Electromagnetic Acoustic Transducer (EMAT) Magnet
 ---- For NDT(Nondestructive testing) transducer magnet design

Electromagnetic acoustic transducer (for short EMAT) is a new ultrasonic transmitting and receiving device. It is generated by an electromagnetic coupling method and receiving ultrasonic waves. EMAT is working with a non-contact, no coupling agent, does not require pre-treatment of the workpiece and many other advantages, the majority of attention nondestructive testing and evaluation workers, and effectively extends the application field of ultrasonic NDT techniques.

EMAT transducers mechanism based on the nature of the workpiece material are mainly three kinds of forms: Lorentz force, magnetostrictive force and magnetizing force. In the non-ferromagnetic materials, the Lorentz force plays a major role; in ferromagnetic materials, the three mechanisms together and magnetostrictive force the most significant. Magnet in this device is a very important element! It plays a decisive role. Currently a magnet for customers to choose is high-performance NdFeB permanent magnets and SmCo permanent magnet.

There are three elements of the EMAT:
(1) Magnet (a permanent magnet or an electromagnet for providing a magnetic field),
(2) High-frequency coil (for generating a high-frequency excitation magnetic field),
(3) Workpiece (detection object, is an indispensable part of EMAT).

Experts contrast bar magnet and the permanent magnet assembly by  Photographic, show that the permanent magnets assembly with small size, compact structure, the magnetic flux density, magnetic field energy is concentrated, directional strong, flexible and convenient, economical.

China Magnets Source Material Ltd is experienced manufacturer for the EMAT Magnet. Our magnet quality is stable. And we have been cooperating with EMAT manufacturers from Russia, Germany over 7 years, supplying the magnets material for them.

At present, the foreign countries have entered the industrial application stage electromagnetic ultrasonic technology, it is foreseeable in the near future EMAT technology will become the mainstream in the field of non-destructive testing technologies and play an irreplaceable role.