M. Berke - 02.05.2001 Krautkrämer, Hürth - Product Training 1 Basic Principles of Ultrasonic Testi Basic Principles of Ultrasonic Testi Basic Principles of Basic Principles of Ultrasonic Testing Ultrasonic Testing Theory and Practice Theory and Practice
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
M. Berke - 02.05.2001 Krautkrämer, Hürth - Product Training 1
Basic Principles of Ultrasonic TestingBasic Principles of Ultrasonic Testing
Basic Principles ofBasic Principles of
Ultrasonic TestingUltrasonic Testing
Theory and PracticeTheory and Practice
M. Berke - 02.05.2001 Krautkrämer, Hürth - Product Training 2
Basic Principles of Ultrasonic TestingBasic Principles of Ultrasonic Testing
Examples of oscillationExamples of oscillation
ball ona spring
pendulum rotatingearth
M. Berke - 02.05.2001 Krautkrämer, Hürth - Product Training 3
Basic Principles of Ultrasonic TestingBasic Principles of Ultrasonic Testing
The ball starts to oscillate as soon as it is pushed
Pulse
M. Berke - 02.05.2001 Krautkrämer, Hürth - Product Training 4
Basic Principles of Ultrasonic TestingBasic Principles of Ultrasonic Testing
Oscillation
M. Berke - 02.05.2001 Krautkrämer, Hürth - Product Training 5
Basic Principles of Ultrasonic TestingBasic Principles of Ultrasonic Testing
Movement of the ballball over time
M. Berke - 02.05.2001 Krautkrämer, Hürth - Product Training 6
Basic Principles of Ultrasonic TestingBasic Principles of Ultrasonic Testing
Time
One full oscillation T
Frequency
From the duration of one oscillation T the frequency f (number of oscillations per second) is calculated:
Tf
1T
f1
M. Berke - 02.05.2001 Krautkrämer, Hürth - Product Training 7
Basic Principles of Ultrasonic TestingBasic Principles of Ultrasonic Testing
180 36090 270Phase
Time
a
0
The actual displacement a is termed as:
sin A a sin A a
M. Berke - 02.05.2001 Krautkrämer, Hürth - Product Training 8
Basic Principles of Ultrasonic TestingBasic Principles of Ultrasonic Testing
SpectrumSpectrum ofof soundsound
Frequency range Hz Description Example
0 - 20 Infrasound Earth quake
20 - 20.000 Audible sound
Speech, music
> 20.000 Ultrasound Bat, Quartz crystal
M. Berke - 02.05.2001 Krautkrämer, Hürth - Product Training 9
Basic Principles of Ultrasonic TestingBasic Principles of Ultrasonic Testing
gas liquid solid
Atomic structuresAtomic structures
low densityweak bonding forces
medium densitymedium bonding forces
high density strong bonding forcescrystallographicstructure
M. Berke - 02.05.2001 Krautkrämer, Hürth - Product Training 10
Basic Principles of Ultrasonic TestingBasic Principles of Ultrasonic Testing
M. Berke - 02.05.2001 Krautkrämer, Hürth - Product Training 11
Basic Principles of Ultrasonic TestingBasic Principles of Ultrasonic Testing
T
distance travelled
start of oscillation
M. Berke - 02.05.2001 Krautkrämer, Hürth - Product Training 12
Basic Principles of Ultrasonic TestingBasic Principles of Ultrasonic Testing
T
Distance travelled
From this we derive:
or Wave equation
During one oscillation T the wave front propagates by the distance :
Tc
Tc f c f c
M. Berke - 02.05.2001 Krautkrämer, Hürth - Product Training 13
Basic Principles of Ultrasonic TestingBasic Principles of Ultrasonic Testing
Direction of oscillation
Direction of propagationLongitudinal wave
Sound propagationSound propagation
M. Berke - 02.05.2001 Krautkrämer, Hürth - Product Training 14
Basic Principles of Ultrasonic TestingBasic Principles of Ultrasonic Testing
Direction of oscillation
Direction of propagationTransverse wave
Sound propagationpropagation
M. Berke - 02.05.2001 Krautkrämer, Hürth - Product Training 15
Basic Principles of Ultrasonic TestingBasic Principles of Ultrasonic Testing
Wave propagationpropagation
AirWaterSteel, longSteel, trans
330 m/s1480 m/s
3250 m/s
5920 m/s
Longitudinal waves propagate in all kind of materials.Transverse waves only propagate in solid bodies. Due to the different type of oscillation, transverse wavestravel at lower speeds.Sound velocity mainly depends on the density and E-modulus of the material.
M. Berke - 02.05.2001 Krautkrämer, Hürth - Product Training 16
Basic Principles of Ultrasonic TestingBasic Principles of Ultrasonic Testing
Reflection and Reflection and TransmissionTransmission
As soon as a sound wave comes to a change in material characteristics ,e.g. the surface of a workpiece, or an internal inclusion, wave propagation will change too:
M. Berke - 02.05.2001 Krautkrämer, Hürth - Product Training 17
Basic Principles of Ultrasonic TestingBasic Principles of Ultrasonic Testing
Behaviour at an interfaceBehaviour at an interface
Medium 1 Medium 2
Interface
Incoming wave Transmitted wave
Reflected wave
M. Berke - 02.05.2001 Krautkrämer, Hürth - Product Training 18
Basic Principles of Ultrasonic TestingBasic Principles of Ultrasonic Testing