the back-surface reflection.
1. The indication on the instrument display that represents the far boundary of material being tested is
... [Show More] called:
angulation.
2. In immersion testing, the position of the transducer is often varied by a manipulator to transmit sound into the test part at various angles to the front surface. Such a procedure is referred to as:
coaxial cable
3. The technical name for the cable that connects the ultrasonic instrument to the transducer is:
calibration.
4. The process of standardizing an instrument or device by using a reference standard is called:
longitudinal wave.
5. Another name for a compressional wave is:
surface waves.
6. Another name for rayleigh waves is :
a couplant.
7. A material used between the face of a transducer and the test surface to permit or improve the transmission of ultrasonic vibrations from the transducer to the material being tested is called:
crystal.
8. The piezoelectric material in a transducer that vibrates to produce ultrasonic waves is called a
straight beam testing.
9. Ultrasonic testing of material where the probe is in direct contact with the material being tested may be:
is one of the most efficient receivers of ultrasonic energy
10. An advantage of using lithium sulfate in transducers is that it:
25 MHz transducer
12. The transducer that contains the thinnest piezoelectric crystal is a:
1 MHz
13. Penetration of ultrasonic waves in a material is normally the function of test frequency used. The greatest depth of penetration is provided by a frequency of
frequency and crystal size.
14. The amount of beam divergence from a crystal is primarily dependent on the
refraction.
15. When an ultrasonic beam passes through the interface between two dissimilar materials at an angle, a new angle of sound travel takes place in the second material due to:
two times
21. The velocity of longitudinal waves is approximately __________ the velocity of shear waves in the same material.
25 MHz
27. Under most circumstances, which of the following frequencies would result in the best resolving power?
A coarse-grained casting.
28. Which of the following materials of the same alloy is most like ly to produce the greatest amount of sound attenuation over a given distance?
initial pulse.
29. In contact testing, the entry surface indication is sometimes referred to as the:
coarse-grained material.
30. An ultrasonic instrument display pattern containing a large number of low-level indications (often referred to as grass or hash) could be caused by:
through-transmission testing
31. A test method employing two separate transducers on opposite surfaces of the material being tested is called
frequency
32. The number of complete waves that pass a given point in a given period of time (usually 1 s) is referred to as the
an interface.
33. The boundary between two different materials that are in contact with each other is called:
longitudinal wave.
34. When the motion of the particles of a medium is transverse to the direction of propagation, the wave being transmitted is called a:
25 MHz.
36. The "25 milion eycles per second" can be stated number as:
scanning.
37. Moving a transducer over a test surface either manually or automatically is referred to as:
velocity
38. A term sound waves pass through various substances is: used in ultrasonics to express the rate at which
vertical limit.
39. When an indication has reached the maximum signal height which can be displayed or viewed on the display of an ultrasonic instrument, the indication is said to have reached its:
angle beam testing.
40. An ultrasonic testing technique in which the transducer element is not parallel to the test surface is called:
0.2 and 25 MHz
44. Most commercial ultrasonic testing is accomplished using frequencies betweern:
elapsed time or distance.
45. In an A-scan presentation, the horizontal baseline represents the
amount of ultrasonic sound energy returning to the transducer
46. In an A-scan presentation, the amplitude of vertical indications on the display represents the:
1 MHz
47. Which of the following test frequencies would generally provide the best penetration in a 305 mm (12 in.) thick specimen of coarse-grained steel?
the high indication on the extreme left side of the display that represents the entry surface of the inspected part.
48. In a basic ultrasonic test pattern (A-scan) for contact testing (assuming no sweep delay is used), the initial pulse is:
laminar-type discontinuities with major dimensions parallel to the rolled surface.
49. An ultrasonic test using a straight beam contact transducer is being conducted through the thickness of a flat part such as a plate. This test should detect:
an air interface between the crystal surface and the part surface would almost completely reflect the ultrasonic vibrations
50. In ultrasonic testing, a liquid coupling medium between the crystal surface and the part surface is necessary because:
discontinuities located just beneath the entry-surface in the part being tested.
51. Near-surface resolution is a characteristic of an ultrasonic testing system that defines its ability to detect:
obtain a maximum response if the discontinuity is not originally oriented perpendicular to the ultrasonic beam.
52. During ultrasonic testing by the immersion method, it is frequently necessary to angulate the transducer when a discontinuity is located in order to:
longitudinal wave.
53. All other factors being equal, the mode of vibration that has the greatest velocity is the:
different in diameter, increasing by 0.4 mm (0.016 in.) increments from the No. 1 block to the No. 8 block.
54. On the area-amplitude ultrasonic standard test blocks, the flat-bottom holes in the blocks are:
maximum reflection from the entry surface.
55. In immersion testing, verification that the transducer is normal to a flat entry surface is indicated by:
convert a mechanical energy to electrical energy
56. A piezoelectric material can:
20000 Hz
57. Sound waves of a frequency beyond the hearing range of the human ear are referred to as ultrasonic waves or vibrations, and the term embraces all vibrational waves of frequency greater than approximately
material properties and wave type.
58. The velocity of sound waves is primarily dependent on the
obtain a common reproducible signal.
59. The primary purpose of reference blocks is to:
cause both an attenuation of sound and indications on the screen.
60. When testing by the surface wave method, patches of oil or dirt on the surface may [Show Less]