ASNT Neutron Radiography 3

Question 1

Which industrial application is MOST commonly inspected using neutron radiography that would be difficult to inspect with conventional X-radiography?

Accepted Answer

Corrosion and moisture trapped inside aircraft aluminum structures

Answer

Neutron radiography excels at detecting hydrogen-rich corrosion products and trapped moisture inside aluminum and other metallic aerospace structures because neutrons are sensitive to hydrogen while penetrating the surrounding metal easily.

Question 2

What is the purpose of the cadmium ratio measurement in a neutron beam characterization?

Accepted Answer

To determine the ratio of thermal to epithermal neutrons in the beam

Answer

The cadmium ratio is the ratio of neutron activation (or flux) measured without a cadmium filter to that measured with one; it indicates the relative proportion of thermal to epithermal neutrons because cadmium strongly absorbs thermal neutrons.

Question 3

In digital neutron radiography, which detector type directly converts neutron interactions to electronic signals with high spatial resolution?

Accepted Answer

Neutron-sensitive CCD camera coupled to a scintillating screen

Answer

A scintillating screen (such as Li-6 or Gd-based) converts neutrons to visible light, which is then captured by a CCD camera; this provides real-time, high-resolution digital neutron images.

Question 4

What is the primary function of a beam purity indicator (BPI) in neutron radiography?

Accepted Answer

To indicate the relative amount of gamma contamination in the neutron beam

Answer

A beam purity indicator (BPI) is an IQI device that reveals the extent of gamma radiation contamination in the neutron beam, since excess gamma content degrades radiographic contrast and image quality.

Question 5

According to ASNT personnel qualification guidelines, which certification level is authorized to interpret neutron radiographic results and write procedures?

Accepted Answer

Level III

Answer

ASNT Level III personnel are qualified to establish techniques, write and approve procedures, and interpret results, whereas Level II can perform and evaluate tests per written procedure and Level I performs tests under supervision.

ASNT - American Society for Nondestructive Testing, Inc. Practice Test

ASNT - American Society for Nondestructive Testing, Inc. Practice Test

ASNT Neutron Radiography 3