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Ultrasonic phase velocity by the pulse-echo-overlap method incorporating diffraction phase corrections
MAYER, W. G., IAMERS, G. B. and AUTH,D. C. Interaction of llglxt and ultrasonic surface waves. Journal of the Acoustical Society of America, Vol 42, No 6 (December 1967) ~1255 The intensity distribution is calculated for the orders of a light diffraction pattern produced by the interaction of a progressive ultrasonic surface wave and a monochromatic light beam. The amplitude of the surface wave is determined from the light intensity distribution in the diffraction pattern. The spacing of the diffraction orders is related to the surface wave velocity and the angle of light incidence. (Ultrasonics 1968, abstract 769)
MICHALSKI, F Some applicat.ions of ultrasonic image storage methods. Materialpriifung, Vol 10, No 2 (February 1968) pp37 -42 Increasing importance is being attached not only to the traditional method of ultrasonic testing, i.e. manual scanning and visual observation of the screen, but also to the automation of the procedure and the storage of the results. A special form of registration is the image storage method with which the total impression of a test can be retained by means of a photographic or electronic method. In this way a document is obtained which is at the same time more concrete and more definite in its evidence. (Ultrasonics 1968, abstract 770)
NOZDREV, V. F. and STEPANOV, N. G. On the intersection of uItrasonic velocity curves in liquids SIldillSStlUdSd
VapaursnearthecrtticSlpoint.
Akusticheskii Zhurnal, Vol 13, No 4 (October-December 1967) ~~631-633 This paper reports measurements of the velocity of ultrasonic waves (3-4MHz) in methyltrichlorosilane, dimethyldichlorosilane, trimethylchlorosilane and ethyltrichlorosilane. An optical diffraction method was used. It was found that the velocity of sound in saturated methyltrichlorosilane and ethyltrichlorosilane vapour is less than in their liquid phases at all temperatures. The Schneider effect was found in the two other substances at temperatures above 0.997 Tcrit and 0.996 Tcrit (dimethyldichlorosilane and trimethylchlorosilane respectively). The effect is real in so far as it lies outside the range of experimental error. (Ultrasonics 1968, abstract 771)
OLAF, J. Experimenta on the effects of high-intensity ultrasonic radiation on coal. Gliickauf-forschungshefte, Vol 28, No 5 (October 1967) ~~247-250 The object of these studies, carried out for the European Community for Coal and Steel, was to determine how ultrasonic radiation could be used to advantage in the various processes employed in the coal industry. The investigations included the application of ultrasonic irradiation to the extraction of coal particles from organic and inorganic solvents, the coagulation of slurries, the disintegration of finely powdered coal, the consolidation of pressings, the dehydration of filter muds and the removal of tar mists from raw gas. Generally speaking, significant advantages were obtained in only two of these applications. These were (1) in the extraction of coal from ultrasonically irradiated suspensions in organic solvents, where substantial improvements in the yield (shown in a table) were achieved as compared with non-irradiated samples, and (2) in the manufacture of billets by the compression of coal particles, where the relative density of the final product could be raised by about lo-12%) at a given forming pressure, when the material was subjected to ultrasonic irradiation during the compression operation. A graph shows how billets with a relative density of up to 1. lg/cm3 could be obtained at a static forming pressure of only 6. 32kg/cm2. (Ultrasonics 1968, abstract 772)
PAPADAEIS, E. P. Ultrasonic phase velocity by the p&e-echo-overlap method incorporatingdiffraction pkuie correction13. Journal of the Acoustical Society of America, Vol 42, No 5 (November 1967) ~1045 The pulse-echo-overlap method for ultrasonic time-delay measurements is reviewed. In this method, pairs of echoes are compared by driving the x-axis of a viewing oscilloscope at a frequency equal to the reciprocal of the travel time between the echoes. A method for choosing the correct cyclic overlap for the rf within the echoes is given. Use of the proper cyclic overlap permits accurate measurement of ultrasonic phase velodity. When corrections for the phase advance due to ultrasonic diffraction are applied to the travel times between various pairs of echoes, the accuracy of the average round-trip travel time is improved. Experimental verification of this is presented for longitudinal waves in isotropic materials and in the pure mode directions in cubic crystals. Delay times are accurate to 0.2nsec or better. (Ultrasonics 1968,abstract 773)
PIRS, J. Investigations into utilization of ultrazonlc attenuation measurementsi for distiaction of various micnwtruduree of steel 42CrMo4. Materialprtif’ung, Vol 10, No 4 (February 1968) pp43-49 Ultrasonic attenuation measurements were carried out in the range 3-50MHz on specimens of pearlitic-plus-ferritic, bainitic and martensitic structure. Attempts have been made to find out, also by means of electron microscopy, to what extent different grain sizes and grain-size distributions influence ultrasonic scattering, and different structures are responsible for attenuation. In the frequency range investigated the ultrasonic attenuation coefficients were highest in pearlite-plus-ferrite, intermediate in bainite and lowest in martensite. (Ultrasonic 1968, abstract 774)
PITTAWAY, R. G. UItrasonic testing of resistance spot welds. Welding and Metal Fabrication,Vol 35,No 11 (November 1967) pp443-447 This article describes a recently developed technique for the non-destructive testing of resistance spot welds in sheet metal assemblies. The method uses an ultrasonic pulse-echo technique and works on the principle of measuring differences in ultrasonic attenuation between welds of varying quality. The practical application of this technique and its correlation with destructive testing methods are also discussed. (Ultrasonics 1968, abstract 775)
RILEY, W. A. and KLEIN, W. R. Plezo-optic coefficients of liquids. Journal of the Acoustical Society of America, Vol 42, No 6 (December 1967) ~1258 A pulsed ultrasonic light diffraction technique was used to obtain values of the piezo-optic coefficient for twenty four liquids. From these results, several empirical expressions were obtained that facilitate calculation of this parameter. (Ultrasonics 1968, abstract 776)
SCRASE, T. Self-guided ultrasonic probe scans contours. Metalworking Production, (17th January 1968) ~~45-46 The development of a simple contour-following device carrying an ultrasonic probe makes it possible to examine minutely every part of the main engine shafts of the Olympus 593 used for the Concorde in less than one hour. The article describes the testing equipment which can save thousands of pounds in wasted machining operations (Ultrasonics 1968, abstract 777) ULTRASONICS April 1968
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MICHALSKI, F Some applicat.ions of ultrasonic image storage methods. Materialpriifung, Vol 10, No 2 (February 1968) pp37 -42 Increasing importance is being attached not only to the traditional method of ultrasonic testing, i.e. manual scanning and visual observation of the screen, but also to the automation of the procedure and the storage of the results. A special form of registration is the image storage method with which the total impression of a test can be retained by means of a photographic or electronic method. In this way a document is obtained which is at the same time more concrete and more definite in its evidence. (Ultrasonics 1968, abstract 770)
NOZDREV, V. F. and STEPANOV, N. G. On the intersection of uItrasonic velocity curves in liquids SIldillSStlUdSd
VapaursnearthecrtticSlpoint.
Akusticheskii Zhurnal, Vol 13, No 4 (October-December 1967) ~~631-633 This paper reports measurements of the velocity of ultrasonic waves (3-4MHz) in methyltrichlorosilane, dimethyldichlorosilane, trimethylchlorosilane and ethyltrichlorosilane. An optical diffraction method was used. It was found that the velocity of sound in saturated methyltrichlorosilane and ethyltrichlorosilane vapour is less than in their liquid phases at all temperatures. The Schneider effect was found in the two other substances at temperatures above 0.997 Tcrit and 0.996 Tcrit (dimethyldichlorosilane and trimethylchlorosilane respectively). The effect is real in so far as it lies outside the range of experimental error. (Ultrasonics 1968, abstract 771)
OLAF, J. Experimenta on the effects of high-intensity ultrasonic radiation on coal. Gliickauf-forschungshefte, Vol 28, No 5 (October 1967) ~~247-250 The object of these studies, carried out for the European Community for Coal and Steel, was to determine how ultrasonic radiation could be used to advantage in the various processes employed in the coal industry. The investigations included the application of ultrasonic irradiation to the extraction of coal particles from organic and inorganic solvents, the coagulation of slurries, the disintegration of finely powdered coal, the consolidation of pressings, the dehydration of filter muds and the removal of tar mists from raw gas. Generally speaking, significant advantages were obtained in only two of these applications. These were (1) in the extraction of coal from ultrasonically irradiated suspensions in organic solvents, where substantial improvements in the yield (shown in a table) were achieved as compared with non-irradiated samples, and (2) in the manufacture of billets by the compression of coal particles, where the relative density of the final product could be raised by about lo-12%) at a given forming pressure, when the material was subjected to ultrasonic irradiation during the compression operation. A graph shows how billets with a relative density of up to 1. lg/cm3 could be obtained at a static forming pressure of only 6. 32kg/cm2. (Ultrasonics 1968, abstract 772)
PAPADAEIS, E. P. Ultrasonic phase velocity by the p&e-echo-overlap method incorporatingdiffraction pkuie correction13. Journal of the Acoustical Society of America, Vol 42, No 5 (November 1967) ~1045 The pulse-echo-overlap method for ultrasonic time-delay measurements is reviewed. In this method, pairs of echoes are compared by driving the x-axis of a viewing oscilloscope at a frequency equal to the reciprocal of the travel time between the echoes. A method for choosing the correct cyclic overlap for the rf within the echoes is given. Use of the proper cyclic overlap permits accurate measurement of ultrasonic phase velodity. When corrections for the phase advance due to ultrasonic diffraction are applied to the travel times between various pairs of echoes, the accuracy of the average round-trip travel time is improved. Experimental verification of this is presented for longitudinal waves in isotropic materials and in the pure mode directions in cubic crystals. Delay times are accurate to 0.2nsec or better. (Ultrasonics 1968,abstract 773)
PIRS, J. Investigations into utilization of ultrazonlc attenuation measurementsi for distiaction of various micnwtruduree of steel 42CrMo4. Materialprtif’ung, Vol 10, No 4 (February 1968) pp43-49 Ultrasonic attenuation measurements were carried out in the range 3-50MHz on specimens of pearlitic-plus-ferritic, bainitic and martensitic structure. Attempts have been made to find out, also by means of electron microscopy, to what extent different grain sizes and grain-size distributions influence ultrasonic scattering, and different structures are responsible for attenuation. In the frequency range investigated the ultrasonic attenuation coefficients were highest in pearlite-plus-ferrite, intermediate in bainite and lowest in martensite. (Ultrasonic 1968, abstract 774)
PITTAWAY, R. G. UItrasonic testing of resistance spot welds. Welding and Metal Fabrication,Vol 35,No 11 (November 1967) pp443-447 This article describes a recently developed technique for the non-destructive testing of resistance spot welds in sheet metal assemblies. The method uses an ultrasonic pulse-echo technique and works on the principle of measuring differences in ultrasonic attenuation between welds of varying quality. The practical application of this technique and its correlation with destructive testing methods are also discussed. (Ultrasonics 1968, abstract 775)
RILEY, W. A. and KLEIN, W. R. Plezo-optic coefficients of liquids. Journal of the Acoustical Society of America, Vol 42, No 6 (December 1967) ~1258 A pulsed ultrasonic light diffraction technique was used to obtain values of the piezo-optic coefficient for twenty four liquids. From these results, several empirical expressions were obtained that facilitate calculation of this parameter. (Ultrasonics 1968, abstract 776)
SCRASE, T. Self-guided ultrasonic probe scans contours. Metalworking Production, (17th January 1968) ~~45-46 The development of a simple contour-following device carrying an ultrasonic probe makes it possible to examine minutely every part of the main engine shafts of the Olympus 593 used for the Concorde in less than one hour. The article describes the testing equipment which can save thousands of pounds in wasted machining operations (Ultrasonics 1968, abstract 777) ULTRASONICS April 1968
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