ULTRASONIC TESTING (UT)
1. Which of the following
materials of the same alloy is most likely to produce the
greatest amount of sound
attenuation over a given distance?
(a) A hand forging
(b) A coarse grained casting
(c) An extrusion
(d) The attenuation is equal in
all materials
2. The ability to separate echos
from reflectors close together in depth is called:
(a) Resolution
(b) Attenuation
(c) Accuracy
(d) Sensitivity
3. Greater depth of penetration
in coarse grained material may be achieved using:
(a) More sweep delay
(b) Higher frequencies
(c) Less sweep delay
(d) Lower frequencies
4. Lower frequency transducers
produce:
(a) Deeper penetration, greater
attentuation and less beam spread
(b) Deeper penetration, less
attentuation and greater beam spread
(c) Greater beam spread but
higher sensitivity and resolution
(d) Less beam spread but lower
sensitivity and resolution
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5. Spurious indications might be
caused by which of the following?
(a) Mode conversion from beam
spread in a long specimen
(b) Surface waves generated
during straight beam testing
(c) A test piece with a smooth
machined surface
(d) All of the above
6. The portion of a test piece
which is represented by the CRT screen area from zero to
the rightmost edge of the initial
pulse is called:
(a) The dead zone
(b) The near field
(c) The near zone
(d) The far zone
7. The depth of penetration of
surface waves is approximately:
(a) One wavelength
(b) Three wavelengths
(c) 1/2 wavelength
(d) The total part thickness
8. An ultrasonic test using a
straight beam contact search unit is being conducted
through the thickness of a flat
part such as a plate. This test should detect:
(a) Laminar-type flaws with major
dimensions parallel to the rolled surface
(b) Transverse-type flaws with
major dimensions at right angles to the rolled
surface
(c) Radial flaws with major
dimensions along length but radially oriented to the
rolled surface
(d) None of the above
9. The first critical angle is
defined as the longitudinal wave incident angle which results
in:
(a) A refracted longitudinal wave
of ninety degrees
(b) A refracted shear wave of
ninety degrees
(c) Complete reflection of the
shear wave
(d) None of the above
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10.The number of complete waves
which pass a given point in a given period of time
(usually one second) is referred
to as the:
(a) Amplitude of a wave motion
(b) Pulse length of a wave motion
(c) Frequency of a wave motion
(d) Wavelength of a wave motion
11. The speed of sound in a given
material depends on:
(a) The specific acoustic
impedance of the material
(b) The acoustic impedance and
density of the material
(c) The density and elasticity of
the material
(d) The piezo-electric resistance
of the material
12. A screen pattern containing a
large number of low-level indications (often reffered to
as ‘hash’) could be caused by:
(a) A crack
(b) A large inclusion
(c) Coarse grained material
(d) Fine grained material
13. In an A scan presentation,
the horizontal base line represents the:
(a) Amount of refracted
ultrasonic sound energy
(b) Distance traveled by the
search unit
(c) Elapsed time or distance
(d) None of the above
14. An ultrasonic instrument
control which is used to expand or contract the horizontal
base line of an A scan display is
called:
(a) The sweep length or range
control
(b) The damping control
(c) The sweep delay
(d) The pulse length control
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15. In a basic ultrasonic test
pattern (A scan) for contact testing, the initial pulse (assume
no sweep delay is used):
(a) Is the high indication on the
extreme left side of the screen that represents the
entry surface of the inspected
part
(b) Is the first pulse that
occurs near the right side of the screen and represents the
opposite boundary of the
inspected part
(c) Is an indication that appears
and disappears during screening
(d) Is always the second pulse
from the left on the viewing screen
16. A term used in ultrasonics to
express the rate at which sound waves pass through
various substances is:
(a) Frequency
(b) Velocity
(c) Wave length
(d) Pulse length
17. Transducer focal lengths are
normally specified as:
(a) Distance in steel
(b) Distance in aluminium
(c) Distance in air
(d) Distance in water
18. The second critical angle is
defined as the longitudinal wave incident angle which
results in:
(a) A refracted longitudinal wave
of ninety degrees
(b) A refracted shear wave of
ninety degrees
(c) Complete reflection of the
sound beam
(d) None of the above
19. Spurious or nonrelevant
indications might be suspected if:
(a) Indications are unusually
consistent in amplitude and appearance
(b) There are strong indications
in localised areas
(c) The indications are localised
and repeatable
(d) None of the above
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20. A disadvantage of lithium
sulfate as a transducer material is that:
(a) It is an inefficient receiver
of ultrasonic energy
(b) It is soluble in water
(c) It is not piezo- electric
(d) It has extremely coarse grain
structure
21. An advantage of using a
ceramic transducer in search units is that:
(a) It is one of the most
efficient generators of ultrasonic energy
(b) It is one of the most
efficient receivers of ultrasonic energy
(c) It has a very low mechanical
impedance
(d) It can withstand temperatures
as high as 700oC
22. The three most common modes
of sound vibration are:
(a) Longitudinal, compressional,
and transverse waves
(b) Longitudinal, transverse and
rayleigh waves
(c) Transverse, longitudinal and
shear waves
(d) Transverse, shear waves and
rayleigh waves
23. A larger diameter crystal
results in:
(a) Greater beam spread
(b) Lower penetrating power
(c) Less beam spread
(d) Greater penetrating power
24. Entry surface resolution is a
characteristic of an ultrasonic testing system which
defines its ability to:
(a) Detect discontinuities
oriented in a direction parallel to the ultrasonic beam
(b) Detect discontinuities
located in the center of a forging containing a fine
metallurgical structure
(c) Detect minute surface
scratches
(d) Detect discontinuities
located just beneath the entry surface in the part being
tested
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25. Higher frequency transducers
produce which of the following?
(a) Greater beam spread,
sensitivity and resolution
(b) Greater sensitivity,
resolution and penetration
(c) Greater penetration,
attenuation and resolution
(d) Greater sensitivity,
resolution and attenuation
26. In immersion testing,
verification that the search unit is normal to a flat entry surface
is indicated by:
(a) Maximum reflection from the
entry surface
(b) Proper wavelength
(c) Maximum amplitude of the
initial pulse
(d) Elimination of water
multiples
27. Which of the following is
true?
(a) Velocity =
frequency/wavelength
(b) Frequency = velocity ×
wavelength
(c) Velocity =
wavelength/frequency
(d) Wavelength=velocity/frequency
28. Most commercial ultrasonic
testing is accomplished using frequencies between:
(a) 1 and 25 kHz
(b) 0.2 and 25 MHz
(c) 1 and 1 000 kHz
(d) 15 and 100 MHz
29. The longitudinal wave
incident angle which results in formation of a rayleigh wave is
called:
(a) Normal incidence
(b) The first critical angle
(c) The second critical angle
(d) Any angle above the first
critical angle
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30. An ultrasonic testing
technique in which the transducer element is not parallel to the
test surface is called:
(a) Angle beam testing
(b) Immersion testing
(c) Contact testing
(d) Through-transmission testing
31. In the same material, shear
wave velocity is:
(a) Approximately 1/2
longitudinal wave velocity
(b) Approximately twice
longitudinal wave velocity
(c) Approximately 1/4 longitudinal
wave velocity
(d) Approximately four times
longitudinal wave velocity
32. Another name for a
compression wave is a:
(a) Lamb wave
(b) Shear wave
(c) Longitudinal wave
(d) Transverse wave
33.Under most circumstances,
which of the following frequencies would result in the
best resolving power?
(a) 1 MHz
(b) 5 MHz
(c) 10 MHz
(d) 25 MHz
34.The most useful range of
incident longitudinal wave angles for ultrasonic testing is:
(a) Normal incidence to the first
critical angle
(b) First critical angle to the
second critical angle
(c) Second critical angle to the
third critical angle
(d) Above the third critical
angle
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35. Ultrasonic testing of
material where the search unit is in direct contact with the
material being tested may be:
(a) Straight beam testing
(b) Surface wave testing
(c) Angle beam testing
(d) All of the above
36. The echo on the cathode ray
tube (CRT) which represents the far boundary of the
material being tested is called:
(a) Hash
(b) The initial pulse
(c) The ‘main bang’
(d) The back wall echo
37. A standard block which can be
used to calibrate an instrument for an angle beam
range calibration is:
(a) Area-amplitude blocks
(b) Distance-amplitude blocks
(c) V1/A2 block
(d) Beam spread block
38. The ability to detect echos
from small reflectors is called:
(a) Resolution
(b) Attenuation
(c) Accuracy
(d) Sensitivity
39.When the motion of the
particles of a medium is parallel to the direction of
propagation, the wave being
transmitted is called a:
(a) Longitudinal wave
(b) Shear wave
(c) Surface wave
(d) Lamb wave
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40. In contact testing, the entry
surface indication is sometimes referred to as:
(a) The initial pulse
(b) The ‘main bang’ or
transmitter pulse
(c) Both (a) and (b)
(d) None of the above
41. A second name for Rayleigh
waves is:
(a) Shear waves
(b) Longitudinal waves
(c) Transverse waves
(d) Surface waves
42. Sound beam intensity
decreases expontentially with distance in the area called:
(a) The near field
(b) The far field
(c) The dead zone
(d) The delay line
43. A test method employing two
seperate search units on opposite surfaces of the
material being tested is called:
(a) Contact testing
(b) Surface wave testing
(c) Through-transmission testing
(d) Lamb wave testing
44. Which of the following is not
(!) a requirement of a couplant?
(a) Easy application
(b) Highly penetrating
(c) Harmless both to the test
piece and transducers
(d) Excludes all air between
transducer and test piece
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45. A plan view representation of
a test piece is produced by which of the following?
(a) A scan
(b) B scan
(c) C scan
(d) A time line display
46. A widening of the front
surface indication, when testing a rough surface, is caused by:
(a) Defects in the test piece
(b) A coarse grain structure
(c) A partial reflection of
ultrasonic beam side lobe energy
(d) Ultrasonic instrument
malfunction
47. When a vertical indication
has reached the maximum signal height which can be
displayed or viewed on the CRT of
an ultrasonic instrument, the indication is said to
have reached its:
(a) Distance-amplitude height
(b) Absorption level
(c) Vertical level
(d) Limit of resolution
48.A material used between the
face of a search unit and the test surface to permit or
improve the transmission of
ultrasonic vibrations from the search unit to the material
being tested is called:
(a) A wetting agent
(b) A couplant
(c) A acoustic transmitter
(d) A lubricant
49.When an ultrasonic beam passes
through the interface between two dissimilar
materials at an angle, a new
angle of sound travel is formed in the second material
due to:
(a) Attenuation of ultrasound
(b) Transmission of ultrasound
(c) Compression of ultrasound
(d) Refraction
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50. The velocity of sound waves
is primarily dependent on:
(a) The pulse length
(b) The frequency
(c) The material in which the
sound is being transmitted and the mode of vibration
(d) None of the above
51. Piezoelectric ability is the
property of a material to:
(a) Become electrically
conductive when heated above its critical temperature
(b) Generate sound when heated
above its critical temperature
(c) Vibrate at high frequency
when subjected to a temperature gradient
(d) Produce an electric current
when deformed and vice versa
52. The boundary between two
different materials which are in contact with each other is
called:
(a) A rarefactor
(b) A refractor
(c) An interface
(d) A marker
53. An ultrasonic insrument
control which is used to adjust the sharpness of the CRT
screen display is called:
(a) Astigmatism or focus
(b) Pulse repetition rate
(c) Pulse energy
(d) Gain
54. A disadvantage of using a low
frequency ultrasonic transducer is:
(a) It provides better
penetration in most materials
(b) It provides poorer
penetration in most materials
(c) It provides a smaller beam
angle and poorer resolving power
(d) It provides a larger beam
angle and poorer resolving power
195
55. As transducer crystal
thickness decreases:
(a) Transducer wavelength
increases
(b) Frequency decreases
(c) Frequency increases
(d) None of the above
56. On the area-amplitude
ultrasonic standard test blocks, the flat-bottomed holes in the
blocks are:
(a) All of the same diameter
(b) Different in diameter,
increasing by 1/64 inch increments from the No. 1 block
to the No. 8 block
(c) Largest in the No. 1 block
and smallest in the No. 8 block
(d) Drilled to different depths
from the front surface of the test block
57. An ultrasonic instrument
control which is used to expand or contract the horizontal
base line of an A scan display is
called:
(a) The sweep length or range
control
(b) The damping control
(c) The sweep delay
(d) The pulse length control
58. Greater depth of penetration
in coarse grained material may be achieved using:
(a) More sweep delay
(b) Higher frequencies
(c) Less sweep delay
(d) Lower frequencies
59. A disadvantage of using a low
frequency ultrasonic transducer is:
(a) It provides better
penetration in most materials
(b) It provides poorer
penetration in most materials
(c) It provides a smaller beam
angle and poorer resolving power
(d) It provides a larger beam
angle and poorer resolving power
196
60. A disadvantage of using a
high frequency ultrasonic transducer is:
(a) It provides a smaller beam
angle and better resolving power
(b) It provides a larger beam
angle and poorer resolving power
(c) It is scattered more by
coarse grained material
(d) It is scattered less by
coarse grained material
61. When a longitudinal wave
sound beam passes through an acoustic interface at some
angle other than zero degrees:
(a) Surface waves are generated
(b) Plate waves are generated
(c) Reflection, refraction and
mode conversion occur
(d) The first critical angle is
reached
62. The angle of a refracted
shear wave generated as a sound wave passes at an angle
through an acoustic interface is
depentant on:
(a) The acoustic impedances of
the materials on each side of the interface
(b) The frequency of the incident
sound wave
(c) The wavelength of the
incident sound wave
(d) The hardness of the materials
on each side of the interface
63. The purpose of the couplant
is to:
(a) Match impedances between the
transducer and test piece
(b) Absorb stray reflectors
(c) Clean the test piece so a
more efficient test may be continued
(d) Lock the ultrasonic scanner
into place prior to testing
64. Which of the following can be
a source of spurious ultrasonic signals?
(a) Surface roughness of the test
piece
(b) Mode conversion within the
test piece
(c) Shape or contour of the test
piece
(d) All of the above
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65. When a sound beam is
reflected:
(a) The angle of reflection is
found using Snell's law
(b) The angle of reflection
equals the angle of incidence
(c) All the sound energy is
reflected unless the acoustic impedanmce is zero
(d) Beam spread is decreased
66. Sound beam intensity
decreases expontentially with distance in the area called:
(a) The near field
(b) The far field
(c) The dead zone
(d) The delay line
67. The ability to detect echoes
from small reflectors is called:
(a) Resolution
(b) Attenuation
(c) Accuracy
(d) Sensitivity
68. The ability to separate
echoes from reflectors close together in depth is called:
(a) Resolution
(b) Attenuation
(c) Accuracy
(d) Sensitivity
69.Which of the following
transducer materials is the most efficient receiver of
ultrasonic energy?
(a) Lead metaniobate
(b) Quartz
(c) Lithium sulfate
(d) Barium titanate
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70. A display which shows the
initial pulse and the front surface echo superimposed
would be considered:
(a) An immersion test
(b) An A scan
(c) A contact test
(d) A B scan
71. A display which shows the
initial pulse and the front surface echo with a fairly wide
space between the two would be considered:
(a) An immersion test
(b) An A scan
(c) A contact test
(d) A B scan
72. When conducting an immersion
test, the water path distance must be controlled so
that:
(a) Spurious signals are not
created by surface waves on the test piece
(b) The (water path
distance)/(diameter) ratio does not result in asymmetric
standing waves
(c) The test piece discontinuity
indications appear between the first front and first
back surface echos
(d) The second front surface echo
does not appear on the CRT screen between the
first front and first back
surface echos
73. Bubblers and wheel
transducers are considered:
(a) Immersion techniques
(b) Modified immersion techniques
(c) Contact techniques
(d) Offset techniques
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