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40336 Neutron beam tomography software
- N D T abstracts N D T Abstracts is a current awareness service compiled by the National N D T Centre, Harwell Laboratory, Didcot, Oxon, O X l l 0RA, UK. The entries are drawn from over 500 British and International publications. Each issue concentrates on one or two subject areas, and contains abstracts entered from 1987 to the present. The subjects covered in previous issues are: Acoustic emission (cracks and defects) - April 1989; E d d y current techniques - June 1989; Magnetic testing techniques - February 1989; Real-time radiography - April 1989
Neutron radiography 40336
Newbery, A. C.R.
Neutron beam tomography software H a h n - M e i t n e r - I n s t i t u t , B e r l i n ( W e s t G e r m a n y ) H M I - B 450, 44 pp. ( M a y 1988) When a sample is traversed by a neutron beam, inhomogeneities in the sample will cause deflections, and the deflections will permit conclusions to be drawn concerning the location and size of the inhomogeneities. The associated computation is similar to problems in tomography, analogous to X ray tomography though significantly different in detail. Point-sample information is not available but mean values over short line segments are. Since each mean value is derived from a separate neutron counter, the quantity of available data has to be modest; also, since each datum is an integral, its geometric precision is inferior to that of X ray data. The software is designed to cope with these difficulties.
40139 Reno, R.C.; Fields, R.J.; Clark, A.V. Jr. Crystallographic texture in rolledaluminum plates:neutron pole figure measurements Review of P r o g r e s s in Q u a n t i t a t i v e N o n d e s t r u c t i v e
Evaluation, W i l l i a m s b u r g , V i r g i n i a ( U n i t e d States), 22-26 Jun. 1987. Vol. 7B, pp. 1439-1446. E d i t e d b y D . D . T h o m p s o n a n d D . E . C h i m e n t i , P l e n u m Press, 1988. In crystalline materials with anisotropic elastic constants, the propagation of ultrasound is strongly dependent upon crystallographic texture. Ultrasound propagation is also affected by impurities, grain boundaries, and other inhomogeneities, and so it is desirable that ultrasound texture measurements can be compared with more direct crystallographic measurements. Neutron diffraction is an excellent method for studying texture in bulk samples directly. Neutrons penetrate deeply into materials. The extremely high penetration in aluminum permits generation of complete pole figure without having to switch from reflection to transmission modes. Analysis of the pole figure results in orientation distribution function coefficients (ODC's) can be compared to those measured with ultrasound.
Kupperman, D.S.; Majumdar, S.; MacEwen, S.R.; Hitterman, R.L.; Singh, J.P.; Roberts, R.A.; Routbort, J.L. 39988
Nondestructive characterization of ceramic composite whiskers with neutron diffraction and ultrasonic techniques R e v i e w of Progress in Q u a n t i t a t i v e N o n d e s t r u c t i v e E v a l u a t i o n , W i l l i a m s b u r g , V i r g i n i a ( U n i t e d States), 22-26 Jun. 1987. Vol. 7B, pp. 961-970. E d i t e d b y D . D . T h o m p s o n a n d D . E . C h i m e n t i , P l e n u m Press, 1988. In this paper some results are presented of a program at Argonne National Laboratory (ANL) in which the characterization and control of interfacial bonds in composites are being investigated. The General Purpose Powder Diffractometer (GPPD) at the Intense Pulsed Neutron Source (IPNS) at ANL has been employed to measure residual strains in a ceramic-ceramic composite by neutron diffraction techniques. From the residual strain measurements it is possible to calculate stresses at the fiber-matrix interface. The results of the residual strain experiment and the initial results from experiments in which ultrasonic techniques were used to assess whisker-matrix bonding are discussed in this paper.
Anisimov, Yu.S.; Chernenko, S.P.; lvanov, A.B.; Netusil, T.; Peshekhonov, V.D.; Smykov, L.P.; Zanevsky, Yu. V.; Cisar, M.; Horacek, J.; Knourek, J.; Moucka, L.; Nezmar, L.; Pellar, L.; Pochman, J.; Schneider, Z.; Sidak, Z.; Vrba, I.; Bizek, V.; Zavadil, Z.; Beran, P.; Cerny, K. 39925
Development and investigation of a neutron radiography i m a g i n g system with a low-pressure multistep chamber N u c l e a r I n s t r u m e n t s a n d M e t h o d s in Physics R e s e a r c h , Vol. A273, No. 2- 3, pp. 731-734 (1988) An imaging system of thermal neutrons for an investigation of digital neutron
240
radiography has been developed and tested. Some characteristics obtained on a neutron radiography beam of an experimental reactor are reported. The coordinates of each event are determined in this system. After processing with a computer, a radiograph, accumulated in a histogramming memory of 64 K 16-bit words, is presented on a colour display. A 230 x 180 ram/sup 2/low-pressure multistep chamber is used as a detector. Neutron conversion takes place in a 6 micron boron layer enriched to 86% in sup/10/B. The detection efficiency of thermal neutrons is no less than 3%. The count rate of the system reaches up to 2 x 10 sup/5/events per second. A radiograph can be obtained within 10 minutes. The sensitivity of this system to gamma-background is low. One event/s is detected for a background of 1 R/h. The spatial resolution is found to be 0.7 mm using a cadmium knife edge. The integral nonlinearity is less than 0.4%. The possibility of using a hydrogeneous converter in this system for neutron radiography is discussed. 39923
Lorentzen, T.
Nondestructive evaluation of residual stresses by neutron diffraction N D T I n t e r n a t i o n a l , Vol. 21, No. 6, pp. 385-388 (Dec. 1988) A technique for the nondestructive determination of residual stresses using neutron diffraction is described. The basic principles are explained, and two experimental set-ups for the determination of type 1 and type 2 stresses are presented. Problems concerning texture and anisotropic effects are discussed and the potential of the technique is illustrated by examples related to nondestructive evaluation (NDE) of structural components. 39755
Ikeda, Y.; Sakai, H.; Ohkubo, K.; Matsumoto, G.
Neutron computed tomography w i t h a h i g h - s p e e d i m a g e processor M a t e r i a l s E v a l u a t i o n , Vol. 46, No. 11, pp. 1471-1476 (Oct. 1988) Neutron computed tomography (NCT) using real-time neutron radiography and an electronic image-processing technique is described in this paper. A high-speed image processor, TOSPIX-II, was used for image inputting and reconstruction. Including pre-and post-image processing, 1.0 mm resolution of CT images was obtained with 50 to 100 projection data, and the required computing time for reconstruction was about 20 min. It was recognized that by further improvement of the neutron television system and use of some higher-grade central processing unit (CPU), the resolution will be greatly improved and the requirement for CPU time will be reduced. 39753
Domanus, J. C.
International neutron radiography newsletter No. 17 - N R W G test program: Parts 2, 3 and 4 British J o u r n a l o f N o n d e s t r u c t i v e Testing, Vol. 31, No. 1, pp. 35-38 (Jan. 1989) In Part 1 the scope of the NRWG Test Program was given and test items, exposure and recording techniques as well as measurements were described. Results of those measurements were described in Parts 2 and 3 of the final report whereas Part 4 gives the conclusions from the whole Test program. 39695
Marsters, G.F.
Corrosion and your a i r c r a f t C a n a d i a n Society for N o n d e s t r u c t i v e Testing J o u r n a l , Vol. 9, No. 5, pp. 36-37, 39-41 ( S e p . - O c t . 1988) This paper addresses the topic of corrosion and related safety in aircraft. Information is presented to enable pilots to check their vehicles. The integrity of the craft's metal frame can be discussed under four main categories, fatigue, overstress, tire and corrosion. This last is discussed in some detail and areas liable to corrosion are suggested. Appropriate use of various NDE techniques is discussed and some case histories are given. 39686
Mix, P.E.
Introduction to nondestructive testing - A training guide J o h n W i l e y a n d Sons, 420 pp. (1987). I S B N 0-471-83126-3 This text book of nondestructive testing covers all the major techniques in detail sufficient to qualify the student for examinations levels I, II and IIl of the American Society for Nondestructive Testing.
NDT International August 1989
Neutron radiography 40336
Newbery, A. C.R.
Neutron beam tomography software H a h n - M e i t n e r - I n s t i t u t , B e r l i n ( W e s t G e r m a n y ) H M I - B 450, 44 pp. ( M a y 1988) When a sample is traversed by a neutron beam, inhomogeneities in the sample will cause deflections, and the deflections will permit conclusions to be drawn concerning the location and size of the inhomogeneities. The associated computation is similar to problems in tomography, analogous to X ray tomography though significantly different in detail. Point-sample information is not available but mean values over short line segments are. Since each mean value is derived from a separate neutron counter, the quantity of available data has to be modest; also, since each datum is an integral, its geometric precision is inferior to that of X ray data. The software is designed to cope with these difficulties.
40139 Reno, R.C.; Fields, R.J.; Clark, A.V. Jr. Crystallographic texture in rolledaluminum plates:neutron pole figure measurements Review of P r o g r e s s in Q u a n t i t a t i v e N o n d e s t r u c t i v e
Evaluation, W i l l i a m s b u r g , V i r g i n i a ( U n i t e d States), 22-26 Jun. 1987. Vol. 7B, pp. 1439-1446. E d i t e d b y D . D . T h o m p s o n a n d D . E . C h i m e n t i , P l e n u m Press, 1988. In crystalline materials with anisotropic elastic constants, the propagation of ultrasound is strongly dependent upon crystallographic texture. Ultrasound propagation is also affected by impurities, grain boundaries, and other inhomogeneities, and so it is desirable that ultrasound texture measurements can be compared with more direct crystallographic measurements. Neutron diffraction is an excellent method for studying texture in bulk samples directly. Neutrons penetrate deeply into materials. The extremely high penetration in aluminum permits generation of complete pole figure without having to switch from reflection to transmission modes. Analysis of the pole figure results in orientation distribution function coefficients (ODC's) can be compared to those measured with ultrasound.
Kupperman, D.S.; Majumdar, S.; MacEwen, S.R.; Hitterman, R.L.; Singh, J.P.; Roberts, R.A.; Routbort, J.L. 39988
Nondestructive characterization of ceramic composite whiskers with neutron diffraction and ultrasonic techniques R e v i e w of Progress in Q u a n t i t a t i v e N o n d e s t r u c t i v e E v a l u a t i o n , W i l l i a m s b u r g , V i r g i n i a ( U n i t e d States), 22-26 Jun. 1987. Vol. 7B, pp. 961-970. E d i t e d b y D . D . T h o m p s o n a n d D . E . C h i m e n t i , P l e n u m Press, 1988. In this paper some results are presented of a program at Argonne National Laboratory (ANL) in which the characterization and control of interfacial bonds in composites are being investigated. The General Purpose Powder Diffractometer (GPPD) at the Intense Pulsed Neutron Source (IPNS) at ANL has been employed to measure residual strains in a ceramic-ceramic composite by neutron diffraction techniques. From the residual strain measurements it is possible to calculate stresses at the fiber-matrix interface. The results of the residual strain experiment and the initial results from experiments in which ultrasonic techniques were used to assess whisker-matrix bonding are discussed in this paper.
Anisimov, Yu.S.; Chernenko, S.P.; lvanov, A.B.; Netusil, T.; Peshekhonov, V.D.; Smykov, L.P.; Zanevsky, Yu. V.; Cisar, M.; Horacek, J.; Knourek, J.; Moucka, L.; Nezmar, L.; Pellar, L.; Pochman, J.; Schneider, Z.; Sidak, Z.; Vrba, I.; Bizek, V.; Zavadil, Z.; Beran, P.; Cerny, K. 39925
Development and investigation of a neutron radiography i m a g i n g system with a low-pressure multistep chamber N u c l e a r I n s t r u m e n t s a n d M e t h o d s in Physics R e s e a r c h , Vol. A273, No. 2- 3, pp. 731-734 (1988) An imaging system of thermal neutrons for an investigation of digital neutron
240
radiography has been developed and tested. Some characteristics obtained on a neutron radiography beam of an experimental reactor are reported. The coordinates of each event are determined in this system. After processing with a computer, a radiograph, accumulated in a histogramming memory of 64 K 16-bit words, is presented on a colour display. A 230 x 180 ram/sup 2/low-pressure multistep chamber is used as a detector. Neutron conversion takes place in a 6 micron boron layer enriched to 86% in sup/10/B. The detection efficiency of thermal neutrons is no less than 3%. The count rate of the system reaches up to 2 x 10 sup/5/events per second. A radiograph can be obtained within 10 minutes. The sensitivity of this system to gamma-background is low. One event/s is detected for a background of 1 R/h. The spatial resolution is found to be 0.7 mm using a cadmium knife edge. The integral nonlinearity is less than 0.4%. The possibility of using a hydrogeneous converter in this system for neutron radiography is discussed. 39923
Lorentzen, T.
Nondestructive evaluation of residual stresses by neutron diffraction N D T I n t e r n a t i o n a l , Vol. 21, No. 6, pp. 385-388 (Dec. 1988) A technique for the nondestructive determination of residual stresses using neutron diffraction is described. The basic principles are explained, and two experimental set-ups for the determination of type 1 and type 2 stresses are presented. Problems concerning texture and anisotropic effects are discussed and the potential of the technique is illustrated by examples related to nondestructive evaluation (NDE) of structural components. 39755
Ikeda, Y.; Sakai, H.; Ohkubo, K.; Matsumoto, G.
Neutron computed tomography w i t h a h i g h - s p e e d i m a g e processor M a t e r i a l s E v a l u a t i o n , Vol. 46, No. 11, pp. 1471-1476 (Oct. 1988) Neutron computed tomography (NCT) using real-time neutron radiography and an electronic image-processing technique is described in this paper. A high-speed image processor, TOSPIX-II, was used for image inputting and reconstruction. Including pre-and post-image processing, 1.0 mm resolution of CT images was obtained with 50 to 100 projection data, and the required computing time for reconstruction was about 20 min. It was recognized that by further improvement of the neutron television system and use of some higher-grade central processing unit (CPU), the resolution will be greatly improved and the requirement for CPU time will be reduced. 39753
Domanus, J. C.
International neutron radiography newsletter No. 17 - N R W G test program: Parts 2, 3 and 4 British J o u r n a l o f N o n d e s t r u c t i v e Testing, Vol. 31, No. 1, pp. 35-38 (Jan. 1989) In Part 1 the scope of the NRWG Test Program was given and test items, exposure and recording techniques as well as measurements were described. Results of those measurements were described in Parts 2 and 3 of the final report whereas Part 4 gives the conclusions from the whole Test program. 39695
Marsters, G.F.
Corrosion and your a i r c r a f t C a n a d i a n Society for N o n d e s t r u c t i v e Testing J o u r n a l , Vol. 9, No. 5, pp. 36-37, 39-41 ( S e p . - O c t . 1988) This paper addresses the topic of corrosion and related safety in aircraft. Information is presented to enable pilots to check their vehicles. The integrity of the craft's metal frame can be discussed under four main categories, fatigue, overstress, tire and corrosion. This last is discussed in some detail and areas liable to corrosion are suggested. Appropriate use of various NDE techniques is discussed and some case histories are given. 39686
Mix, P.E.
Introduction to nondestructive testing - A training guide J o h n W i l e y a n d Sons, 420 pp. (1987). I S B N 0-471-83126-3 This text book of nondestructive testing covers all the major techniques in detail sufficient to qualify the student for examinations levels I, II and IIl of the American Society for Nondestructive Testing.
NDT International August 1989