Stress-Strain Relationship

What is the purpose of tension or compression test?

• Stability of the material

• Strength of material

What measurement needed prior to the tension & compression test?

• Initial x-sectional area

• The entire gauge length of the specimen

• The mass of the specimen

• Gauge length distance between two marks

What are the tools used to measure elongation?

• Inclinometer

• Micrometer

• Caliper

• Extensometer

Choose the correct order of Test & Compression test summary:

A) Machine will stretch the specimen until breaking point

B) Measure elongation to calculate the normal strain

C) Identify 2 small punch marks

D) Data of applied load P is recorded at frequent intervals

E) Specimens made into standard shape and size

F) Measure initial x-sectional area and gauge-length distance between 2 marks

• C - A - E - F - B - D

• C - F - E - A - D - B

• E - C - F - A - D - B

• F - A - B - C - E - D

How to determine nominal or engineering stress?

How to determine nominal or engineering strain?

• Directly from strain gauge reading

Choose the correct match.

• A : Necking

  B : Elastic region

  C : Yielding

  D : Strain hardening

• A : Elastic region

  B : Yielding

  C : Strain hardening

  D : Necking

• A : Strain hardening

  B : Necking

  C : Elastic region

  D : Yielding

• A : Elastic region

  B : Necking

  C : Strain hardening

  D : Yielding

Choose the correct match.

• A : Proportional limit

  B : Elastic limit/Yield stress

  C : Ultimate stress

  D : Fracture stress

  E : True fracture stress

• A : Proportional limit

  B : Elastic limit/Yield stress

  C : Fracture stress

  D : True Fracture stress

  E : Ultimate stress

• A : Proportional limit

  B : Elastic limit/Yield stress

  C : Ultimate stress

  D : True fracture stress

  E : Fracture stress

• A : Elastic limit/Yield stress

  B : Proportional limit

  C : Fracture stress

  D : True Fracture stress

  E : Ultimate stress

What happened to the specimen if the load is removed upon reaching its elastic limit?

• Specimen experience permanent deformation

• Specimen will break

• Specimen remains in elongation state

• Specimen will return to its original shape

Which statement describe 'yielding' region in stress-strain diagram?

• Specimen cross-sectional area is decreasing when specimen is elongating

• Specimen continue to elongate without any increase in load

• Specimen return to its original state when load is removed

• Specimen's x-sectional area is decreasing in localized region as its elongates