Corrosion - Mechanical Engineering (MCQ) questions and answers

1)   Which type of chemical reaction is observed at cathode, in electrochemical corrosion?

a. Oxidation reaction
b. Peretectic reaction
c. Reduction reaction
d. None of the above
Answer  Explanation 

ANSWER: Reduction reaction

Explanation:
No explanation is available for this question!


2)   Chemical action during corrosion converts metal into metallic component as ________

a. hydroxide
b. oxide
c. sulphate
d. all of the above
Answer  Explanation 

ANSWER: all of the above

Explanation:
No explanation is available for this question!


3)   What is meant by corrosion?

a. Chemical reaction between anode, cathode and electrolyte, which leads to loss of metal
b. Deterioration of metals due to reaction with its environment
c. Both a. and b.
d. None of the above
Answer  Explanation 

ANSWER: Both a. and b.

Explanation:
No explanation is available for this question!


4)   Which of the following corrosions are caused due to velocity of fluid flow in pipes?

a. Bimetal corrosion
b. Cavitation corrosion
c. Galvanic corrosion
d. Intergranular corrosion
Answer  Explanation 

ANSWER: Cavitation corrosion

Explanation:
No explanation is available for this question!


5)   Corrosion fatigue is a combined effect of _____

a. Corrosive environment and mechanical stresses
b. Cyclic loading and corrosion
c. Velocity and mechanical stresses
d. None of the above
Answer  Explanation 

ANSWER: Cyclic loading and corrosion

Explanation:
No explanation is available for this question!


6)   Which element precipitates at the grain boundaries, when austenitic stainless steel is heated at 900 oC?

a. Aluminium carbide
b. Chromium carbide
c. Magnesium carbide
d. Molybdenum carbide
Answer  Explanation 

ANSWER: Chromium carbide

Explanation:
No explanation is available for this question!


7)   The intergranular corrosion can be prevented using ______

a. stabilized grade of stainless steel containing titanium and niobium as an alloying element
b. low carbon grade of stainless steel
c. both a. and b.
d. none of the above
Answer  Explanation 

ANSWER: both a. and b.

Explanation:
No explanation is available for this question!


8)   Knife Line Attack is a type of _______

a. bimetal corrosion
b. intergranular corrosion
c. localized corrosion
d. uniform corrosion
Answer  Explanation 

ANSWER: intergranular corrosion

Explanation:
No explanation is available for this question!


9)   The erosion corrosion can be controlled by _______

a. increasing the flow velocity through pipes
b. increasing temperature of fluid
c. minimizing turbulence
d. all of the above
Answer  Explanation 

ANSWER: minimizing turbulence

Explanation:
No explanation is available for this question!


10)   Which of the following methods is not used to coat metallic elements to prevent corrosion?

a. Electroplating
b. Metal cladding
c. Metal spraying
d. None of the above
Answer  Explanation 

ANSWER: None of the above

Explanation:
No explanation is available for this question!


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