Development of Cold Neutron Radiography Facility (CNRF) based on China Mianyang Research Reactor (CMRR)

摘要

To carry on neutron imaging researches (radiography/tomography), we built a Cold Neutron Radiography Facility (CNRF), based on the China Mianyang Research Reactor (CMRR) at Institute of Nuclear and Chemistry (INPC). This CNRF system utilizes cold neutrons from the C1 neutron guide. The facility consists of beam shutter, flight tubes, beam limiter, object handling system, imaging system, beam stop and data acquisition system. The maximum neutron flux at the sample position is 6 × 10~6 n/cm~2/s, approximately. There are seven pinholes in the collimator system, to offer a possible L/D from 200 to 1300. With different imaging lenses, the imaging system could provide four different FOVs. The performance parameters are tested by Siemens Star and ASTM standard devices-beam purity indicator (BPI) and image sensitivity indicator (SI). Our results show the resolution of CNRF is better than 20 μm (i.e. 251p/mm), and its typical radiography image is of Category-I, as defined in ASTM E545.