Neutron imaging: A non-destructive tool for materials testing. Report of a coordinated research project 2003-2006

The enhancement of utilization of research reactors is one of the major objectives of the IAEA's project on Effective Utilization of Research Reactors. In particular, the improvement of existing installations for neutron imaging and the effective utilization of such facilities are intended. From the experience of Type A facilities, it is obvious that some investment is required to come from simple neutron imaging methods (film, track-etch foils) to the more enhanced ones. Related to the installation and operation of the whole reactor system, the volume of the investment for an imaging device is minor. Also compared to the installations for neutron scattering research, neutron imaging systems are relatively cheap, but very efficient in the use of the neutrons. Therefore, one of the aims of the CRP was to look for adapted solutions for the individual reactor installation and beam line. Specific Research Objectives: To optimize the neutron beams for imaging purpose using modern simulation techniques; To enhance the beam intensity using modern layout principles, neutron optics, like focusing and beam guides and filters; To develop a standardized, low cost, neutron image grabber and analyzer for efficient data collection that can be used with low intensity sources; To improve signal processing techniques used in neutron imaging applications. Expected Research Outputs: Neutron radiography is used at research reactor centres in many Member States, but the facilities are not optimized for attractive potential applications. This fact has been brought out at various discussion meetings. The CRP is aimed at improving the design of beam lines in terms of neutron collimation and intensity; Improvements in resolution are normally achieved at a cost in intensity. For an instrument exhibiting good resolution, one needs to employ a fast counting system. It is proposed to work along these lines to develop an optimised detection system. Many facilities, at present, have small CCD systems, but they are not optimised. The experience of advanced facilities will be used to optimise their operation. Optimisation should result in additional applications and/or increased utilization of neutron radiography; This CRP will help to expand the knowledge and understanding of various neutron radiography imaging techniques and their applications among the research reactor community in developing Member States and will be helpful in training qualified neutron radiography specialists who, in addition to operating existing facilities, will be able to take up developmental work in future; The programme will help in building long term relationships between scientists from developing and developed countries. This will help in encouraging further bilateral and/or multilateral collaborations among institutions/reactor facilities in various Member States.