Design, Construction, and Demonstration of the Colorado School of Mines Neutron Imaging Facility

The MInes NEutron Radiography facility (MINER facility) installed at the United States Geological Survey TRIGA Reactor provides new capabilities for both researchers and students at the Colorado School of Mines. The facility consists of a number of components, including a neutron beamline and beamstop, an optical table, an experimental enclosure and associated interlocks, a computer control system, a microchannel plate imaging detector, and the associated electronics.

Radiographs of a sensitivity indicator - a resolution indicator developed by the American Society for Testing and Materials - taken using both the digital detector and the transfer method provide one demonstration of the radiographic capabilities of the new facility. Calibration fuel pins manufactured using copper and stainless steel surrogate fuel pellets provide additional specimens for demonstration of the new facility and offer a comparison between digital and film radiography at the new facility. The calibration pins contain simulated defects of known dimensions, including pellet-clad gaps, gaps between pellets, and central voids within the pellets. Comparison of the radiographs taken by the two methods reveals that the digital detector does not produce high-quality images when compared to film radiography. Additionally, there are a number of artifacts in the digital images produced by the image acquisition system. The quality of the film images demonstrates that the problems with the digital images are a product of the digital imaging system and not the neutron beam.