Neutron radiography equipment
The neutrons emitted by most neutron sources need to be slowed down by the reducer to become thermal neutrons, and then the collimator is used to limit the emission angle of the neutron beam, so that it is called beam irradiation, and then through the workpiece to be inspected. Record the image. Therefore, the neutron detection equipment should include a neutron source, a reducer (or moderator), a collimator, and a recording device.
Neutron source: There are many methods for generating neutrons, but the four types can be used for flaw detection: isotopic neutron source, accelerator neutron source, reactor neutron source, and neutron tubular neutron source.
Moderator: When fast neutrons enter the material, they are elastically scattered and inelastically scattered with the material nucleus, causing energy loss and being decelerated. When selecting a moderator material, not only its slowing ability but also its reduction ratio should be considered. A material with a large slowing ability but a small reduction ratio is not suitable as a moderator material due to its large macroscopic absorption cross section.
Recording device: The neutron conversion screen used for neutron beam detection absorbs incident neutrons and then directly emits certain rays that can be detected, such as charged particles or photons. The commonly used conversion screen in neutron detection is a flicker conversion screen, which produces fluorescence under neutron illumination to sensitize the film.
Conversion screen: The neutron itself hardly makes the film sensitive, so a conversion screen must be used in thermal neutron radiography.
-
Sales@hata-ndt.com -
0086-0371-86172891
