Ut Lvl 1 Flashcards
The main advantage of the Rompas or DIN block (IIW block 2) is
a) increased number of characteristics that can be tested
b) greater ranges can be tested
c) improved sensitivity calibrations
d) portability
d) portability
In ultrasonic testing, one of the best means of conveying a large quantity of information about a test piece is by
a) B-scans
b) C-scans
c) ultrasonic imaging
d) the tandem probe technique
c) ultrasonic imaging
Decreased damping on a piezoelectric element results in
a) reduced ringing time
b) increased resolution
c) decreased sensitivity
d) all of the above
d) all of the above
Information obtained about the exit point and refracted angle of an angle beam probe
a) is qualitative only
b) must be check periodically since the probe is subject to wear
c) is fixed by the manufacture
d) none of the above
b) must be check periodically since the probe is subject to wear
When a piezoelectric material has a voltage applied to it
a) eddy currents are generated
b) flux leakage can be used for testing
c) mechanical deformation occurs
d) all of the above
c) mechanical deformation occurs
In practical ultrasonic testing, mirror surfaces can be used with sound beams to
a) image flaws
b) reach points of difficult access
c) reduce scatter
d) reduce short wave dispersion effects
b) reach points of difficult access
The usual form of denoting acoustic impedance is
a) Z
b) A
c) I
d) R
a) Z
Difficulties determining exact lateral location and relative size of a flat reflector in the near zone result from
a) the dead zone
b) ring down
c) multiple maxima and minima
d) absorption
c) multiple maxima and minima
Focusing of ultrasound is accomplished by
a) curved piezoelectric crystals
b) lenses
c) both a and b
d) none of the above
c) both a and b
If the beam from an unfocused probe strikes a convex steel surface from water with normal incidence it will
a) increase beam spread
b) decrease beam spread
c) focus the beam
d) none of the above
a) increase beam spread
The incident angle at which the transmitted longitudinal wave first ceases to exist in the diffracting medium is called the
a) longitudinal angle
b) short angle
c) first critical angle
d) second critical angle
c) first critical angle
When using angle beams (transverse waves) for ultrasonic testing, the position of a flaw signal on the timebase can be
calibrated for
a) sound path length
b) stand-off distance
c) depth of defect
d) all of the above
d) all of the above
Mode conversion in ultrasonics occurs at
a) defects
b) corner reflectors
c) only free boundaries
d) all boundaries
d) all boundaries
Attenuation is not a result of
a) beam geometry
b) scatter
c) bond breaking at the molecular level
d) absorption
a) beam geometry
In ultrasonic testing, a wave pulse contains
a) a single well defined frequency
b) a range of frequencies
c) two full cycles
d) only positive going waves
b) a range of frequencies
In an A-scan presentation, the indication of the instant at which the pulse is applied to the transmitting crystal is the ________
indication.
a) initial pulse
b) threshold
c) R-F
d) sweep
a) initial pulse
To avoid distortion of received ultrasonic signals the receiver amplifier should have similar bandwidth characteristics as the
a) test piece resonant frequency
b) receiving transducer
c) transmitting transducer
d) none of the above, receiver bandwidth is not important
b) receiving transducer
The IIW block is used primarily
a) for contact probes
b) for angle beam probes
c) for immersion work
d) in place of the IOW block
a) for contact probes
In plate testing with angle beams, the full skip distance refers to
a) the sound path to the opposite wall
b) twice the sound path to the opposite wall
c) the plate thickness
d) twice the plate thickness
b) twice the sound path to the opposite wall
Variations in acoustic pressure at right angles to the probes’ sound beam in the near zone are a result of
a) side lobes
b) overtones
c) sub harmonics
d) divergence
a) side lobes
Severity of a defect is determined by
a) amplitude of signal relative to reference
b) length of flaw
c) type and orientation of flaw
d) all of the above
d) all of the above
Which of the following methods would not use pulsed ultrasound?
a) pulse-echo
b) pitch-catch
c) through-transmissions
d) all of the above would use pulse ultrasound
d) all of the above would use pulse ultrasound
The advantage of magnetrostrictive transducers is
a) sturdiness
b) resistance to damage under adverse conditions
c) ability to be constructed in very large sizes
d) all of the above
d) all of the above
Flaw detection using the through transmission method can give accurate information about
a) flaw depth
b) flaw type
c) flaw orientation
d) none of the above
d) none of the above
When drawing a distance/amplitude curve (DAC) you set the signal from the reference hole which gives the maximum
amplitude to
a) 100% full screen height (FSH)
b) 80% - 90% FSH
c) 50% FSH
d) 12 dB over the response from the 7/8 node
b) 80% - 90% FSH
Wavelength of sound is determined by
a) (velocity) / (frequency)
b) (frequency) / (velocity)
c) (frequency) X (velocity)
d) none of the above
a) (velocity) / (frequency)
The plastic prism coupled between and ultrasonic transducer and a test piece which causes the ultrasonic waves to propagate
at a known angle within the test piece is called a
a) wedge
b) solid couplant
c) variable angle adapter
d) none of the above
a) wedge
Manual probe movement in contact scanning to evaluate a defect for type is
a) in the lateral direction
b) in a transversing direction
c) both orbital and rotational
d) always a combination of all of the above
d) always a combination of all of the above
Mechanical deformation of a material placed in a magnetic field is called
a) magnetostriction
b) warp factor
c) reverse piezoelectric effect
d) undulation
a) magnetostriction
To improve the accuracy of defect location and evaluation you should
a) reduce gain
b) increase range
c) check calibration
d) use a probe of higher frequency
c) check calibration
Most codes would recommend the actual beam angle of an angle beam probe not deviate from the indicated angle by more than
a) one half degree
b) one degree
c) two degrees
d) five degrees
c) two degrees
Waves used in ultrasonic testing of materials are ___________ in nature.
a) mechanical
b) magnetic
c) electromagnetic
d) harmonious
a) mechanical
The result of a rough test surface in ultrasonic testing is
a) reduced acoustic coupling
b) beam distortion
c) to change the wavelength of sound in the test piece
d) both a and b
d) both a and b
A rough surface may affect resolution and sensitivity by
a) increasing scatter
b) causing unwanted mode conversions
c) decreasing coupling
d) all of the above
d) all of the above
Acoustic pressure along the beam axis moving away from the probe has various maxma and minima due to interference. At
the end of the near field pressure is
a) a maximum
b) a minimum
c) the average of all maxima and minima
d) none of the above
a) a maximum
Which mode of wave used in nondestructive testing is not initially produced by mode conversion?
a) longitudinal
b) shear
c) transverse
d) Rayleligh
a) longitudinal
Surface waves limited on two surfaces are also called
a) long. waves
b) lamb waves
c) shear waves
d) P waves
b) lamb waves
Which is not a commonly used target when establishing sensitivity for ultrasonic testing?
a) side drilled holes
b) a tungsten ball
c) the 100 mm quadrant of the IIW block
d) flat bottom holes
b) a tungsten ball
A focused probe is positioned in water 5 cm over a plate 10cm thick. The probe having a focal length of 6 cm will focus
a) 1 cm above the plate
b) 0.25 cm from the entry surface of the plate
c) 0.25 cm from the back surface of the plate
d) 0.4 cm into the water on the opposite side of the plate
b) 0.25 cm from the entry surface of the plate
Most piezoelectric ceramics (ferroelectrics) are
a) polycrystalline
b) also ferromagnetic
c) statically charged
d) are better receivers than transmitters
b) also ferromagnetic
The method whereby sound is transmitted through a plate from a transmitter on one side to a receiver on the other
a) is used to characterize flaws
b) is called an intensity method
c) is used to determine flaw depth
d) all of the above
b) is called an intensity method
Significant advantage of ultrasonics over radiography is
a) it is safe
b) it can be used on ferrous and non-ferrous metals
c) all defects in any piece can be located
d) the ability to use it underwater
a) it is safe
Scatter is more likely to be a problem if
a) grain size is small
b) grain size is large
c) a material is isotropic
d) grain crystals are cubic
b) grain size is large
When contact testing is performed, a transfer value is
a) used to compensate for attenuation
b) used to compensate for variations in coupling
c) both a and b
d) not used
c) both a and b
Methods of generating and receiving ultrasound by deformation of ferromagnetic materials in a magnetic field utilize the phenomenon called
a) magnetics
b) electrodynamics
c) magnetostriction
d) eddy currents
c) magnetostriction
In addition to a low critical temperature, lithium sulphate hydrate
a) is soluble in water so must be water proofed
b) is a poor impedance match to water
c) has the lowest coupling coefficient
d) none of the above
a) is soluble in water so must be water proofed
When using quartz as a piezoelectric transducer, longitudinal waves are generated from the
a) X - cut
b) Y - cut
c) Z - cut
d) GT - cut
a) X - cut
Flat bottom hole test blocks are made
a) of the same alloy as the test piece
b) with varying depth from the test surface to compare response at different distances from the probe
c) with different target sizes to establish reflection equality between a flaw and a standard
d) all of the above
d) all of the above
Pulse length determines a probes’
a) frequency
b) acoustic impedance
c) damping
d) depth resolution
d) depth resolution
The dominant frequency of an ultrasonic flaw detection system depends on the
a) probe
b) machine receiver and amplifier
c) pulse propagation path
d) all of the above
d) all of the above
The effect of increasing the temperature of a test piece to 30 degrees C. is to
a) improve acoustic coupling
b) decrease resolution
c) require high temperature couplant
d) decrease acoustic velocity
d) decrease acoustic velocity
If a signal is reduced from 84% to 42% FSH, the number of dB gain removed from the receiver is
a) 2
b) 6
c) 12
d) 42
b) 6
Although quartz has about twice the receiving sensitivity of PZT, PZT used for pulse-echo testing in NDT results in higher
amplitude signals for the same conditions because
a) transmission constant is higher
b) PZT dielectric constant is lower
c) PZT has a lower density
d) all of the above
a) transmission constant is higher
Spreading the timebase interval to enable signals from a selected range to be displayed is called
a) magnification
b) delay
c) scale expansion
d) decompression
c) scale expansion
A large Q factor indicates
a) high damping
b) narrow bandwidth
c) wide bandwidth
d) low permeability
b) narrow bandwidth
More scatter of a sound beam is had when using
a) high PRF
b) short pulse lengths
c) higher frequency probes
d) lucite delay lines
c) higher frequency probes
Resonance testing methods are used for
a) determining Poisson’s ratio
b) flaw detection
c) thickness testing
d) all of the above
c) thickness testing
When performing contact angle beam testing interferring surface waves can be distinguished from flaws by
a) triangulation
b) testing from the opposite side
c) touching the work surface with an oily finger
d) none of the above
c) touching the work surface with an oily finger
A property of the receiver amplifier that is periodically verified is
a) horizontal linearity
b) vertical linearity
c) beam spread
d) near zone
b) vertical linearity
Unless otherwise noted, the refracted beam angle on a perspex wedge is the refracted angle in
a) aluminum
b) brass
c) plastic
d) steel
d) steel
Thickness measurements of plates are made using ______ waves.
a) Rayleigh
b) shear
c) compressional
d) Lamb
c) compressional
A calibration block can be used to
a) check instrument and probe characteristics
b) set sensitivity for inspection
c) reproduce previously used settings
d) all of the above
d) all of the above
The position of a defect found by an angle beam inspection requires that you know
a) the refracted angle and exit point
b) sound path distance
c) geometry and dimensions of the test piece
d) all of the above must be known
d) all of the above must be known
The number of oscillations per second experienced by a particle as an acoustic wave passes through it is called the
a) wavelength of the oscillation
b) acoustic frequency
c) period of oscillation
d) none of the above
b) acoustic frequency
AVG (or DGS in English) diagrams are used for
a) establishing gain settings
b) determining vertical beam spreads
c) estimating flaw size
d) none of the above
c) estimating flaw size
Lithium sulphate as a transducer material is most notable for its
a) high curie point
b) low coupling coefficient
c) high solubility in water
d) none of the above, lithium sulphate is not used as a transducer material
c) high solubility in water
In ultrasonic spectrum analysis, the effect of increasing metal grain size on the spectra would be
a) reduction in lower frequencies
b) reduction in higher frequencies
c) an increase in frequencies at the corresponding grain size
d) none of the above
b) reduction in higher frequencies
Generally, longitudinal waves propagate__________.
a) faster than shear waves
b) slower than shear waves
c) at right angles to shear waves
d) parallel to shear waves
a) faster than shear waves
For an ultrasound beam to skip in the circumferential direction of a tubular product
a) the ratio of inside to outside diameter must be right
b) the incident angle must be sufficiently steep
c) both a and b
d) none of the above
c) both a and b
The most common single measurement made on ultrasonic transducers is determination of
a) nature of sound field
b) bandwidth
c) actual centre frequency
d) none of the above
a) nature of sound field
Surface wave ultrasonic testing is superior to penetrant testing because it
a) is cheaper
b) is faster
c) can find sub-surface defects
d) can be used on ferro-magnetic materials
c) can find sub-surface defects
The purpose of highly absorptive backing material in transducers used for testing is to
a) eliminate sound re-entering the crystal
b) maximize rise time
c) maximize fall time
d) obtain highest resolution by broadening the frequency bandwidth
a) eliminate sound re-entering the crystal
When performing a pulse-echo test, if you scanned over a large defect with the same acoustic impedance as the material you were testing
a) maximum response would occur only at right angles
b) the AVG (DGS) method would be used for sizing
c) it would not be detected
d) detection would depend on how much gain over reference you were scanning with
c) it would not be detected
Short highly damped pulses of ultrasound have their advantage in NDT in that
a) sensitivity is increased
b) time measurement accuracy is improved
c) defect characterizations is simplified
d) all of the above
b) time measurement accuracy is improved
A deviation in actual refracted angle of + or - 2 degrees will result in
a) errors in depth calculations
b) errors in stand-off calculations
c) errors in sound path calculations
d) both a and b
d) both a and b
The principles involved in testing non-metals by ultrasonics as compared to metals are
a) significantly different with regards to coupling only
b) simpler because shear waves are not involved
c) more complex due to birefringence
d) essentially the same
d) essentially the same
The best way to determine the required sensitivity for ultrasonic testing is
a) to use 20 dB over the gain needed to put the 1.5 mm diameter hole of the IIW block to 80% FSH
b) use enough gain to get “10% grass” from the opposite wall
c) use reference welds with real defects of the minimum acceptable size
d) from flat bottom hole and side drilled hole response studies
c) use reference welds with real defects of the minimum acceptable size
The critical angle for the transverse wave is also called the
a) right angle
b) Snell angle
c) first critical angle
d) second critical angle
d) second critical angle
If a 1 MHz quartz crystal (cut for half-wave resonance) is 0.29 cm thick, how thick would it have to be if the half-wave resonance frequency was to be 10 MHz?
a) 0.29 mm
b) 2.9 mm
c) 2.9 cm
d) 5.8 microns
a) 0.29 mm
In ultrasonic testing a piezoelectric material is used to
a) convert electric energy to mechanical energy
b) convert mechanical energy to electrical energy
c) both a and b
d) none of the above
c) both a and b
When performing contact ultrasonic testing, significant amplitude variations from the same indication can result from
a) transducer angle
b) couplant thickness
c) probe wear face thickness
d) all of the above
d) all of the above
Particle motion in a longitudinal wave is
a) parallel to the direction of wave propagation
b) at right angles to the direction of wave propagation
c) retrograde
d) in counterclockwise ellipses
a) parallel to the direction of wave propagation
In some ultrasonic probe arrangements, one variety of piezo material is used for the transmitter and another for the receiver. The purpose of two different materials is
a) to make fabrication of the probe easier
b) to take advantage of broadband receivers
c) to optimise relative efficiencies of transmitter and receiver elements
d) all of the above
c) to optimise relative efficiencies of transmitter and receiver elements
The phenomenon whereby a longitudinal wave generates waves of other modes upon reflection or refraction is
a) total internal reflection
b) mode conversion
c) conversion mechanics
d) none of the above
b) mode conversion
The amount by which the electrical signal from the ultrasonic transducer is amplified is
a) the gain
b) signal-to-noise ratio
c) 6
d) none of the above
a) the gain
The purpose of water jets in ultrasonic inspection of hot plate (100°C.) is
a) to provide a coupling medium
b) to keep the probe cool
c) both a and b
d) none of the above
c) both a and b
When a longitudinal wave is directed along the length of a large solid shaft from an end of the shaft, sensitivity to defects fluctuates as the probe is moved from the centre to the outside edge of the shaft. This is accounted for by
a) interfering edge effects
b) the near zone
c) mode conversion
d) none of the above
a) interfering edge effects
Higher frequency probes are not preferred for inspection of castings due to
a) poor directivity
b) higher coefficients of transmission
c) higher coefficients of reflection
d) scatter
d) scatter
If not equipped with a frequency selector for the receiver amplifier an ultrasonic machine would probably use a (an)
a) broadband receiver
b) wide receiver
c) ineligible receiver
d) tight end
a) broadband receiver
Shifts of the positive charge on the silicon and negative charge on the oxygen in a quartz crystals account for
a) twin crystals
b) the piezoelectric effect
c) polymorphs
d) none of the above
b) the piezoelectric effect
The method of non-destructive testing which uses acoustic energy usually in the 1MHz to 5 MHz range is
a) sub-sonic testing
b) ultrasonic testing
c) E-M testing
d) acoustic flux leakage testing
b) ultrasonic testing
The purpose of moving a contact angle beam probe back and forth perpendicular to the axis of the weld inspected is to
a) evaluate defects
b) eliminate the need for scanning from 2 sides
c) ensure full volumetric inspection of weld and heat affected zone
d) practice echo-dynamics
c) ensure full volumetric inspection of weld and heat affected zone
When ferro electric ceramics such as PZT are heated to above their curie point and held under a bias voltage while cooling to 80øC they are considered
a) neutralized
b) annealed
c) poled or polarized
d) charged
c) poled or polarized
For a plane wave, sound pressure is reduced by attenuation in a _______ fashion.
a) linear
b) exponential
c) random
d) none of the above
b) exponential
If a material borders on empty space the interface is called
a) a vacuum
b) infinity
c) a free boundary
d) none of the above
c) a free boundary
The testing of materials to detect internal, surface and concealed defects or discontinuities by methods which do not damage or destroy the material under test is called
a) surveillance testing
b) electromagnetic testing
c) acoustic testing
d) non-destructive testing
d) non-destructive testing
The purpose of determining signal-to-noise ratio is
a) to verify good coupling
b) necessary to ensure small flaws do not go undetected
c) a check on the accuracy of the attenuator
d) a check on the sensitivity afforded by uncalibrated gain
b) necessary to ensure small flaws do not go undetected
When using perspex wedges for contact testing, if the actual refracted angle varies by more than + or - 2 degrees the wedge
should be
a) replaced
b) re-ground
c) re-calibrated
d) a or b
d) a or b
Modern ultrasonics uses signal processing methods like signal averaging, spectral analysis, deconvolution auto-correlation
and filtering to
a) increase scanning speeds of automated systems
b) eliminate ultrasonic operators
c) provide smoother looking A-scans
d) both locate and characterize flaws
d) both locate and characterize flaws
Transducers with high-Q factor have
a) broadband-type pulses
b) poor penetrating ability
c) poor resolution compared to low-Q factor
d) all of the above
c) poor resolution compared to low-Q factor
The delta technique uses
a) a single pulse echo probe
b) a transmitting probe and receiving probe on the same side of the test piece
c) a transmitting probe and receiving probe on opposite sides of the test piece
d) there is no such technique
b) a transmitting probe and receiving probe on the same side of the test piece
The preferred presentation method for determining the amplitude of a echo signal is the
a) A-scan
b) B-scan
c) C-scan
d) D-scan
a) A-scan
Ultrasonics used for drilling or machining has the advantage that
a) no cutting fluids are required
b) complex shapes can be cut out in a single pass
c) the workpiece does not heat up locally
d) all of the above
b) complex shapes can be cut out in a single pass
The incident angle at which the longitudinal mode is refracted at 90° is
a) 27 degrees
b) the first critical angle
c) the second critical angle
d) not used in NDT
b) the first critical angle
The fundamental frequency of a piezoelectric crystal used in ultrasonics is a function of
a) its thickness
b) the velocity of sound in the crystal material
c) both a and b
d) none of the above
c) both a and b
Pulse-echo ultrasonic testing is used for
a) thickness testing
b) flaw detection
c) acoustic velocity determinations
d) all of the above
d) all of the above
Ultrasonic testing of concrete would be carried out using frequencies in the range of
a) 100 to 500 Hz
b) 25 to 100 kHz
c) 0.5 to 1 MHz
d) 2 to 4 MHz
b) 25 to 100 kHz
Velocity of ultrasonic waves in steel at 10°C. as compared to 40°C. are
a) slower
b) faster
c) the same
d) dependant on the alloy of steel maybe faster or slower
b) faster
The parallel of mechanical resonance frequency of a piezoelectric element occurs when the element thickness is
a) one quarter wavelength
b) one half wavelength
c) one wavelength
d) none of the above
b) one half wavelength
Rayleigh waves are a phenomenon associated with
a) solid to liquid boundaries
b) solid to air boundaries
c) solid to solid boundaries
d) all of the above
d) all of the above
In ultrasonic testing by pulse-echo method, the sound waves off the probe are
a) omni-directional
b) a single frequency
c) a range of frequencies
d) non-existent in the dead zone
c) a range of frequencies
Rayleigh, shear and longitudinal describe
a) wave forms
b) wave modes
c) wave lengths
d) wave guides
b) wave modes
Another term for the suppression control on an ultrasonic machine is
a) reject
b) damping
c) attenuation
d) gain
a) reject
Surface wave testing would be used to detect
a) lamination in 10mm thick plate
b) microshrinkage in magnesium castings
c) slag inclusions in submerged arc welds
d) fatigue cracks in helicopter blades
d) fatigue cracks in helicopter blades
The “bending” of sound waves at gaps and openings is accounted for by
a) reflection
b) diffraction
c) density
d) acoustic pressure
b) diffraction
A plane longitudinal wave strikes a water-steel interface from water ( V long water=1.5Km/s V long steel= 5.9km/s V shear
steel=3.2km/s ) at normal incidence. Having had a 2mm wavelength in water it will result in the shear wave wavelength being
a) 2.6mm
b) 1.5mm
c) 0.8 mm
d) none of the above, a shear wave does not occur
d) none of the above, a shear wave does not occur
A contact probe which introduces an ultrasonic wave into a test piece so that the beam angle in the test piece is a some angle
other than 0 or 90 degrees to the normal is called a(n)
a) angle probe or angle beam probe
b) shear wave probe
c) dry coupling probe
d) Rayleigh probe
a) angle probe or angle beam probe
The product of acoustic velocity times the density of a material gives
a) power intensity
b) frequency
c) wavelength
d) acoustic impedance
d) acoustic impedance
The gain required to compensate for differences in coupling efficiency between a reference or calibration block and the work
piece is called
a) transfer correction or transfer value
b) absorption coefficient
c) scatter modulus
d) attenuation constant
a) transfer correction or transfer value
According to geometric-optic treatment of sound, acoustic pressure
a) increases with distance from source
b) decreases with distance from source
c) varies unpredictably with distance from source
d) none of the above
b) decreases with distance from source
The short wave-train produced on each excitation of an ultrasonic transducer is a(n)
a) acoustic tone burst
b) half-wave
c) pulse
d) surface acoustic wave
c) pulse
Which of the following is not a magnetostrictive material
a) cobalt
b) PZT
c) nickel
d) iron
b) PZT
When using the large IIW Block #1, what are the fewest number of reflections from the 100mm radius in order to calibrate a 70
degree shear wave probe for a 100mm range?
a) 1
b) 2
c) 2 1/2
d) 3
b) 2
In a ferroelectric ceramic such as PZT, the curie temperature is the temperature above which
a) the piezoelectric domain structure is lost
b) water is driven out of the crystal
c) polarity reverses
d) electrodes cannot be deposited
a) the piezoelectric domain structure is lost
Given a 2 MHz PZT crystal coupled to steel at an angle of incidence of 3°, what is the wavelength of the shearwave in steel if
V long is 5.9mm/µs and V shear is 3.2mm/µs?
a) 0.63 mm
b) 1.6 mm
c) 6.4 mm
d) a shear wave will not be present
b) 1.6 mm
The most commonly used wave mode for angle beam testing is
a) longitudinal
b) transverse
c) Rayleigh
d) Lamb
b) transverse
For a longitudinal wave entering a medium of lower acoustic velocity, the refracted longitudinal wave angle in the new material will be
a) totally internally reflected
b) the same
c) less than incidence angle
d) greater than incidence angle
c) less than incidence angle
“Delay” on the ultrasonic machine is used to
a) reduce grass level
b) compensate for range errors
c) correct for proper zero point
d) adjust lag on the pulser
c) correct for proper zero point
Tubing ie. tubular products, is best inspected by ultrasonics using the __________ method.
a) pulse-echo
b) transmit-receive
c) induction coil
d) time of flight diffraction
a) pulse-echo
For immersion testing, surface scale and rust can be removed by
a) steel brushes and scrapping
b) sand blasting and grinding
c) both a and b
d) none of the above, cleaning is not needed for immersion testing
c) both a and b
The incident angle at which the transmitted transverse wave first ceases to exist in the refracting medium is called the
a) long angle
b) short angle
c) first critical angle
d) second critical angle
d) second critical angle
The ratio of vibration amplitude at resonance frequency to the amplitude of static thickness change is called
a) fo
b) fr
c) the modulus of resonance
d) Q factor
d) Q factor
In transverse waves, particle motion is
a) parallel to the direction of wave propagation
b) right angles to the direction of wave propagation
c) retrograde
d) in counterclockwise ellipses
b) right angles to the direction of wave propagation
Attenuation of ultrasonic energy is an inherent property of all materials and is
a) a constant 0.5 dB/cm
b) variable with alloy and test frequency
c) a function of acoustic impedance
d) both b and c
b) variable with alloy and test frequency
The purpose of putting one or more matching layers between the front face of a probe and the coupling medium is
a) to decrease ringing time
b) to improve coupling
c) to provide a delay line effect
d) not known by probe manufacturers
b) to improve coupling
For a single crystal piezoelectric material used in an ultrasonic transducer the angle to the crystal axis that it is cut determines
a) frequency
b) direction of deformation
c) Q-factor
d) both a and b
b) direction of deformation
The orientation of the defect with respect to the direction of the ultrasonic beam determines
a) whether the reflected pulse returns to the receiver
b) if immersion or contact testing is used
c) if immersion or gap testing is used
d) none of the above
a) whether the reflected pulse returns to the receiver
If a signal on your CRT is 28% FSH and 6 dB gain is added to the receiver amplifier the signal will be _______ FSH.
a) 34%
b) 42%
c) 56%
d) 70%
c) 56%
Acoustic imaging techniques permit the visualization of objects because
a) sound can be converted to light when passing through metal
b) of the polarity of transverse waves
c) sonoluminescence occurs in couplant
d) acoustic waves obey the same equations as optical waves
d) acoustic waves obey the same equations as optical waves
Using the through transmission method of ultrasonic testing
a) no couplant is needed
b) no flaw echo is seen
c) only one transducer is used
d) fillet welds are best tested
b) no flaw echo is seen
Uniformity of coupling is verified by the operator monitoring
a) backwall amplitude
b) “grass” level
c) a and b
d) calibration
c) a and b
Although ingots of metal are often difficult to test by ultrasonics due to large dimensions and scatter due to grain size, it is
useful to locate
a) laminations
b) bursts
c) gross piping
d) cold shots
c) gross piping
A material that exhibits dimensional changes in a magnetic field is said to be
a) electrostrictive
b) ferroelectric
c) magnetostrictive
d) electromagnetic
c) magnetostrictive
The method whereby the test piece is either wholly or partially under water or other such coupling fluid is called
a) gap testing
b) jet testing
c) plate testing
d) immersion testing
d) immersion testing
The law of reflection requires that
a) the angle of reflection equals the angle of incidence
b) the normal to the reflecting surface, the reflected ray and incident ray lie in the same plane
c) both a and b
d) none of the above
c) both a and b
Probe index, refracted angle, timebase and sensitivity are usually calibrated using
a) calibrator electronics
b) tuning forks
c) calibration and or reference blocks
d) the test piece itself
c) calibration and or reference blocks
A typical maximum thickness range for inspecting forged steel by ultrasonics is
a) 0.5 to 1m
b) 1 to 2 m
c) 1 to 10 m
d) 10 to 100 m
c) 1 to 10 m
Maximum acoustic energy is coupled from one medium to another when the acoustic impedance of the first medium is
_________ the second.
a) less than
b) greater than
c) the same as
d) twice the value of
c) the same as
When inspecting a thin flat plate with a 60ø shear wave probe it is possible to see both top and bottom corners of the plate
when the beam is aimed at the plate edge. This is due to
a) ghosting
b) splitting
c) beam spread
d) none of the above
c) beam spread
If the sound beam strikes a flaw at right angles and the flaw has a greater area than the beam it will
a) cause resonance
b) absorb most of the beam energy
c) cause destructive interference
d) at like a backwall
d) at like a backwall
Material attached to the rear of an ultrasonic crystal to increase damping is called
a) tuning material
b) matching
c) crystal backing
d) none of the above
c) crystal backing
Background indications seen on an A-scan, arising from material characteristics and/or electrical noise is termed
a) grass
b) interference
c) pick-up
d) hash
a) grass
Thickness readings from ultrasonic testing can be indicated by
a) reading the position of pips on a CRT screen
b) meter or digital readout
c) graphing by a pen on strip chart paper
d) all of the above
d) all of the above
A PZT transducer will loose its piezoelectric property if
a) immersed in water
b) used on a forging that has not been de-magnetized
c) used on a surface whose temperature is 140 degrees C
d) heated above its curie point
d) heated above its curie point
If the “focal spot” size of the beam from a focused transducer was increased by increasing the focal length
a) sensitivity would increase
b) resolution would decrease
c) all flaws would be detected
d) no indications would be rejectable
b) resolution would decrease
Sound reduction over a distance can be accounted for by
a) absorption
b) scatter
c) beam spreading
d) all of the above
d) all of the above
The advantage of a short duration excitation pulse applied to a normal transducer is
a) wideband frequency operation
b) high resolution
c) reduced attenuation loses
d) all of the above
d) all of the above
In ultrasonic testing, the display in which pulse amplitude is represented as a displacement along one axis and time as a
displacement along the other axis is called a(n)
a) A-scan
b) B-scan
c) C-scan
d) isometric display
a) A-scan
The number of nanoseconds in 2 milliseconds is
a) 0.002
b) 2000
c) 2 X 10^6
d) 2 X 10^9
c) 2 X 10^6
Of the various materials used for transducer crystals, lithium sulphate hydrate is the most critical because it
a) looses its water of crystallization above 130 degrees C
b) breaks down at excitation voltages over 500 V
c) cannot be used in immersion testing
d) all of the above
a) looses its water of crystallization above 130 degrees C
The piezoelectric material first used for ultrasonic transducers is
a) PZT
b) SiO2 (quartz)
c) Na Cl
d) PVDF
b) SiO2 (quartz)
The main contribution to loss of sound pressure of a beam incident on a rough surface is provided by
a) scatter
b) mode conversion
c) refraction
d) diffraction
a) scatter
In determining the coefficient of reflection, a negative value indicates
a) reduced amplitude
b) loss of sound pressure
c) phase reversal relative to the incident wave
d) none of the above
c) phase reversal relative to the incident wave
Rubber tires can be inspected by ultrasonic means but it requires lower frequencies in the range of 50 kHz because
a) high frequencies delaminate the rubber
b) high frequencies uncure the rubber
c) of attenuation from scatter off the fibres
d) none of the above
c) of attenuation from scatter off the fibres
Given a cube of iron (long. velocity = 5800 m/s), pulse-echo multiples are seen every 100 microseconds. What is the thickness of the iron?
a) 100 mm
b) 29 mm
c) 29 cm
d) 58 cm
c) 29 cm
For normal ultrasonic contact testing of forged carbon steel and aluminum the optimum frequency range of transducers is
a) 100 to 500 kHz
b) 0.5 to 1 MHz
c) 2 to 5 MHz
d) 10 to 15 MHz
c) 2 to 5 MHz
Using the pulse echo method with a 0 degrees probe (single crystal) on a flat steel plate 50mm thick, the pattern on the CRT
would appear as
a) evenly spaced multiples
b) randomly spaced multiples
c) multiples with increasing spacing between them
d) none of the above
a) evenly spaced multiples
The line of maximum sound intensity in the far zone of an ultrasonic beam, and its projection back to the near zone is called
the
a) half angle of divergence
b) beam spread
c) beam profile
d) beam axis
d) beam axis
Bending of a sound wave upon entering a new medium is explained by
a) Krautkramer’s law
b) Snell’s law
c) Boyle’s law
d) Hooke’s law
b) Snell’s law
The difference between a thickness gauge and a distance gauge is
a) the range that is measured
b) velocities involved
c) type of piezoelements used
d) all of the above
a) the range that is measured
You are given a cube of material 20mm thick. By pulse-echo immersion testing you determine the multiples of this material to be separated by 6.9 microseconds, the longitudinal velocity of sound in the material is
a) 1500 m/s
b) 3450 m/s
c) 5800 m/s
d) 6900 m/s
c) 5800 m/s
In contact testing using angle beam probes with removable wedges, the purpose of groves in the front of the wedge is
a) to prevent couplant buildup
b) increase resolution
c) absorb internally reflected sound
d) all of the above
c) absorb internally reflected sound
Which of the following is not a consideration when choosing a couplant for ultrasonic testing
a) type of material tested
b) surface finish of test piece
c) orientation of test surface
d) nominal test frequency
d) nominal test frequency
High frequency transducers, over 10 MHz, have
a) little use in contact testing
b) very thin crystals
c) good sensitivity to minute defects
d) all of the above
d) all of the above
When calibrating for an inspection range of 0 to 100mm with an angle beam probe, delay on the instrument must be
a) increased
b) decreased
c) left untouched
d) adjusted to correct for the time delay in the perspex wedge
d) adjusted to correct for the time delay in the perspex wedge
In order to generate mechanical displacements (ultrasound waves) in a X-cut piezoelectric crystal we must
a) squeeze the crystal
b) heat the crystal
c) apply an alternating voltage
d) none of the above
c) apply an alternating voltage
In contact testing best probe contact is made on ________ surfaces.
a) flat
b) convex
c) concave
d) 250 RMS surfaces
a) flat
Production line testing of high pressure ribbed tubing would use which ultrasonic technique?
a) contact testing
b) immersion testing from the outside diameter
c) immersion testing from the inside diameter
d) the bubbler technique
c) immersion testing from the inside diameter
Which is not a welding defect term
a) porosity
b) slag
c) lamination
d) hot cracking
c) lamination
Standing waves in any medium are result of
a) interference from reflections
b) the PRF
c) wave splitting
d) mode conversion at boundaries
a) interference from reflections
The “main lobe” of a rectangular probe is
a) axially symmetric
b) broader in the small probe dimension
c) narrower in the small probe dimension
d) two dimensional
b) broader in the small probe dimension
A negative value of a reflection coefficient indicates
a) no phase change has occurred
b) 90° phase change
c) 180° phase change
d) a decrease in amplitude
c) 180° phase change
Sizing of defects located in the near zone is difficult because of
a) uncertainties of sound pressure along the beam axis
b) uncertainties of sound pressure at right angles to the beam axis
c) frequency variation
d) both a and b
d) both a and b
Mechanical methods of ultrasound generation
a) utilise electro-mechanical hammers
b) utilise rotating wire brushes
c) require no coupling liquids
d) all of the above
d) all of the above
When performing contact weld inspection the purpose of doing a normal beam inspection of the parent metal adjacent to the weld is
a) to establish material thickness
b) to locate laminations or other impeding inclusions
c) to note variations in attenuation
d) all of the above
d) all of the above
Which of the following plate defects would not be a result of inservice use?
a) stress-corrosion cracking
b) laminations
c) fatigue cracking
d) pitting
b) laminations
2,500,000 cycles per second (cps) is also expressed as
a) 25 kHz
b) 2.5 MHz
c) 2.5 mHz
d) 25 GHz
b) 2.5 MHz
The recommended refracted angle for contact shear wave inspection of plate less than 10mm thick is
a) 45°
b) 60°
c) 70°
d) all of the above
c) 70°
Beyond the near zone of an ultrasound beam from a probe is the
a) dead zone
b) Fresnel zone
c) far field
d) null zone
c) far field
So as to be utilized as ultrasonic transducers, ferroelectric ceramics must
a) be heated above their curie point
b) poled
c) be put into an electric field
d) all of the above
d) all of the above
The point where no particle displacement occurs on a standing wave is called
a) an anticline
b) an antinode
c) a node
d) a dead zone
c) a node
The most common method of ultrasonic testing of welds is
a) continuous wave resonance
b) normal beam
c) angle beam
d) through-transmission
c) angle beam
In weld inspection, transverse cracks are best located by
a) scanning at right angles to the weld axis
b) scanning parallel to the weld axis
c) the lamination scan
d) immersion testing
b) scanning parallel to the weld axis
The display generated so that distance along a horizontal axis is proportional to time is a(n)
a) time base
b) C-scan
c) unrectified display
d) none of the above
a) time base
An acoustic lens for focusing ultrasound at a specific point in front of the transducer is made as thin as possible so as to
a) make the probe as light as possible
b) obtain the shortest focal length
c) minimize absorption
d) all of the above
c) minimize absorption
An echo received from a reflector of known size and characteristics could be termed a
a) reference echo
b) spurious echo
c) ghost echo
d) solid echo
a) reference echo
Transmitter voltage pulse is triggered by the
a) probe resonance
b) control pulse of the sweep generator
c) sweep delay control
b) control pulse of the sweep generator
Given a 4 MHz probe radiating normally into copper, V long = 4.7 km/s V shear = 2.3km/s, the wavelength of the longitudinal wave is
a) 0.85mm
b) 1.18 mm
c) 2.36mm
d) 2.99mm
b) 1.18 mm
Acoustic pressure fluctuates in the near zone due to
a) diffraction interference
b) dispersion
c) refraction
d) density fluctuations
a) diffraction interference
Applied voltage on a piezoelectric crystal used in a transducer requires ________ to cause mechanical displacement
a) electrodes
b) vibration
c) heat
d) all of the above
a) electrodes
A presentation where-by the relative amplitude of ideal reflectors of different sizes are plotted against different distances is called
a) DGS diagrams
b) AVG diagrams
c) DAC curves
d) both a and b
d) both a and b
The interference pattern produced in front of a transducer face is a result of
a) rarefaction
b) dispersion
c) diffraction
d) refraction
c) diffraction
Scatter generally increases with
a) increasing grain size
b) decreasing wavelength
c) increasing frequency
d) all of the above
d) all of the above
Maximum amplitude response of a planar defect will usually be had when
a) its main surface is perpendicular to the sound beam
b) its main surface is parallel to the sound beam
c) its main surface is oblique to the sound beam
d) none of the above, amplitude will be about equal for a given flaw regardless of orientation
a) its main surface is perpendicular to the sound beam
Amplitude response of a defect is not influenced by
a) equipment settings and probe characteristics
b) attenuation
c) defect location and orientation
d) none of the above
d) none of the above
When using the “pitch-catch” method of ultrasonic testing, which is not true?
a) two piezoelectric elements are commonly used
b) all the piezoelements are mounted in one housing
c) both shear and longitudinal modes can be used
d) one element is dedicated to transmission
b) all the piezoelements are mounted in one housing
If you wanted to determine the depth a large surface breaking crack extending into a plate you were inspecting using an angle beam, you would need to know
a) soundpath distance
b) actual refracted angle
c) total forward/backward travel of the probe
d) all of the above
d) all of the above
As temperature of a solid increases the attenuation of sound in that object tend to
a) increase
b) decrease
c) remain constant
d) vary sinusoidally
a) increase
In ultrasonic testing the term sensitivity usually refers to the test system’s ability to discern
a) small distances between defects
b) the angular separation between defects
c) the smallest size defect
d) none of the above
c) the smallest size defect
Ultrasonic waves with frequencies of 400MHz to 2GHz would be used in
a) acoustic microscopy
b) concrete testing
c) ultrasonic cleaning
d) nothing, it is not possible to generate ultrasound in this range
a) acoustic microscopy
Given a 10 MHz probe vibrating into water, with a velocity of 1.5 mm/µs, what is the wavelength of the longitudinal wave
a) 0.15 mm
b) 1.5 mm
c) 1.5 cm
d) 0.6 cm
a) 0.15 mm
The length of a defect is calculated from
a) DGS diagrams
b) lateral probe movement
c) amplitude
d) horizontal displacement of the signal on the timebase
b) lateral probe movement
Alignment of the small domains in polycrystalline ferro-electric materials, such as PZT, is called
a) poling
b) polarisation
c) both a and b
d) domaining
c) both a and b
In immersion testing, the hindrance of multiple interface signals that results from the pulse bouncing between the test piece and probe on normal incidence is avoided by
a) decreasing receiver gain
b) increasing the distance between probe and work surface
c) increasing damping
d) use of the interface-lock feature
b) increasing the distance between probe and work surface
Reference reflectors in calibration blocks are normally cylindrical holes because
a) they are easier to machine
b) they best represent actual defects
c) they are not as directionally dependant
d) none of the above
c) they are not as directionally dependant
The angle at which an ultrasonic beam spreads in the far zone is called the
a) wave angle
b) phase angle
c) angle of repose
d) angle of divergence
d) angle of divergence
A system that electronically monitors an echo signal in a gate such that an alarm is triggered if the signal exceeds a predetermined amplitude is called a / an
a) B-scan
b) go / no-go system
c) early warning system
d) sweep generator
b) go / no-go system
The purpose applying ultrasound to a weld puddle during electric arc welding is to
a) prevent lack of penetration
b) increase heat in the weld puddle
c) create a finer grain structure and increase tensile strength
d) eliminate the requirement for radiographic testing
c) create a finer grain structure and increase tensile strength
When trying to obtain a “noise free” signal a filter is sometimes used. If this filter limits signals to just a narrow range of frequencies it is called a _________ filter.
a) low-pass
b) high-pass
c) band-pass
d) broadpass
c) band-pass
Attenuation of ultrasound by absorption is a result of
a) reflection
b) refraction
c) scatter
d) heating
d) heating
The ability to separate individual defects lying closely together is called
a) sensitivity
b) resolution
c) angular acuity
d) linearity
b) resolution
In pulse-echo testing there is an advantage to using short pulses to excite the transducer because
a) the dead zone is decreased
b) the frequency spectrum is broadened
c) both a and b
d) none of the above
c) both a and b
A probe specially designed to be used totally under water is called a(n) _________ probe.
a) immersion
b) bubbler
c) gap
d) contact
a) immersion
To inspect tubular products using the ultrasonic method,
a) longitudinal wave mode is used
b) shear wave mode is used
c) surface wave mode is used
d) all wave modes can be used
d) all wave modes can be used
Flaw size is often determined by
a) comparison of probe movement with change in amplitude
b) amplitude of maximum reflection
c) both a and b
d) none of the above
c) both a and b
Electrode material on the piezoelectric crystal faces, typically evaporated to about 1000 angstroms thick, is made of
a) gold
b) silver
c) chrome/gold
d) all of the above can be used
d) all of the above can be used
The 3 essential elements common to all systems that use ultrasonic devices are
a) transducers, cables, couplant
b) transducers, scopes, testpiece
c) power source, transducer, converter
d) none of the above
c) power source, transducer, converter
The normal presentation of ultrasonic signals on an ultrasonic machine used in NDT is
a) rectified form
b) RF form
c) B-scan
d) C-scan
a) rectified form
Incidence of a sound wave from a solid to a gas is considered a free boundary condition because
a) there are no particles in a gas
b) all sound is lost in transmission
c) the acoustic impedance of a gas is essentially zero
d) none of the above
c) the acoustic impedance of a gas is essentially zero
The distance from the probe face to the last main maximum on the beam axis is called the
a) near field
b) far field
c) dead zone
d) ozone
a) near field
The purpose of the IIW block is to determine
a) probe exit point
b) refracted angle
c) range (or depth scale)
d) all of the above
d) all of the above
In steel, shear wave velocity as compared to longitudinal wave velocity is about
a) twice as fast
b) the same
c) one half as fast
d) one quarter as fast
c) one half as fast
Resonance methods of thickness testing are no longer commonly used. This technique utilized
a) continuous wave oscillators
b) pulsed wave packets
c) surface waves
d) none of the above
a) continuous wave oscillators
The incremental fine gain control of the ultrasonic instrument is calibrated in
a) 1 or 2 dB increments
b) 6 dB increments
c) 20 dB increments
d) no increments, it is completely variable
a) 1 or 2 dB increments
Which is not a characteristic of ultrasound used to evaluate materials
a) attenuation
b) density
c) magnitude of echoes
d) velocity
b) density
Compared to water, the acoustic impedance of steel is
a) higher
b) lower
c) about the same
d) higher or lower depending on the wave mode
a) higher
In weld inspection, the longitudinal wave inspection of the plate adjacent to the weld is usually done using a frequency in the range of
a) 1-2 MHz
b) 2-6 MHz
c) 6-10 MHz
d) 10-15 MHz
b) 2-6 MHz
For best results detecting a defect that may be irregularly shaped and slightly off perpendicular to the beam, the wavelength used should be
a) the size of the defect
b) as small as possible
c) as large as possible to locate the defect
d) 1 MHz
c) as large as possible to locate the defect
The product of density an acoustic velocity is
a) acoustic impedance
b) electric impedance
c) specific reactivity
d) the reflection coefficient
a) acoustic impedance
The result of spherical or “cup shaped” lens on the front of an ultrasonic probe is a(n)
a) point focused beam
b) line focused beam
c) asymptotic beam
d) divergent beam
a) point focused beam
Boron, aluminum oxide and sapphire are often used in transducers as
a) tuning transformers
b) electrodes
c) wear faces
d) none of the above
c) wear faces
Given a 2.5 MHz transducer radiating ultrasound into glycerin, what is the wavelength of the shearwave in the glycerin?
a) 2.3 mm
b) 3.2 mm
c) insufficient information provided
d) none of the above
d) none of the above
Magnetostrictive principles can be used
a) for transmitting ultrasound
b) for receiving ultrasound
c) both a and b
d) none of the above
c) both a and b
A longitudinal wave generating transducer will have a given near field in steel. If in water the near field for this probe will be
a) the same distance
b) about half as long
c) about 1/4 as long
d) about 4 times as long
d) about 4 times as long
Elastic waves can be transmitted in
a) air
b) water
c) solids
d) all of the above
d) all of the above
The use of flat bottom holes for a reference standard when testing forgings is a reasonable method of flaw assessment because
a) they provide good reflectivity at all angles
b) of their ease of manufacturing
c) a single block is required for all calibrations
d) they are a good representation of the flat defects found in forgings
d) they are a good representation of the flat defects found in forgings
The distance between successive points of impingement of the beam axis on the entry surface after reflecting from the opposite side is called
a) stand-off
b) skip distance
c) sound path
d) none of the above
b) skip distance
For flaws immediately below the surface the best option is
a) TR or twin crystal probes
b) single crystal probes
c) multi probe configurations
d) through wall testing
a) TR or twin crystal probes
The imaginary line that connects all the points of the same phase in a wave propagating in a medium is referred to as the
a) phase line
b) wave front
c) interphase index
d) refractive index
b) wave front
If a sound beam is incident on steel from water at 20 degrees, the refracted transverse wave will have an angle
a) greater than 20 degrees
b) less than 20 degrees
c) about 20 degrees
d) that cannot be determined
a) greater than 20 degrees
Backing materials used in ultrasonic transducers are used for
a) changing frequency bandwidths
b) focusing the beam
c) de-focusing the beam
d) none of the above
a) changing frequency bandwidths
Maximum sensitivity of a transducer is found at the
a) probe surface
b) test surface
c) end of the near zone
d) end of the dead zone
c) end of the near zone
Variations in a probes’ actual frequency and its nominal frequency by as much as 5%
a) put the probe “out of spec”
b) have significant effects on test results
c) are acceptable in NDT
d) none of the above
c) are acceptable in NDT
The change from longitudinal to transverse waves (and visa versa) at a boundary is called
a) Snell’s law
b) mode conversion
c) reciprocity
d) reversal
b) mode conversion
When using the large IIW Block #1, what are the fewest number of reflections you would need to use to calibrate a longitudinal probe for 100mm range?
a) 1
b) 2
c) 4
d) 8
b) 2
X-cut quartz crystal transducers are cut with active element face at right angles to the
a) X-axis
b) Y1-axis
c) Y2-axis
d) Z-axis
a) X-axis
The angle of divergence is
a) constant for a given piezoelectric material
b) applicable to the far zone only
c) increases with increasing probe dimensions
d) decreases with increasing wavelength
b) applicable to the far zone only
The size and shape of ultrasonic probes used are determined primarily by
a) the level II operator
b) the specific application
c) expected defect type and orientation
d) whether contact or immersion methods are used
b) the specific application
Probes used in ultrasonic contact testing are checked periodically for performance when in regular use. Which characteristic would not be checked daily?
a) probe index
b) beam angle
c) beam profile
d) overall system gain
c) beam profile
In hardcopy presentations of C-scans, the item recorded is
a) a absence of signal
b) the presence of a signal
c) the depth of a signal
d) a or b
d) a or b
The critical angle for the longitudinal wave is also called the
a) right angle
b) snell angle
c) first critical angle
d) second critical angle
c) first critical angle
The maximum displacement of a particle from its point of rest in a sound wave is its
a) velocity
b) amplitude of movement
c) frequency
d) wavelength
b) amplitude of movement
Threshold adjustment is applied to
a) RF display of signals
b) “clean up” the noise on the baseline
c) both a and b
d) none of the above
b) “clean up” the noise on the baseline
Focusing of ultrasound energy is accomplished by
a) lenses
b) shaping ceramic transducers
c) test piece geometry
d) all of the above
d) all of the above
In nondestructive testing the acronym EMAT stands for
a) electromagnetic acoustic transducer
b) electrically metered automatic testing
c) energy modulated acoustic technique
d) engineers make assessment tough
a) electromagnetic acoustic transducer
When establishing the relative sensitivity of higher power longitudinal wave probes on the methyl polymethacrylate insert of the IIW block
a) the total number of echoes is noted
b) the amplitude of the last echo is noted
c) the gain setting is noted
d) both a) & b)
d) both a) & b)
In general, the result of two waves interacting on each other can be found by
a) strobe lighting
b) vector addition
c) cross-multiplying
d) linear summation
b) vector addition
When testing thick specimens, it may be advisable to
a) decrease the pulse repetition frequency
b) add reject
c) change to a higher frequency
d) use a delay line prob
a) decrease the pulse repetition frequency
Which of the following terms is not used to describe methods of coupling ultrasonic energy into a test specimen?
a) non-invasive
b) direct contact
c) immersion
d) gap
a) non-invasive
The control on an ultrasonic machine which enables electrical signals to be decreased by known values, usually dB, is called a(n)
a) attenuator
b) matching box
c) reject control
d) damping control
a) attenuator
Using an unrectified A-scan presentation the dominant frequency can be determined provided you know the
a) sound path to the reference reflector
b) nominal probe frequency
c) time interval on the baseline
d) none of the above
c) time interval on the baseline
The common metric term Hertz (abb.Hz) is used to indicate
a) wavelength
b) velocity of sound
c) cycles per second
d) acoustic impedance
c) cycles per second
The smallest distance between two points on an elastic wave where the particles are in the same state of motion is the
a) period
b) wavelength
c) frequency
d) hypotenuse
b) wavelength
In a longitudinal wave, zones of compression alternate with ________ zones.
a) dead
b) rarified
c) subduction
d) anticline
b) rarified
Reflection and refraction phenomenon are illustrated in geometric-optic treatment of ultrasound by means of
a) mirrors
b) equations
c) rays and straight lines
d) none of the above
c) rays and straight lines
Gain and attenuator controls on an ultrasonic machine are usually calibrated in
a) arbitrary units
b) volts
c) decibels
d) none of the above
c) decibels
When scanning a test plate with angle beam probes, the operator can often determine the front and backwall position on the screen from
a) “grass mounds”
b) gates
c) the distance amplitude correction curve
d) none of the above
a) “grass mounds”
With a sound velocity of 1.5mm/µs in water, the wavelength of the ultrasonic disturbance in water provided by an ultrasonic cleaning machines’ 40 kHz transducer is
a) 26mm
b) 26cm
c) 3.7mm
d) 37mm
d) 37mm
If the beam from an unfocused probe strikes a concave steel surface with normal incidence from water it will
a) increase beam width
b) decrease beam width
c) be totally converted to surface waves
d) none of the above
b) decrease beam width
The probe movement that maintains a constant distance from an indication while varying the direction of the beam is called
a) orbiting
b) pivoting
c) traversing
d) lateral movement
a) orbiting
In ultrasonic testing, the distance travelled along the beam axis is called
a) beam path length
b) stand-off
c) corrected distance
d) none of the above
a) beam path length
Electromagnetic acoustic transducers (EMATs) are made from
a) silicon chips
b) ferro-magnetic crystals
c) ferro-electric crystals
d) coils of wire
d) coils of wire
To a degree, the mechanical deformation of a piezoelectric material is directly proportional to the
a) acoustic impedance of the backing
b) acoustic impedance of the piezo material
c) applied voltage
d) none of the above
c) applied voltage
Angle beam wedges can be used to generate surface waves only if
a) the refracted shear wave is 90°
b) the test piece is steel
c) the test piece is cylindrically shaped
d) none of the above
a) the refracted shear wave is 90°
Ultrasonics has been applied in
a) fish finders and measuring water depths
b) volume, channel and colour control of televisions
c) auto-focusing mechanisms in cameras
d) all of the above
d) all of the above
A probe constructed such that the ultrasonic waves converge at a point or line is a(n)
a) dual crystal probe
b) focused probe
c) de-focused probe
d) immersion probe
b) focused probe
A compression wave probe is used to generate and/or receive
a) longitudinal waves
b) shear waves
c) Rayleigh waves
d) Lamb waves
a) longitudinal waves
Scatter of ultrasound at grain boundaries is a result of
a) frequency
b) in-homogenous inclusions
c) angulation
d) differences in elastic properties
d) differences in elastic properties
Acoustic or electrical interference in ultrasonic testing is often called
a) baseline
b) noise
c) ghost echo
d) over attenuation
b) noise
The point where maximum particle displacement occurs on a standing wave is called
a) an anticline
b) an antinode
c) a node
d) a peak detector
b) an antinode
A flat normal beam probe has a near zone of 25mm in water. If used in direct contact on steel the near zone would be
a) 3mm
b) 6mm
c) 8mm
d) 12mm
b) 6mm
A positive valve of a reflection coefficient indicates
a) no phase change has occurred
b) 90 degree phase change
c) 180 degree phase change
d) an increase in amplitude
a) no phase change has occurred
Production line ultrasonic inspection of tubular test pieces is done by
a) immersion methods
b) gap methods
c) contact testing methods
d) any of the above can be used depending on the specifics of the application
d) any of the above can be used depending on the specifics of the application
Resonance peaks at frequencies of odd numbered multiples of the resonance frequency are called
a) harmonics
b) PRF
c) multiple frequencies
d) sub-harmonics
a) harmonics
The advantage of a longer path length in the standard perspex wedge of a common contact-angle beam transducer is
a) improved near surface resolution
b) better impedance matching
c) higher sensitivity to small defects
d) all of the above
a) improved near surface resolution
Phase reversal of an ultrasound wave upon reflection from a sonically softer material is indicated by
a) a zero R value
b) a negative R value
c) an R value greater than 1
d) increased resonance
b) a negative R value
When using the IIW Block #1, the probe exit point is established using the
a) 1.5mm diameter hole
b) 100mm radius
c) 50mm diameter hole
d) perspex insert
b) 100mm radius
In ultrasonic testing, attenuation studies are
a) used to study some properties of materials
b) used only in destructive tests
c) only useful when using longitudinal wave mode
d) never used
a) used to study some properties of materials
In immersion testing you would normally position the
a) main bang on the left edge of the CRT
b) entrance echo on the left of the CRT
c) first backwall on the right edge of the CRT
d) none of the above
b) entrance echo on the left of the CR
The advantage of quartz crystals over ceramic materials for ultrasonic transducers is
a) high curie temperature
b) its harness and ability to take a high polish
c) both a and b
d) there are no advantages of quartz over ceramics
c) both a and b
Ultrasonic pulse-echo techniques are used on livestock to
a) establish fat profiles
b) modify behaviour
c) increase reproductive capability
d) all of the above
a) establish fat profiles
