Section 2: Physics of Ultrasound

Transverse wave can be introduced into the test material by various methods:
1. Inclining the incident L-wave at an angle beyond the first critical angle, yet
short of second critical angle using a wedge.
2. In immersion method, changing the angle of the normal search unit
manipulator,
3. Off-setting the normal transducer from the center-line for round bar or pipe.
for 45° refracted transverse wave, the rule
of thumb is the offset d= 1/6 of rod diameter