Neutron Radiography and neutron imaging solutions are a specialty of Nray Services Inc. Head Office: 56A Head Street Dundas Ontario, Canada L9H 3H7 Phone: 905.627.1302 Fax: 905.627.5022 URL:www.nray.ca  The term nray can also be spelled n-ray or NR
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N-ray vs X-ray
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N-Ray vs. X-Ray (What's the Difference?)

Neutron radiography (N-ray or NR) and X-radiography (X-ray) are complementary non-destructive testing techniques. In both cases, a form of radiation passes through the object being imaged, and then exposes a photographic film. The type of radiation used in neutron radiography is neutrons, while the type of radiation used in X-radiography is X-rays. Neutron radiographs and X-radiographs show different characteristics of the object imaged due to differences in neutron and X-ray interaction with the material that the object is made up of (see Figure 1).

The images shown below provide good examples of the differences between neutron radiography and X-radiography.

Liquids, such as the lighter fluid shown in the lighter image, plastics, rubbers, ceramics and lubricants show up very well in neutron radiographs, while metal components show up well in X-ray images. Due to the relative invisibility of metals to neutrons, neutron radiography can be used to effectively image items encased in metal. The variation in images produced using neutron radiography and X-radiography makes the two complementary technologies, both very useful
for particular applications.

Click on image below to download PDF enlargement of comparision.

Figure (a)
Liquids, such as the lighter fluid shown in the image above, as well as, plastic components, rubbers, ceramics and lubricants show up very brightly in neutron radiographs, while metals show up well in X-ray images. For this reason, neutron radiography is well suited to imaging various materials encased in metals.

Figure (b)
Internal chambers, passage ways and details in metal parts, such as the quick-disconnect fitting shown above, can be imaged very clearly using neutron radiography. x-radiography is more suited to imaging metal inclusions in other materials.

Figure (c)
The internal structure, air pathways and blockages or inclusions in metal alloy turbine blades can be imaged very clearly using neutron radiography. Even areas surrounded by several centimeter thickness material, such as the turbine blade root holes shown in the image above, can be imaged very effectively. X-radiography is more suited to imaging metals inside of other materials.

Figure 1

Figure 1 – While the probability of x-ray interaction with matter increases with the target material atomic number, the probability of neutron interaction with matter is random with respect to the target material atomic number. Neutron attenuation by matter depends on the material properties, specifically the neutron cross-section.