© Mikell P. Groover 2012
Chapter 25 NONTRADITIONAL MACHINING AND THERMAL CUTTING
PROCESSES
Multiple Choice Quiz
There are 26 correct answers in this multiple choice quiz (some questions have multiple answers
that are correct). To achieve a perfect score on the quiz, all correct answers must be given. Each
correct answer is worth 1 point. Each omitted answer or wrong answer reduces the score by 1
point. Percentage score on the quiz is based on the total number of correct answers.
25.1
Which of the following processes use mechanical energy as the principal energy source
(three correct answers): (a) electrochemical grinding, (b) laser beam machining, (c)
conventional milling, (d) ultrasonic machining, (e) water jet cutting, and (f) wire EDM?
25.2
Ultrasonic machining can be used to machine both metallic and nonmetallic materials: (a)
true or (b) false?
25.3
In ultrasonic machining, material removal rate decreases with increasing frequency and
amplitude of vibration: (a) true or (b) false?
25.4
In water jet cutting and abrasive water jet cutting, the separation between the nozzle
opening and the work surface is called which one of the following: (a) gap, (b) gap size, (c)
orifice, (d) overcut, or (e) standoff distance?
25.5
In abrasive water jet cutting, the abrasive particles are added to the water stream: (a) after it
exits the nozzle, (b) before it enters the pumping unit, (c) just before it enters the nozzle, or
(d) while it is in the nozzle?
25.6
Abrasive water jet cutting and abrasive jet machining are two different names for the same
process: (a) true or (b) false?
25.7
Disadvantages of electrochemical machining include which of the following (two best
answers): (a) disposing of the electrolyte sludge created in the process, (b) high cost of
electrical power, (c) high tool wear, (d) low metal removal rates for hard metals, and (e)
surface damage to work?
25.8
The metal removal rate in electric discharge machining depends on which of the following
variables and properties (two correct answers): (a) discharge current, (b) hardness of the
work metal, (c) melting temperature of the work metal, and (d) tensile strength of the work
metal?
25.9
The liquid used to create the discharge path between the tool and the work in electric
discharge machining is called which one of the following: (a) dielectric fluid or (b)
electrolyte?
25.10 Applications of electron beam machining are limited to metallic work materials because the
work must be electrically conductive: (a) true or (b) false?
25.11 Which one of the following is closest to the temperatures used in plasma arc cutting: (a)
2750C (5000F), (b) 5500C (10,000F), (c) 8300C (15,000F), (d) 11,000C (20,000F),
or (e) 16,500C (30,000F)?
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students enrolled in courses for which the textbook has been adopted. Any other reproduction or translation of this work beyond that permitted
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© Mikell P. Groover 2012
25.12 Which one of the following fuels used in flame cutting produces the highest flame
temperatures: (a) acetylene, (b) methylacetylene-propadiene, (c) propane, or (d)
propylene?
25.13 Chemical milling is used in which of the following applications (two best answers): (a)
drilling holes with high depth-to-diameter ratio, (b) making intricate patterns in thin sheet
metal, (c) removing material to make shallow pockets in metal, (d) removing metal from
aircraft wing panels, and (e) cutting of plastic sheets?
25.14 The etch factor in chemical machining is equal to which one of the following: (a) CIt, (b)
d/u, or (c) u/d; where C = specific removal rate, d = depth of cut, I = current, t = time, and u
= undercut?
25.15 Of the following processes, which one is noted for the highest material removal rates: (a)
electric discharge machining, (b) electrochemical machining, (c) laser beam machining, (d)
oxyfuel cutting, (e) plasma arc cutting, (f) ultrasonic machining, or (g) water jet cutting?
25.16 Which one of the following processes would be appropriate to drill a hole with a square
cross section, 6 mm (0.25 in) on a side and 25 mm (1 in) deep in a steel workpiece: (a)
abrasive jet machining, (b) chemical milling, (c) EDM, (d) laser beam machining, (e)
oxyfuel cutting, (f) water jet cutting, or (g) wire EDM?
25.17 Which of the following processes would be appropriate for cutting a narrow slot, less than
0.40 mm (0.016 in) wide, in a 3/8-in-thick sheet of fiber-reinforced plastic that is 9.5 mm
(3/8 in) thick (two best answers): (a) abrasive jet machining, (b) chemical milling, (c)
EDM, (d) laser beam machining, (e) oxyfuel cutting, (f) water jet cutting, and (g) wire
EDM?
25.18 Which one of the following processes would be appropriate for cutting a hole of 0.075 mm
(0.003 in) diameter through a plate of aluminum that is 1.6 mm (1/16 in) thick: (a) abrasive
jet machining, (b) chemical milling, (c) EDM, (d) laser beam machining, (e) oxyfuel
cutting, (f) water jet cutting, and (g) wire EDM?
25.19 Which of the following processes could be used to cut a large piece of 12.7-mm (0.50-in)
plate steel into two sections (two best answers): (a) abrasive jet machining, (b) chemical
milling, (c) EDM, (d) laser beam machining, (e) oxyfuel cutting, (f) water jet cutting, and
(g) wire EDM?
Excerpts from this work may be reproduced by instructors for distribution on a not-for-profit basis for testing or instructional purposes only to
students enrolled in courses for which the textbook has been adopted. Any other reproduction or translation of this work beyond that permitted
by Sections 107 or 108 of the 1976 United States Copyright Act without the permission of the copyright owner is unlawful.