The UCD MNRC was developed by the U.S. Air Force to detect low level corrosion and hidden defects in aircraft structure using an imaging technique known as neutron radiography. This facility was designed primarily for this application and can handle the largest neutron radiography jobs in the world. In addition to Neutron Radiography, we also provide Neutron Tomography imaging services.

Facilities

The UCD MNRC is an ISO 9001:2000 registered facility with Level 1, 2 and 3 certified neutron radiographers. Our imaging system comprises of four neutron beam tubes, all tangential to the reactor core. The neutron beam is approximately 9 inches (22.5 cm) in diameter and has an intensity of approximately 1X10⁷ n/cm²·s. The neutron beams are highly collimated with an L/D of 50 - 400, resulting in high spatial resolution. Additionally, the neutron spectrum is highly thermalized, which allows high quality imaging.

The radioscopic systems use the CF Thompson tube as the neutron camera. This, combined with the SIT (Silicon Intensified Tube) camera, allows us to capture images at a rate of 30 frames/second.

The film neutron radiography system utilizes a Gadolinium vapor deposited screen that is 14 x 17 inches (35.5 x 43.2 cm) in size. The film cassette is a vacuum container and the film is a fine grain emulsion. This combination produces neutron images with a spatial resolutions of .001-.002 inch or 3mm-5mm.

The neutron tomography system utilizes a 1024 X 1024 pixel CCD (Charged Coupled Device) camera to image the sample and two workstations to process the data. The spatial resolution of the present system is approximately 200 microns. We are in the process of upgrading the system to 50 micron spatial resolution.

The robotic positioning systems that places the radiographic sample can accommodate items up to 34 feet (1036 cm) long, 12 feet (366 cm) high, and weighing up to 5,000 lbs (2270 kg).

The UCD MNRC has four bays to perform neutron imaging activities. Each bay has a different capabilities and specifications as highlighted in the table below:

These bays are optimized for production use, allowing us to process samples in relatively short times.

We are constantly improving our facilities and are planning for the following system upgrades:

• New video cameras in bay 1 and bay 2 to improve frame rates.
• Move from x-ray film to film-less radiography. This will allow us to produce all images digitally.
• Development of a neutron imaging microscope that will provide spatial resolution of ~ 10 microns.
• Development of a system that uses multi-channel detector plates that will provide spatial resolutions from 50 microns to 20 microns.