High frequency sound waves are very directional, and they will travel through a medium (like a piece of steel or plastic) until they encounter a boundary with another medium (like air)

Ultrasonic nondestructive testing, also known as ultrasonic NDT or simply UT, is a method of characterizing the thickness or internal structure of a test piece through the use of high frequency sound waves.

The effective permeability is a parameter that depends entirely on the frequency ratio, and the effective permeability determines the distribution of eddy currents and magnetic field strengths in the specimen.

The method is based on the same principle as medical radiography in a hospital. A piece of radiographic film is placed on the remote side of the material under inspection and radiation is then transmitted through from one side of the material to the r

Radiographic Testing (RT or X-ray or Gamma ray) is a non-destructive testing (NDT) method that examines the volume of a specimen.

When the primary coil and the secondary coil (the object to be inspected) are coupled to each other, an induced current is generated in the closed secondary coil due to the mutual inductance, which in turn affects the voltage and current in the primar