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Neutron backscattering nondestructive-test instruments
Several resolution functions are analysed in order to describe the unsharpness of knife-edge images. Comparisons are done with the definition of unsharpness by various authors. The suitablity of a resolution function is assessed according to its fit to the data from measured densities. Investigations of the dyprosium transfer method, the track etch technique and the Gadolinium direct method were conducted in each case distinguishing between inherent and geometrical ansharpness. 38815
Windsor, C.G.
The nature of the scattering process in small angle neutron scattering United Kingdom Atomic Energy Authority, Harwell, A E R E - M P D NBS-342, 16 pp. (May 1988) Neutron and X-ray small angle scattering provide, along with electron microscopy and diffraction, the principal tools for the microscopic characterisation of materials. Neutron, X-ray and electron beams have quite different properties. In fact, each has unique advantages. The penetration of neutrons through most materials is responsible for many of its applications. The ever increasing intensity of available X-ray beams is opening new fields. The advantage of electron beams is their ability to work in both real and reciprocal space. The problems of transforming the results of an experiment in reciprocal space to give an interpretation in real space are central to small angle scattering, and will be discussed in detail. Several examples will be given of the successful use of small angle neutron and X-ray scattering applied to problems where other techniques have failed to make a decisive contribution. 38812
Heidt, H.; Stade, J.
State and prospects of industrial neutron radiography in Germany (In
German) Materialprnfung, Vol. 30, No. 5, pp. 137-139 (May 1988) Although the first neutron radiographies in Germany were made nearly 50 years ago, this nondestructive testing method has not yet been widely used in industry. The main reason is the lack of mobile, intensive and low-cost neutron sources. Another important aspect is the availability of real-time inspection systems equipped with neutron image amplifiers which will accelerate the test and permit to represent dynamic processes. New applications for mobile neutron sources may be expected in aircraft inspection, in testing fibre-reinforced plastics, in different types of ceramic materials, in the building sector, in corrosion protection as well as with various problems encountered with lubrication agents.
38807 Pekarskii, G.Sh. Neutron backscattering nondestructive-test instruments Soviet Journal of Nondestructive Testing, Vol. 23, No. 7, pp. 512-515 (Mar. 1988) Calculations and measurements are used to make recommendations for neutron nondestructive testing and radioisotope automatic devices operating with one-sided access. Emphasis is placed on optimizing the major components for particular industrial purposes. Operating characteristics are given for various instruments: thickness gauges, level gauges, and means of detecting blocking points in pipe-lines, etc. 38625
McCauley, J. W.
NDT: Clearing the reliability bottleneck Ceramic Industry, Vol. 130, No. 3, pp. 33-34 (Mar. 1988) Nondestructive testing will play an important role in both the production of ceramic parts and flaw detection to improve their present low reliability, as they are more widely used in industry. A wide variety of nondestructive testing techniques, appropriate to different ceramic problems are listed, with ultrasonic, radiography, optical methods and neutron scattering being of most benefit for both green- state and sintered ceramics. 38526
Panakkal, J.P.; Ghosh, J.K.
A simple model for neutron radiography of uranium-plutonium mixed oxide fuel pins Journal of Nuclear Materials, Vol. 153, No. 1-3, pp. 82-85 (Apr. 1988) Neutron radiography has been used for monitoring plutonium enrichment in uranium-plutonium mixed oxide fuel pellets, inside welded nuclear fuel pins, by correlating the optical density of radiographs at the centre of the pellets and plutonium enrichment. Optical density data corresponding to different thicknesses of the pellets starting from the centre towards the periphery was generated by microdensitometer scanning of neutron radiographs of the experimental fuel pins. An attempt has been made to correlate the optical density at points corresponding to different thickness segments of the pellets and thermal neutron interaction probability (product of the total macroscopic neutron cross section and the distance traversed by the neutrons). Based on the experimental data generated, a simple model for transmission of neutrons through nuclear fuel pins has been evolved. Using this model, it is possible to predict the optical density of plutonium bearing fuel pins containing pellets of different composition or diameter in neutron radiographic investigations. 38517
Ratcliffe, B.J.
Investigation into the use of track-etch imaging to produce neutron radiographs from a non-reactor neutron source British Journal of Nondestructive Testing, Vol. 30, No. 3, pp. 183-188 (May 1988) A study is described of the use of cellulose nitrate with an enriched boron-10 converter screen for producing neutron radiographs from a RARDE non-reactor neutron assembly. Investigation into the required exposure and etching times has been made together with the measurement of unsharpnesses. The study shows that track-etching gives a sharper image than that obtained with
NDT International August 1989
the dysprosium transfer technique and the image is available for viewing in a much shorter time.
Lambrineas, P.; Finlayson, T.R.; Griffiths, J.R.; Howard, C.J.; Smith, T.F.
38220
Neutron diffraction residual stress measurements on a thin steel plate N D T International, Vol. 20, No. 5, pp. 285-290 (Oct. 1987) Residual stress measurements are made on a thermally stressed steel plate (4 mm thick) by using neutron diffraction. The sin/sup 2/psi technique, commonly employed to measure residual stresses by using X- ray diffraction, is applied to show that the stresses are biaxial, lying within the plane of the plate, and to evaluate the magnitude of the stresses. Measurements are made in both transmission and reflection geometries. Stress measurements made in a particular sample orientation are reproducible to within + - 10 MPa. The principal stresses determined from a series of such measurements have an uncertainty of + - 30 MPa, which is comparable to the + - 20 MPa commonly quoted for the X-ray sin/sup 2/psi technique. 38217 Brenizer, J.S.; Tobin, K.W.; Hylko, J.M.; McRae, D.D.; Jenkins, R.W. Jr. Quantitative measurement of equivalent water density in a burning
cigarette Materials Evaluation, Vol. 45, No. 11, pp. 1310-1314 (Nov. 1987) As a result of an ongoing attempt to quantify the deposition of hydrogenous compounds along the axial direction of a burning cigarette, software has been developed that takes into account the statistical nature of the neutron imaging system. This allows small variations in pixel luminance to be recorded in real time during the burn and correlated to an equivalent water density. The data collection process is based on spatial grouping of pixel locations within the rod as well as a time-averaged input of these discrete pixel groups. Once the system has been calibrated, a cigarette is positioned in the neutron beam. The area of interest is then divided into ten equal parts. All the pixel luminances in an area are averaged into one representative luminance value. As the cigarette burns, these areas are simultaneously sampled. A statistical analysis is performed for the real-time averages, and the data are stored in a file for later analysis. 38212
Ratcliffe, B.J.
Development of a non-reactor neutron radiographic assembly using a 12 MeV linear electron accelerator British Journal of Nondestructive Testing, Vol. 30, No. 2, pp. 94-98 (Mar. 1988) A description is given of the development of a neutron radiography assembly which does not use a nuclear reactor. The neutron radiographic technique developed can in some circumstances detect explosive in metal ordnance with a greater sensitivity than X- radiography. 38211
Mayers, J.; Baciocco, G.; Hannon, A.C.
Temperature measurement by neutron resonance radiography Rutherford Appleton Laboratory, Didcot (United Kingdom), RAL-88-017, 14 pp. (Mar. 1988) We present a new data analysis technique for obtaining temperatures from neutron resonance radiography measurements. The technique is applied to measurements on tantalum and rhenium foils, a high temperature engineering alloy and a model catalytic system. Temperatures have been obtained to an accuracy of better than + - 1 C in the temperature range 21 C to 600 C. The results, are in good agreement with theoretical simulations. 38210
Orphan, V.J.; Maung, T.
Robotic aircraft scanner for neutron radiographic inspection Proceedings of the 35th Conference on Remote Systems Technology, Los Angles, California (United States), Nov. 1987. pp. 195-199 American Nuclear Society, 1988. A robotic positioner and manipulator, a key component of a Mobile Neutron Radiography System (MNR) for aircraft inspection, is described. The MNRS is designed to inspect military aircraft for hidden corrosion in aluminum structures. MNRS is comprised of an accelerator-based (Kaman A-711 sealed-tube neutron generator using the D-T reaction) thermal neutron source, electronic neutron imaging system, robotic positioner and manipulator for the source/imager, control trailer housing system control electronics and digital image processing system, mobile dark room for film processing, a self-contained electrical power source and a radiation safety system. For in situ aircraft inspection, the Robotic Scanner is programmed (in a teach-learn mode) to scan a region of the components (e.g., wings, stabilizers, etc.) using a control pendant. 38209 Beynon, T.D.; Constantine, G. Deep penetration radiography using 24.5 keY neutrons Nuclear Instruments and Methods in Physics Research, Vol. A264, No.2/3, pp. 526-527 (15 Feb. 1988) A series of experiments is described which demonstrates how neutrons from the natural iron filter on the Harwell PLUTO reactor can radiograph objects through 152 mm of mild steel. 38202 Catchen, G.L.; Hughes, D.E.; Kulkarni, A.K.; Ross, K.M.; Ammerman, W.R.
Development of a neutron-radiographic technique for investigating physical models of fluidized beds Chemical Engineering Communications, Vol. 54, No. 1-6, pp. 73-84 (1987)
243
Windsor, C.G.
The nature of the scattering process in small angle neutron scattering United Kingdom Atomic Energy Authority, Harwell, A E R E - M P D NBS-342, 16 pp. (May 1988) Neutron and X-ray small angle scattering provide, along with electron microscopy and diffraction, the principal tools for the microscopic characterisation of materials. Neutron, X-ray and electron beams have quite different properties. In fact, each has unique advantages. The penetration of neutrons through most materials is responsible for many of its applications. The ever increasing intensity of available X-ray beams is opening new fields. The advantage of electron beams is their ability to work in both real and reciprocal space. The problems of transforming the results of an experiment in reciprocal space to give an interpretation in real space are central to small angle scattering, and will be discussed in detail. Several examples will be given of the successful use of small angle neutron and X-ray scattering applied to problems where other techniques have failed to make a decisive contribution. 38812
Heidt, H.; Stade, J.
State and prospects of industrial neutron radiography in Germany (In
German) Materialprnfung, Vol. 30, No. 5, pp. 137-139 (May 1988) Although the first neutron radiographies in Germany were made nearly 50 years ago, this nondestructive testing method has not yet been widely used in industry. The main reason is the lack of mobile, intensive and low-cost neutron sources. Another important aspect is the availability of real-time inspection systems equipped with neutron image amplifiers which will accelerate the test and permit to represent dynamic processes. New applications for mobile neutron sources may be expected in aircraft inspection, in testing fibre-reinforced plastics, in different types of ceramic materials, in the building sector, in corrosion protection as well as with various problems encountered with lubrication agents.
38807 Pekarskii, G.Sh. Neutron backscattering nondestructive-test instruments Soviet Journal of Nondestructive Testing, Vol. 23, No. 7, pp. 512-515 (Mar. 1988) Calculations and measurements are used to make recommendations for neutron nondestructive testing and radioisotope automatic devices operating with one-sided access. Emphasis is placed on optimizing the major components for particular industrial purposes. Operating characteristics are given for various instruments: thickness gauges, level gauges, and means of detecting blocking points in pipe-lines, etc. 38625
McCauley, J. W.
NDT: Clearing the reliability bottleneck Ceramic Industry, Vol. 130, No. 3, pp. 33-34 (Mar. 1988) Nondestructive testing will play an important role in both the production of ceramic parts and flaw detection to improve their present low reliability, as they are more widely used in industry. A wide variety of nondestructive testing techniques, appropriate to different ceramic problems are listed, with ultrasonic, radiography, optical methods and neutron scattering being of most benefit for both green- state and sintered ceramics. 38526
Panakkal, J.P.; Ghosh, J.K.
A simple model for neutron radiography of uranium-plutonium mixed oxide fuel pins Journal of Nuclear Materials, Vol. 153, No. 1-3, pp. 82-85 (Apr. 1988) Neutron radiography has been used for monitoring plutonium enrichment in uranium-plutonium mixed oxide fuel pellets, inside welded nuclear fuel pins, by correlating the optical density of radiographs at the centre of the pellets and plutonium enrichment. Optical density data corresponding to different thicknesses of the pellets starting from the centre towards the periphery was generated by microdensitometer scanning of neutron radiographs of the experimental fuel pins. An attempt has been made to correlate the optical density at points corresponding to different thickness segments of the pellets and thermal neutron interaction probability (product of the total macroscopic neutron cross section and the distance traversed by the neutrons). Based on the experimental data generated, a simple model for transmission of neutrons through nuclear fuel pins has been evolved. Using this model, it is possible to predict the optical density of plutonium bearing fuel pins containing pellets of different composition or diameter in neutron radiographic investigations. 38517
Ratcliffe, B.J.
Investigation into the use of track-etch imaging to produce neutron radiographs from a non-reactor neutron source British Journal of Nondestructive Testing, Vol. 30, No. 3, pp. 183-188 (May 1988) A study is described of the use of cellulose nitrate with an enriched boron-10 converter screen for producing neutron radiographs from a RARDE non-reactor neutron assembly. Investigation into the required exposure and etching times has been made together with the measurement of unsharpnesses. The study shows that track-etching gives a sharper image than that obtained with
NDT International August 1989
the dysprosium transfer technique and the image is available for viewing in a much shorter time.
Lambrineas, P.; Finlayson, T.R.; Griffiths, J.R.; Howard, C.J.; Smith, T.F.
38220
Neutron diffraction residual stress measurements on a thin steel plate N D T International, Vol. 20, No. 5, pp. 285-290 (Oct. 1987) Residual stress measurements are made on a thermally stressed steel plate (4 mm thick) by using neutron diffraction. The sin/sup 2/psi technique, commonly employed to measure residual stresses by using X- ray diffraction, is applied to show that the stresses are biaxial, lying within the plane of the plate, and to evaluate the magnitude of the stresses. Measurements are made in both transmission and reflection geometries. Stress measurements made in a particular sample orientation are reproducible to within + - 10 MPa. The principal stresses determined from a series of such measurements have an uncertainty of + - 30 MPa, which is comparable to the + - 20 MPa commonly quoted for the X-ray sin/sup 2/psi technique. 38217 Brenizer, J.S.; Tobin, K.W.; Hylko, J.M.; McRae, D.D.; Jenkins, R.W. Jr. Quantitative measurement of equivalent water density in a burning
cigarette Materials Evaluation, Vol. 45, No. 11, pp. 1310-1314 (Nov. 1987) As a result of an ongoing attempt to quantify the deposition of hydrogenous compounds along the axial direction of a burning cigarette, software has been developed that takes into account the statistical nature of the neutron imaging system. This allows small variations in pixel luminance to be recorded in real time during the burn and correlated to an equivalent water density. The data collection process is based on spatial grouping of pixel locations within the rod as well as a time-averaged input of these discrete pixel groups. Once the system has been calibrated, a cigarette is positioned in the neutron beam. The area of interest is then divided into ten equal parts. All the pixel luminances in an area are averaged into one representative luminance value. As the cigarette burns, these areas are simultaneously sampled. A statistical analysis is performed for the real-time averages, and the data are stored in a file for later analysis. 38212
Ratcliffe, B.J.
Development of a non-reactor neutron radiographic assembly using a 12 MeV linear electron accelerator British Journal of Nondestructive Testing, Vol. 30, No. 2, pp. 94-98 (Mar. 1988) A description is given of the development of a neutron radiography assembly which does not use a nuclear reactor. The neutron radiographic technique developed can in some circumstances detect explosive in metal ordnance with a greater sensitivity than X- radiography. 38211
Mayers, J.; Baciocco, G.; Hannon, A.C.
Temperature measurement by neutron resonance radiography Rutherford Appleton Laboratory, Didcot (United Kingdom), RAL-88-017, 14 pp. (Mar. 1988) We present a new data analysis technique for obtaining temperatures from neutron resonance radiography measurements. The technique is applied to measurements on tantalum and rhenium foils, a high temperature engineering alloy and a model catalytic system. Temperatures have been obtained to an accuracy of better than + - 1 C in the temperature range 21 C to 600 C. The results, are in good agreement with theoretical simulations. 38210
Orphan, V.J.; Maung, T.
Robotic aircraft scanner for neutron radiographic inspection Proceedings of the 35th Conference on Remote Systems Technology, Los Angles, California (United States), Nov. 1987. pp. 195-199 American Nuclear Society, 1988. A robotic positioner and manipulator, a key component of a Mobile Neutron Radiography System (MNR) for aircraft inspection, is described. The MNRS is designed to inspect military aircraft for hidden corrosion in aluminum structures. MNRS is comprised of an accelerator-based (Kaman A-711 sealed-tube neutron generator using the D-T reaction) thermal neutron source, electronic neutron imaging system, robotic positioner and manipulator for the source/imager, control trailer housing system control electronics and digital image processing system, mobile dark room for film processing, a self-contained electrical power source and a radiation safety system. For in situ aircraft inspection, the Robotic Scanner is programmed (in a teach-learn mode) to scan a region of the components (e.g., wings, stabilizers, etc.) using a control pendant. 38209 Beynon, T.D.; Constantine, G. Deep penetration radiography using 24.5 keY neutrons Nuclear Instruments and Methods in Physics Research, Vol. A264, No.2/3, pp. 526-527 (15 Feb. 1988) A series of experiments is described which demonstrates how neutrons from the natural iron filter on the Harwell PLUTO reactor can radiograph objects through 152 mm of mild steel. 38202 Catchen, G.L.; Hughes, D.E.; Kulkarni, A.K.; Ross, K.M.; Ammerman, W.R.
Development of a neutron-radiographic technique for investigating physical models of fluidized beds Chemical Engineering Communications, Vol. 54, No. 1-6, pp. 73-84 (1987)
243