Corrosion Engineering Questions and Answers – Environments – Soil and Aerospace

«
»

This set of Corrosion Engineering Multiple Choice Questions & Answers (MCQs) focuses on “Environments – Soil and Aerospace”.

1. The corrosivity of soils varies over a wide range because of the variety of composition.
a) True
b) False
View Answer

Answer: a
Explanation: The corrosivity of a particular solution depends on its composition. So, the corrosivity of soils varies over a wide range because of the variety of composition.
advertisement

2. Which of the factors that affect the corrosiveness of soils?
a) Moisture
b) Acidity
c) Oxygen
d) Moisture, oxygen, acidity and stray currents
View Answer

Answer: d
Explanation: The factors that affect the corrosiveness of soils are moisture, oxygen, acidity, alkalinity, the permeability of air and water, stray currents, and biological organisms.

3. Which of the following is a good measure of corrosivity?
a) Thermal conduction
b) Electrical resistance
c) Thermal resistance
d) Mechanical properties
View Answer

Answer: b
Explanation: Electrical resistance is a good measure of corrosivity of a corrosive solution. Higher electrical resistance lowers the corrosivity of a solution. Dry soils are generally not very corrosive due to high electrical resistance.
Sanfoundry Certification Contest of the Month is Live. 100+ Subjects. Participate Now!
advertisement
advertisement

4. Which of the following type of corrosion is/are dominant due to backfills such as stones, cinders, wood, and metal?
a) Crevice corrosion
b) Pitting corrosion
c) Crevice and pitting corrosion
d) Neither crevice nor pitting corrosion
View Answer

Answer: c
Explanation: Crevice and pitting corrosion are the types of corrosion that dominate due to backfill such as stones, cinders, wood, and metal. Because these foreign particles result in the formation of crevices.

5. Which of the following is/are true regarding underground structures?
a) Ordinary carbon steels and cast irons are commonly used
b) Organic coatings can be used
c) Cathodic protection is applied to protect it from corrosion
d) Usually made of carbon steel and cast irons with or without organic coatings and supported by a cathodic protection system
View Answer

Answer: d
Explanation: Underground structures are usually made up of ordinary carbon steels and cast irons with or without organic coatings. These structures are also supported by a cathodic protection system to minimize corrosion.
advertisement

6. Which of the following type of corrosion is pre-dominate in underground corrosion?
a) Aerobic corrosion
b) Anaerobic corrosion
c) Aerobic and anaerobic corrosion
d) Neither aerobic nor anaerobic corrosion
View Answer

Answer: c
Explanation: The anaerobic type of attack is pre-dominate in underground corrosion. It is due to the non-availability of oxygen as it decreases with an increase in depth.

7. Which of the following areas of aircrafts face severe corrosion problems?
a) Fuel tank due to oxidizers and fuel
b) High-temperature corrosion in blast nozzles
c) The outer structure of the plane due to vacuum
d) Fuel tank due to oxidizers and fuel, high-temperature corrosion in blast nozzles
View Answer

Answer: d
Explanation: Fuel tank due to oxidizers and fuel and high-temperature corrosion in blast nozzles are the two areas that aerospace face severe corrosion problems. Whereas the hard vacuum of space does not cause corrosion.
advertisement

8. Which of the following materials is/are used for blast nozzles in aerospace?
a) Aluminum oxide and cemented tungsten carbide
b) Aluminum oxide cemented tungsten carbide and boron carbide
c) Cemented tungsten carbide only
d) Aluminum oxide and boron carbide
View Answer

Answer: b
Explanation: Aluminum oxide, cemented tungsten carbide, and boron carbide is the materials that are used for blast nozzles in aerospace. These materials are also known as refractory materials.

9. Which of the following is/are the prime considerations in space vehicles and aircraft?
a) High strength-weight ratios for materials and high ratios of payload to the vehicle’s weight
b) High strength-weight ratios for materials only
c) High ratios of payload to vehicles weight only
d) Neither high strength-weight ratios for materials nor high ratios of payload to the vehicle’s weight
View Answer

Answer: a
Explanation: High strength-weight ratio for materials and high ratios of payload to vehicle weight are the two prime considerations in space vehicles and aircraft.
advertisement

10. Rusting of high-strength steel due to resident water can cause stress-corrosion and hydrogen embrittlement.
a) False
b) True
View Answer

Answer: b
Explanation: Rusting of high-strength steel due to resident water can cause stress-corrosion and hydrogen embrittlement. Hydrogen charging of steel during electroplating can cause a brittle fracture.

11. Which of the following is/are the primary materials regarding the construction of aircraft?
a) Aluminum
b) Magnesium and titanium
c) Aluminum, magnesium, titanium, and iron
d) Titanium and magnesium
View Answer

Answer: c
Explanation: Aluminum, magnesium, titanium, and iron and their alloys are the primary materials regarding the construction of aircraft. These are selected based on a high strength-weight ratio for materials and high ratios of payload to vehicle weight.

12. Which of the following corrosion protective systems is/are included in aircraft industries?
a) Anodizing, cladding and conversion coatings
b) Anodizing and cathodic protection
c) Conversion coatings and anodizing
d) Cathodic protection only
View Answer

Answer: a
Explanation: Anodizing, cladding, and conversion coatings are the corrosive protective systems used in aircraft industries. Whereas cathodic protection cannot be used in the aircraft industry due to non-conductive electrolytes.

Sanfoundry Global Education & Learning Series – Corrosion Engineering.

To practice all areas of Corrosion Engineering, here is complete set of 1000+ Multiple Choice Questions and Answers.

advertisement
advertisement
Subscribe to our Newsletters (Subject-wise). Participate in the Sanfoundry Certification contest to get free Certificate of Merit. Join our social networks below and stay updated with latest contests, videos, internships and jobs!

Youtube | Telegram | LinkedIn | Instagram | Facebook | Twitter | Pinterest
Manish Bhojasia - Founder & CTO at Sanfoundry
Manish Bhojasia, a technology veteran with 20+ years @ Cisco & Wipro, is Founder and CTO at Sanfoundry. He lives in Bangalore, and focuses on development of Linux Kernel, SAN Technologies, Advanced C, Data Structures & Alogrithms. Stay connected with him at LinkedIn.

Subscribe to his free Masterclasses at Youtube & technical discussions at Telegram SanfoundryClasses.