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33 Cards in this Set
- Front
- Back
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Frequency |
the Number of oscillations made by each particale in one second |
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cycle |
the distance between to equivalent points on the sine wave |
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Sine |
Equal to the ratio of the side opposite |
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Amplitude |
the maximum displacement from the base line |
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Human range of Hearing |
16 cycles to 20,000 cycles per second |
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Ultrasonic vibration range |
20,000 cycles and above |
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Elasticity |
resistance to tension or compression of the Material |
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Compression wave |
longitudinal |
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transverse wave |
Shear ware |
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Velocity |
The speed sound travels through a medium |
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Velocity depends on |
the density and elasticity of the material |
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Wavelength calculation |
velocity divided by frequency |
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Acoustic impedance |
the product of velocity of sound in the Material and the density of the material |
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Second critical Angle |
second critical angle is reached when the refracted shear bean angle reaches 90° |
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First Critical Angle |
The first Critical angle is reached when the fracted longitudinal beam reaches 90° |
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Mode conversion |
when sound is reflected off an object or defect and bounces in every direction |
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Piezo- Electric effect |
the ability to generate electrical charges and generate mechanical vibrations |
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most effective transmitter of sound |
Lead Zirconate Titanate (PZT) usually used in immersion testing |
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Best receiver of sound |
Lithium Sulphate |
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most commonly used transducer Material |
Barium titanate |
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Dampening |
controlling the pulse length |
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the thicker the crystal |
the higher the resonant frequency |
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Absorption |
the lose of energy due to moving vi bra ting molecules |
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A Lower frequency will help with |
a materia l that has high absorption and scatter |
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Attenuation decreases |
as test Frequency decreases |
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penetration increases |
as frequency decreases |
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Sensitivity decreases |
as frequency decreases |
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nearfield ca lculation |
Transducer dia squared divided by 4x the wavelength |
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Intensity is effected by Beam spread by |
Doubling the distance from the probe the intensity is decreased by 1/4 the original valve |
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Beam index point |
the point sound exits the transducer wedge |
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Skip distance |
the distance along the surface from the Beam index point where sound returns to the exam surface. The bottom of the triangle. |
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penetration depth of a surface wave |
one wavelength |
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S and R Value |
Size at R Reject at S |
