ULTRA SONIC TESTING

                                                     PART 1

 ULTRA- SUPER

SONIC- CONNECTED WITH WAVES

1=INFRASONIC SOUND RANGE < 20 Hz (Hertz)

2=ULTRASONIC SOUND RANGE >20 KHz

3=SONIC SOUND RANGE 20Hz- 20 KHz 

                                                    WAVE PROPAGATION

1- LONGITUDINAL WAVES

           ---particles movement is in the direction of waves.

           ---can travel both in liquids and solids.

2- SHEAR WAVES/TRANSVERSE WAVES

          ----particle movement is perpendicular to the direction of                         wave.

          ----only travel in liquids.

3- SURFACE WAVES

         ---- combined motion of longitudinal & shear waves.

4- PLATE WAVES/LAMB WAVES

         ----similar to surface waves

         ----only for thin plates(few wavelength in thickness)