This set of Advanced Machining Processes Multiple Choice Questions & Answers (MCQs) focuses on “CHM – Accuracy and Finish”.
1. Which of the following are necessary for best surface quality in Chemical milling?
a) Fine grain size and homogenous metallurgy
b) Coarse grain size and heterogeneous metallurgy
c) Fine grain size and heterogeneous metallurgy
d) Coarse grain size and homogenous metallurgy
Explanation: In CHM, for best surface quality, fine grain size and homogenous metallurgical work piece must be required.
2. Which of the following are the factors, on which, surface finish depends?
a) Grain size
b) Heat treatment
c) Induced stresses
d) All of the mentioned
Explanation: All the factors mentioned above, are responsible for different qualities of surface finish.
3. State whether following statement is true or false regarding surface finish in CHM.
“The surfaces, which are machined using Chemical milling, will have regular lay pattern.”
Explanation: In CHM, surfaces do not have regular lay pattern.
4. Which of the following defects cannot be altered or eliminated using CHM?
b) Surface imperfections
Explanation: Using CHM, surface imperfections cannot be eliminated.
5. Which type of etching rate, mentioned below, produces low surface roughness?
a) Very low
Explanation: In Chemical milling, high etching rate produces low surface roughness values and tolerances.
6. The depth of cut tolerances increases when machining ____ depths at high machining rates?
a) Very smaller
Explanation: In Chemical milling, tolerance increases when machining depth increases.
7. What is the value of etching rate, which can be achieved using Chemical milling?
a) 0.001 mm/min
b) 0.025 mm/min
c) 0.050 mm/min
d) 0.075 mm/min
Explanation: While we use Chemical milling etch rates of around 0.025 mm/min are achieved.
8. What are the tolerance values achieved in Chemical milling, which depend on work piece material and depth of cut?
a) ± 10%
b) ± 20%
c) ± 30%
d) ± 40%
Explanation: Tolerances of ± 10% of cut width are achieved using CHM.
9. For what value of machining depths, surface roughness sharply increases with depth of cut?
a) <100 µm
b) <200 µm
c) <300 µm
d) <400 µm
Explanation: For material depths <200 µm, surface roughness increases with depth of cut.
10. What is the value of surface roughness, which is generally obtained using Chemical milling?
a) 0.01 – 0.08 µm
b) 0.1 – 0.8 µm
c) 1 – 8 µm
d) 10 – 80 µm
Explanation: Surface roughness obtained when general conditions are applied, is between 0.1 – 0.8 µm.
11. What is the value of surface roughness, when special conditions are applied?
a) 0.001 – 0.025 µm
b) 0.025 – 0.05 µm
c) 0.05 – 0.075 µm
d) 0.075 – 0.1 µm
Explanation: Surface roughness obtained when special conditions are applied, is between 0.025 – 0.05 µm.
12. Which of the following can be easily removed using Chemical milling process?
a) TiO2 layer
b) Decarburized layer
c) Recast structure
d) All of the mentioned
Explanation: All the layers mentioned above, can be removed using Chemical milling.
13. State whether following statement is true or false about Chemical milling.
“CHM can also affect mechanical properties, if they differ from surface layer to base metal.”
Explanation: Chemical milling can affect the mechanical properties of the machined parts, if they are different at surface layers and base metal.
Sanfoundry Global Education & Learning Series – Advanced Machining.
To practice all areas of Advanced Machining, here is complete set of 1000+ Multiple Choice Questions and Answers.