Ultrasonic Testing (UT) Review Questions Flashcards
1
Q
1. Ultrasonic waves propagate through test materials in the form of: A. Electromagnetic waves B. Low-voltage electric fields C. Discontinuous radio waves D. Mechanical vibrations
A
D. Mechanical vibrations
2
Q
2. When an ultrasonic beam passes through the interface of two dissimilar materials at an angle, a new angle of sound travel takes place in the second material due to: A. Attenuation B. Rarefraction C. Compression D. Refraction
A
D. Refraction
3
Q
3. The gradual loss of energy as ultrasonic vibrations travel through material is referred to as: A. Reflection B. Refraction C. Compression D. Attenuation
A
D. Attenuation
4
Q
4. Ultrasonic velocities are different for different materials. These differences are primarily caused by differences in the materials: A. Frequency and wavelength B. Thickness and travel time C. Elasticity and density D. Chemistry and permeability
A
C. Elasticity and density
5
Q
- Ultrasonic energy for immersion testing is transmitted to the test object as a compressional wave because:
A. Compressional waves travel faster and will therefore reduce the distance of the interface signal
B. Liquids will only sustain compressional waves
C. Compressional waves are used with immersion testing only
D. The higher intensity of compressional waves is necessary to overcome high attenuation in liquids
A
B. Liquids will only sustain compressional waves
6
Q
6. When inspecting corse-grained materials, which of the following frequencies will generate a sound wave that will be most easily scattered by the grain structure? A. 1.0 MHz B. 2.25 MHz C. 5 MHz D. 10 MHz
A
D. 10 MHz
7
Q
- In general, shear waves are more sensitive to small discontinuities than longitudinal waves for a given frequency and in a given material because:
A. The wavelength of shear waves is shorter than the wavelength of longitudinal waves
B. Shear waves are not easily dispersed in the material
C. The direction of particle vibration for shear waves is more sensitive to discontinuities
D. The wavelength of shear waves is longer than the wavelength of longitudinal waves
A
A. The wavelength of shear waves is shorter than the wavelength of longitudinal waves
8
Q
8. The ability of transducers to detect echoes from small discontinuities is a definition of? A. Resolution B. Sensitivity C. Definition D. Gain
A
B. Sensitivity
9
Q
9. Which of the following will create a resonance condition in a specimen? A. Pulsed longitudinal waves B. Continuous longitudinal waves C. Pulsed shear waves D. Continuous shear waves
A
B. Continuous longitudinal waves
10
Q
10. The display on most basic pulse-echo ultrasonic instruments consists of: A. Automatic read-out equipment B. An A-scan presentation C. A B-scan presentation D. A C-scan presentation
A
B. An A-scan presentation
11
Q
11. In a basic pulse-echo ultrasonic instrument, the component that produces the voltage that activates the search unit is called? A. An amplifier B. A receiver C. A pulser D. A synchronizer
A
C. A pulser
12
Q
- The primary purpose of reference blocks is to:
A. Aid the operator in obtaining maximum back reflections
B. Obtain the greatest sensitivity possible from an instrument
C. Obtain a common reproducible reference standard
D. Establish the size and orientation of a discontinuity
A
C. Obtain a common reproducible reference standard
13
Q
- The general use of distance-amplitude correction is to compensate for:
A. Amplitude of noise siganls
B. Velocity changes
C. Vertical nonlinearity in the ultrasonic instrument
D. Attenuation, distance and beam spread
A
D. Attenuation, distance and beam spread
14
Q
- In area-amplitude ultrasonic standard test blocks, the flat bottomed holes in the blocks are:
A. All the same diameter
B. Different in diameter, increasing in 0.4 mm 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
A
B. Different in diameter, increasing in 0.4 mm increments from the No. 1 block to the No. 8 block
15
Q
15. The amount of energy reflected from a discontinuity is dependent on all the following except the: A. Size of the discontinuity B. Orientation of the discontinuity C. Type of the discontinuity D. Test frequency
A
D. Test frequency
16
Q
16. The presence of a discontinuity will not produce a specific discontinuity indication on the CRT screen when which of the following techniques is used? A. Straight-beam testing B. Surface-wave testing C. Angle-beam testing D. Through-transmission testing
A
D. Through-transmission testing
17
Q
- Lack of parallelism between the entry surface and the back surface:
A. May result in a screen pattern that does not contain back reflection indications
B. Makes it difficult to locate discontinuities that lie parallel to the entry surface
C. Usually indicates a porous condition existing in the metal
D. Will decrease the penetrating power of the test
A
A. May result in a screen pattern that does not contain back reflection indications
18
Q
- Significant errors in ultrasonic thickness measurement can occur if:
A. Test velocity is varied
B. The velocity of propagation deviates substantially from an assumed constant value for a given material
C. Water is used as a couplant between the transducer and the part being measured
D. Longitudinal waves are used
A
B. The velocity of propagation deviates substantially from an assumed constant value for a given material
19
Q
- In contact testing, shear waves can be induced in the test material by:
A. Placing an X-cut quartz crystal directly on the surface of the material and coupling through a film of oil
B. Using two transducers on opposite sides of the test specimen
C. Placing a spherical acoustic lens on the face of the transducer
D. Using an angle-beam transducer with the transducer mounted on a plastic wedge so that sound enters the part at an angle
A
D. Using an angle-beam transducer with the transducer mounted on a plastic wedge so that sound enters the part at an angle
20
Q
- The most commonly used method of producing shear waves in a test part when inspecting by the immersion method is by:
A. Transmitting longitudinal waves into a part in a direction perpendicular to its front surface
B. Using two crystals vibrating at different frequencies
C. Using a low-frequency transducer
D. Angulating the search tube to the proper angle with respect to the entry surface of the test part
A
D. Angulating the search tube to the proper angle with respect to the entry surface of the test part
21
Q
- In immersion testing, proof that the search unit is normal to a flat entry surface is indicated by:
A. Maximum reflection amplitude from the entry surface
B. Elimination of water multiples
C. Maximum reflection amplitude from the back surface
D. Maximum amplitude of the initial
A
A. Maximum reflection amplitude from the entry surface
22
Q
- In immersion testing, the water distance between the search unit and the test piece:
A. Should be as small as possible
B. Will have no effect on the test
C. Should be the same as the water distance used during calibration
D. Should be as great as possible
A
C. Should be the same as the water distance used during calibration
23
Q
- Generally, the best ultrasonic testing technique for detecting discontinuities oriented along the fusion zone is a welded plate is
A. An angle-beam contact method employing surface waves
B. An immersion test using surface waves
C. A resonance technique
D. An angle-beam method using shear waves
A
D. An angle-beam method using shear waves
24
Q
- Thin sheet may be inspected for laminar discontinuities with the ultrasonic wave directed normal to the surface by observing:
A. The amplitude of the front surface reflection
B. The multiple reflection pattern
C. The amplitude of the initial pulse
D. Signals that “walk” or move along the time basis as the transducer is scanned over the sheet
A
B. The multiple reflection pattern
25
Q
- Ultrasonic inspection of castings is occasionally impractical because of:
A. Extremely small grain structure typical in castings
B. Coarse grain structure
C. Uniform flow lines
D. Random orientation of discontinuities
A
B. Coarse grain structure
26
Q
- Angle beam testing of plate will often miss:
A. Cracks that are perpendicular to the sound wave
B. Inclusions that are randomly orientated
C. Laminations that are parallel to the front surface
D. A series fo small discontinuities
A
C. Laminations that are parallel to the front surface
27
Q
27. Reflection indications from a weld being inspected by the angle-beam technique may represent all of the following except: A. Porosity B. Cracks C. The weld bead D. Laminations in the base metal
A
D. Laminations in the base metal
28
Q
- An ultrasonic test using a straight-beam contact search unit is being conducted through the thickness of a flat part, such as plate. This test should detect:
A. Laminar type flaws with major dimensions parallel to the plane of the rolled surface
B. Transverse type flaws with major dimensions at right angles to the plane of the rolled surface
C. Radial flaws with major dimensions along the length but radially oriented to the rolled surface
D. Rounded flaws at the edges of the rolled plate
A
A. Laminar type flaws with major dimensions parallel to the plane of the rolled surface
29
Q
- The resonance technique of thickness measurement has been mostly replaced by:
A. Through-transmission longitudinal wave techniques
B. Acoustic emission monitoring
C. Pitch-and-catch shear-wave techniques
D. Linear time-based pulse-echo techniques
A
D. Linear time-based pulse-echo techniques
30
Q
30. Ultrasonic testing techniques are useful in testing laminate and sandwich construction test objects for: A. Paint thickness B. Bond integrity C. Leakage D. Surface roughness
A
B. Bond integrity
31
Q
- Ultrasonic techniques are frequently used in in-line automated process control applications to measure and control:
A. Moisture content in food
B. Surface roughness of turbine blade castings
C. Chemical activity in chemical etching processes
D. The thickness of cold-rolled strips, sheets and plates
A
D. The thickness of cold-rolled strips, sheets and plates
32
Q
- Which of the following statements about field inspection applications of ultrasonic testing is true:
A. Because the equipment is large and bulky, field inspections are difficult at best
B. Aircraft and other field maintenance inspections usually require three persons: one to manipulate the transducer, one to monitor the instrument and one to record results
C. Digital displays must be used for outdoor inspection because of the limited brightness of CRT displays
D. Manual and automatic systems can be used for field inspection
A
D. Manual and automatic systems can be used for field inspection
