1. Which of the following is NOT a type of wear mechanism?
a) Adhesive wear
b) Corrosive wear
c) Abrasive wear
d) Impact wear
Answer: b) Corrosive wear
Explanation: Corrosive wear is not a type of wear mechanism; it refers to the combined action of corrosion and mechanical wear.
2. Two-body wear occurs when:
a) A third particle intervenes between the surfaces
b) Surfaces slide against each other with no intermediate particles
c) Surface fatigue leads to wear
d) Lubricants prevent direct contact between surfaces
Answer: b) Surfaces slide against each other with no intermediate particles
Explanation: Two-body wear involves direct contact and sliding between two surfaces with no intervening third body.
3. Fretting wear is characterized by:
a) Intense impact forces
b) Abrasive particles between surfaces
c) Small amplitude oscillatory motion
d) Corrosive environments
Answer: c) Small amplitude oscillatory motion
Explanation: Fretting wear occurs due to repeated small-scale oscillatory motion between two surfaces in contact.
4. The wear rate in abrasive wear is primarily influenced by:
a) Relative velocity between surfaces
b) Hardness of the softer material
c) Presence of lubricants
d) Surface roughness
Answer: b) Hardness of the softer material
Explanation: In abrasive wear, the hardness of the softer material determines the wear rate as it dictates the resistance to abrasion.
5. What is the primary cause of adhesive wear?
a) Surface fatigue
b) Chemical reactions between surfaces
c) Bonding and tearing of material from one surface to another
d) Impact of foreign particles
Answer: c) Bonding and tearing of material from one surface to another
Explanation: Adhesive wear occurs due to the bonding and subsequent tearing of material from one surface to another during relative motion.
6. Which wear mechanism is associated with high-velocity impacts?
a) Abrasive wear
b) Impact wear
c) Adhesive wear
d) Fretting wear
Answer: b) Impact wear
Explanation: Impact wear results from high-velocity impacts between two surfaces, causing material removal.
7. Cavitation wear is caused by:
a) Corrosive substances
b) Oscillatory motion
c) Formation and collapse of vapor bubbles
d) High-temperature environments
Answer: c) Formation and collapse of vapor bubbles
Explanation: Cavitation wear occurs due to the formation and collapse of vapor bubbles in a fluid medium, leading to surface damage.
8. Which type of wear is predominant in metal cutting tools?
a) Abrasive wear
b) Adhesive wear
c) Impact wear
d) Fretting wear
Answer: a) Abrasive wear
Explanation: Metal cutting tools experience abrasive wear due to the presence of hard particles in the workpiece material.
9. Surface fatigue is caused by:
a) Continuous sliding motion
b) High-temperature exposure
c) Repeated cyclic loading
d) Chemical reactions with the environment
Answer: c) Repeated cyclic loading
Explanation: Surface fatigue results from repeated cyclic loading, leading to crack initiation and propagation on the surface.
10. Which factor is critical in preventing corrosion wear?
a) Surface roughness
b) Lubricant viscosity
c) Chemical composition of materials
d) Mechanical properties of materials
Answer: c) Chemical composition of materials
Explanation: The chemical composition of materials plays a critical role in preventing corrosion wear by providing resistance to chemical attack.