Manufacturing Engineering Multiple Choice Questions on “Tool Wear and Failure”.
1. Thermal cracking of tools occurs at
a) Low temperature
b) High temperature
c) Low cutting speed
d) None of the mentioned
Answer: b
Clarification: At high temperature tool may lose its hardness property which results in failure of tool and this phenomenon is known as thermal cracking.
2. Mechanical chipping may occur in which of the following tool?
a) Diamond tool
b) Mild Steel tool
c) HSS tool
d) None of the mentioned
Answer: a
Clarification: Mechanical chipping occurs in brittle tools. Here diamond is a brittle material.
3. With the passage of time, there is loss in weight of tool, this phenomenon is known as:
a) Thermal cracking
b) Mechanical chipping
c) Softening
d) Gradual Wear
Answer: d
Clarification: Loss of weight of tool with respect to time is known as gradual wear.
4. Crater wear occurs at
a) Tool flank
b) Tool shank
c) Tool face
d) None of the mentioned
Answer: c
Clarification: Tool face is weaker for crater wear than shank or flank.
5. Which of the following is correct about crater wear?
a) Occurs more in soft tool
b) Occurs more hard tool
c) Occurs more in brittle tool
d) None of the mentioned
Answer: a
Clarification: Crater wear occurs in soft tools because their face gets eroded easily during flow of chips over the face.
6. Flank wear occurs at
a) Tool flank below cutting edge
b) Tool shank
c) Tool face
d) None of the mentioned
Answer: a
Clarification: Tool flank are generally subjected to flank wear due to rubbing action of tool. Cutting edge may be side cutting edge or end cutting edge.
7. What is the maximum allowed value of VB in mm for HSS tool used with cast iron work piece for rough machining?
a) 0.5
b) 1
c) 1.5
d) 2
Answer: d
Clarification: VB denotes the of wear land. Maximum 2mm of wear land is allowed in flank wear.
8. What is the maximum allowed value of VB in mm for HSS tool used with cast steel work piece for rough machining?
a) 0.5
b) 1
c) 1.5
d) 2
Answer: b
Clarification: VB denotes the of wear land. Maximum 1mm of wear land is allowed in flank wear.
9. What is the maximum allowed value of VB in mm for carbide tool used with cast iron work piece for a cutting condition of feed>0.3mm/rev?
a) 0.5
b) 1
c) 1.5
d) 2
Answer: d
Clarification: VB denotes the of wear land. Maximum 1mm of wear land is allowed in flank wear.
10. What is the maximum allowed value of VB in mm for carbide tool used with steel work piece for a cutting condition of feed>0.3mm/rev?
a) 0.5
b) 1
c) 1.7
d) 2
Answer: c
Clarification: VB denotes the of wear land. Maximum 1.7mm of wear land is allowed in flank wear.