Manufacturing Engineering Multiple Choice Questions on “Machinability”.
1. The specific cutting energy used for establishing the machinability of the metal depends upon its
a) coefficient of friction
b) micro-structure
c) work hardening characteristics
d) all of the mentioned
Answer: d
Clarification: None
2. For machining a mild steel workpiece using carbide tool, the maximum material will be removed at a temperature of
a) 500
b) 1000
c) 1750
d) 2750
Answer: b
Clarification: None
3. For machining a mild steel workpiece by a high speed steel tool, the average cutting speed is
a) 5 m/min
b) 10 m/ min
c) 15 m/min
d) 30 m/min
Answer: d
Clarification: For machining a cast iron workpiece by a high speed steel tool, the average cutting speed is 22 m/min and for a mild steel is 30 m/min.
4. For machining a cast iron workpiece by a high speed steel tool, the average cutting speed is
a) 10 m/min
b) 15 m/min
c) 22 m/min
d) 30 m/min
Answer: c
Clarification: For machining a cast iron workpiece by a high speed steel tool, the average cutting speed is 22 m/min and for a mild steel is 30 m/min.
5. The machining of titanium is difficult due to
a) high thermal conductivity of titanium
b) chemical reaction between tool and work
c) low tool-chip contact area
d) none of the mentioned
Answer: c
Clarification: None
6. The factor considered for evaluation of maintainability is
a) cutting forces and power consumption
b) tool life
c) type of chips and shear angle
d) all of the mentioned
Answer: d
Clarification: None
7. In machining metals, chips break due to _____________ of work material.
a) toughness
b) ductility
c) elasticity
d) work hardening
Answer: d
Clarification: None
8. In machining metals, surface roughness is due to
a) feed marks or ridges left by the cutting tool
b) fragment of built up edge on the machined surface
c) cutting tool vibrations
d) all of the mentioned
Answer: d
Clarification: None
9. In machining soft materials, a tool with a negative relief angle is used
a) True
b) False
Answer: a
Clarification: None
10. The tool material, for faster machining, should have
a) wear resistance
b) red hardness
c) toughness
d) all of the mentioned
Answer: d
Clarification: None