AME 4 Q3

1 / 5

What is the definition of tensile stress?

B) The internal resistance of a material to forces that pull it apart, calculated as the force applied per unit area.

A) The internal resistance of a material to forces that compress it, calculated as the force applied per unit area.

C) The internal resistance of a material to forces that twist or shear it, calculated as the force parallel to the surface divided by the area.

D) The internal resistance of a material to forces that bend it, calculated as the bending moment divided by the moment of inertia.

2 / 5

What is the definition of Young's modulus?

B) The ratio of the applied load to the maximum load a material can withstand, indicating the safety factor.

D) The ratio of compressive stress to compressive strain in a material, indicating its resistance to compressive forces.

A) The ratio of the shear stress to shear strain in a material, describing its rigidity against deformation.

C) The ratio of tensile stress to tensile strain in a material, describing its ability to resist deformation under tensile loading.

3 / 5

What is the definition of work hardening?

B) The increase in a material's hardness and strength as a result of plastic deformation, such as stretching or bending.

A) The process by which a material becomes softer and more ductile due to repeated deformation.

D) The process by which a material's grain structure becomes more uniform, improving its ductility and toughness.

C) The reduction in a material's hardness due to exposure to high temperatures over time.

4 / 5

What is ductile cast iron?

B) Cast iron that contains graphite flakes, making it brittle and unsuitable for applications requiring high impact resistance.

A) Cast iron that has high hardness but low tensile strength, used primarily for applications requiring resistance to wear.

D) Cast iron that has a high carbon content and is heat-treated to increase its brittleness, used for applications requiring high hardness.

C) Cast iron that has been alloyed with silicon and other elements to improve its ductility and tensile strength, allowing it to deform without breaking.

Correct Answer: C) Cast iron that has been alloyed with silicon and other elements to improve its ductility and tensile strength, allowing it to deform without breaking.

Explanation: Ductile cast iron (also known as ductile iron or nodular cast iron) is a type of cast iron that has been alloyed with elements like silicon and nickel to improve its ductility and tensile strength. The addition of these elements changes the structure of the graphite within the iron, forming nodules instead of flakes, which enhances the material’s ability to deform under stress without fracturing. This makes ductile cast iron suitable for applications where toughness and impact resistance are required.

Incorrect Options:

A) Cast iron that has high hardness but low tensile strength, used primarily for applications requiring resistance to wear.

Explanation: This option describes white cast iron, not ductile cast iron. White cast iron is known for its high hardness and wear resistance but has low tensile strength and is brittle, making it unsuitable for applications where ductility and impact resistance are needed.

B) Cast iron that contains graphite flakes, making it brittle and unsuitable for applications requiring high impact resistance.

Explanation: This describes gray cast iron, not ductile cast iron. Gray cast iron contains graphite flakes, which contribute to its machinability but also make it relatively brittle. This material is not suited for applications requiring high impact resistance or ductility.

D) Cast iron that has a high carbon content and is heat-treated to increase its brittleness, used for applications requiring high hardness.

Explanation: This option is incorrect because it describes white cast iron or a type of cast iron that has been heat-treated to increase hardness and brittleness. Ductile cast iron is specifically designed to be more flexible and less brittle, which is contrary to this description.

Correct Answer: C) Cast iron that has been alloyed with silicon and other elements to improve its ductility and tensile strength, allowing it to deform without breaking.

Explanation: Ductile cast iron (also known as ductile iron or nodular cast iron) is a type of cast iron that has been alloyed with elements like silicon and nickel to improve its ductility and tensile strength. The addition of these elements changes the structure of the graphite within the iron, forming nodules instead of flakes, which enhances the material’s ability to deform under stress without fracturing. This makes ductile cast iron suitable for applications where toughness and impact resistance are required.

Incorrect Options:

A) Cast iron that has high hardness but low tensile strength, used primarily for applications requiring resistance to wear.

Explanation: This option describes white cast iron, not ductile cast iron. White cast iron is known for its high hardness and wear resistance but has low tensile strength and is brittle, making it unsuitable for applications where ductility and impact resistance are needed.

B) Cast iron that contains graphite flakes, making it brittle and unsuitable for applications requiring high impact resistance.

Explanation: This describes gray cast iron, not ductile cast iron. Gray cast iron contains graphite flakes, which contribute to its machinability but also make it relatively brittle. This material is not suited for applications requiring high impact resistance or ductility.

D) Cast iron that has a high carbon content and is heat-treated to increase its brittleness, used for applications requiring high hardness.

Explanation: This option is incorrect because it describes white cast iron or a type of cast iron that has been heat-treated to increase hardness and brittleness. Ductile cast iron is specifically designed to be more flexible and less brittle, which is contrary to this description.

5 / 5

What is the definition of shear stress?

C) The internal resistance of a material to forces that twist or slide layers past each other, calculated as the force parallel to the surface divided by the area.

D) The internal resistance of a material to forces that bend it, calculated as the bending moment divided by the moment of inertia.

B) The internal resistance of a material to forces that compress it, calculated as the force applied per unit area.

A) The internal resistance of a material to forces that pull it apart, calculated as the force applied per unit area.

Your score is

Correct Answer: B) The internal resistance of a material to forces that pull it apart, calculated as the force applied per unit area.

Incorrect Options:

Correct Answer: B) The internal resistance of a material to forces that pull it apart, calculated as the force applied per unit area.

Incorrect Options:

Correct Answer: C) The ratio of tensile stress to tensile strain in a material, describing its ability to resist deformation under tensile loading.

Incorrect Options:

Correct Answer: C) The ratio of tensile stress to tensile strain in a material, describing its ability to resist deformation under tensile loading.

Incorrect Options:

Correct Answer: B) The increase in a material's hardness and strength as a result of plastic deformation, such as stretching or bending.

Incorrect Options:

Correct Answer: B) The increase in a material's hardness and strength as a result of plastic deformation, such as stretching or bending.

Incorrect Options:

Correct Answer: C) Cast iron that has been alloyed with silicon and other elements to improve its ductility and tensile strength, allowing it to deform without breaking.

Incorrect Options:

Correct Answer: C) Cast iron that has been alloyed with silicon and other elements to improve its ductility and tensile strength, allowing it to deform without breaking.

Incorrect Options:

Correct Answer: C) The internal resistance of a material to forces that twist or slide layers past each other, calculated as the force parallel to the surface divided by the area.

Incorrect Options:

Correct Answer: C) The internal resistance of a material to forces that twist or slide layers past each other, calculated as the force parallel to the surface divided by the area.

Incorrect Options: