- stress

- strain

• Stating Hooke’s law
• Describing the stress-strain relationship
• Sketching the stress-strain graph
• Modulus of rigidity
• Working stress and ultimate stress
• Factor of safety

PRACTICE

Specific Objectives

By the end of the sub-module unit, the trainee should be able to:

1. Set the apparatus for stress, strain experiment
2. Carry our experiment for stress and strain
3. Carry out tensile test for ferrous metals
4. Plot the stress strain graph
5. Calculate stress and strain

Content

• Apparatus
• Experiment for stress/strain
• Tabulate data
• Stress/strain graph

Competences

Ability to:

1. Carry our laboratory test on metals
2. Compute stress/strain results
3. Plot stress/strain graph
4. Interpret the test results
5. Calculate the stress/strain problems
6. Sketch and table the stress strain graphs

Suggested Teaching/Learning activities

• Demonstration
• Class exercises

Suggested Learning Resources

• Laboratory
• Text books
• Actual metals

Suggested Assessment Methods

• Practical exercise
• Written
• Assignments