Some applications of ultrasonic image storage methods

LEVKOVSKII, Yu. L. Modeling of cavitation noise. Soviet Physics-Acoustics, Vol 13, No 3 (January-March 1968) pp 337-339 Eleven dimensional variables govern cavitation noise and were reduced to eight dimensionless parameters. To ensure approximate modeling of cavitation noise, it was assumed, through dimensional analysis, that the only condition was the observance of equal cavitation numbers (K (=2Apo/pv2) was the same in both model and nature, where Ap, was saturation vapour pressure, p was density, v was velocity at infinity). This analysis was limited to cases of small gas contents in bubbles, although pressure and power spectra were derived for the more general case. (5 References) (Ultrasonics 1968, abstract 802) LOBDELL, D. D. Particle size-amplitude relations for the ultrasonic atomizer. The Journal of the Acoustical Society of America, Vol 43, No 2 (February 1968) pp 229-231 Capillary wave amplitude is related to diameter of spherical particles ejected from ultrasonic atomizers-on the assumption that high amplitude wave crests may split into spherical drops and lower amplitude crests. (1) conservation of volume and (2) reduction or conservation of surface area are criteria. No quantitative results are given although predicted particle size (0.36h, where h is the wavelength of capillary waves) agrees with previous experimenters’ results and is verified qualitatively. (8 References, 1 Figure) (Ultrasonics 1968, abstract 803) LOVELACE, J. F., LUINI, L.A. A correlation study between ultrasonic, radiographic and visual examination of heavy steel plate weldments. Materials Evaluation, Vol 26, No 1 (January 1968) pp l-7 16 HY-80 steel plate butt welds were inspected ultrasonically (both manual and automatic), radiographically and visually: manual ultrasonic tests agreed with visual in 69% of 95 cases; automatic ultrasonic tests agreed with visual in 637~ while radiographic tests agreed with visual in only 36% of cases. Radiography was performed and interpreted according to NavShips 250-63’7-2. Manual ultrasonic tests were done by both Krautkramer USIP-10 and Branson Sonoray Model 50: for all 15/8, 2 and 3in test welds, the probe was s/4 x 3/4in, 2.25MHz Krautkramer angle beam probe with a 45” beam in the steel plate; lin plates were tested by a r/,in diameter Branson probe of the same frequency and angle. Automatic ultrasonic tests were conducted by equipment designed by Lovelace and Luini. The greatest discrepancy between ultrasonic and radiographic method was for cracks and porosity: cracks were detected most reliably by ultrasound and vice versa for small isolated porosity. In addition, ultrasonic tests could determine defect depth and could be adapted to particular welding processes. (9 References, 8 Figures) (Ultrasonics 1968, abstract 804) LYNNWORTH, L. C. Ultrasonics probes using shear wave crystaB+principles. Materials Evaluation. Vol 25. No 12 (December 1967) pp 265-277 This paper has a triple purpose: (1) to explain how longitudinal, shear, Rayleigh, Lamb and Love waves may be generated and detected with shear wave crystals; (2) to show that such waves can be coupled by pressure, optical contact (both at all angles of incidence) and fluid (at oblique incidence), besides bonding; (3) to spotlight the inherent advantages of shearwave crystals in ultrasonic testing. Pressure coupling was achieved with pressures in the range lOOO10, OOOpsi. Optical coupling was obtained with polished surface finishes optically flat to lnin. Shear waves have been applied to thermometry, flaw detection and thickness gaging of steels around lOOO-1400°C. Under (1). mode converting acrylic wedges have limitations as tools’of ndt: upper frequency limit-6MHz; distortion temperature-100°C; appearance of higher order modes; only SV-type waves can be launched. These and similar limitations of Rayleigh, Lamb and Love waves are overcome partly by launching from shear wave crystals: in this way, the range of ultrasonic testing should be extended from l-1OMHz to 0. l-100MHz. (43 References, 9 Figures, 2 Tables) (Ultrasonics 1968, abstract 805)

MICHALSKI, F. Some applications of ultrasonic image storage methods. Materialprufung, Vol 10, No 2 (February 1968) pp 37-42 (In German) More and more importance is being attached not only to the traditional method of ultrasonic testing, that is, manual scanning and visual observation of the screen, but also to the automation of the procedure and the storage of results. A special form of registration is the image storage method. Thereby 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. (5 References, 10 Figures) (Ultrasonics 1968, abstract 806)

MITSKEVICH, A.M. Motion of a body over a tangentially vibrating surface taking account of friction. Soviet Physics-Acoustics, Vol 13, No 3 (January-March 1968) pp 348-351 The motion of mass, mi, was predicted when impulse, mixu, was imparted to it over frictional surface vibrating with frequency, f, and amplitude, t,,: frictional force in presence of vibration decreased by factor l/n, where n = xzf[,/xo(x, (< 2nfto), in comparison with frictional force in absence of vibration. Two experiments agreed with theoretical results: (1) longitudinal vibrations (2OkHz) were excited in bar and variations in velocity of particles (1 x lmm) were recorded photographically (frame speed = 64/s) (2) in metal cutting, friction was deduced by factor of three and decreased in proportion to increase in amplitude of vibrations at fixed frequency (see above equation). (2 References, 4 Figures) (Ultrasonics 1968, abstract 807)

McCOWIN, M. L., BEYER, N. S. Ultrasonic non-bond inspection of tubular fuel elements. Materials Evaluation, Vol 26, No 2 (February 1968) pp 17-20 Non-bonding and other defects in tubular fuel elements were detected and recorded by pulse-echo reflection of ultrasound at 15MHz. Fuel elements (diameters 2-4in and lengths 27i/, and 3lQn (lin N 2.5cm)) were inspected for non-bonds i/iein diameter. Reflections at the water interfaces with outside and inside diameters were resolved by a transducer with focal length - lIzin and focal spot N $ein diameter. Wall thicknesses as small as 0.05in were inspected using synchronous monitoring device (delay time 0.25~~) to distinguish the above reflections. A bibliography of six books is also given. (2 References, 9 Figures) (Ultrasonics 1968, abstract 808)

PIRS, J. Investigations into utilization of ultrasonic attenuation measurements for distinction of various microstructures of steel 42 CrMo4. Materialprufung, Vol 10, No 2 (February 1968) pp 43-49 (In German) Ultrasonic attenuation measurements were carried out in the range 3-50MHZ on specimens of pearlitic-plus-ferritic, bainitic and martensitic structure. Investigations tried to find, by means of electron microscopy, to what extent different grain sizes and grain size distribution influence ultrasonic scattering and different structures are responsible for attenuation. In the frequency range investigated, the ultrasonic attenuation coefficients were highest in pearliteplus-ferrite, intermediate in bainite and lowest in martensite. (21 References, 6 Figures, 1 Table) (Ultrasonics 1968, abstract 809) ULTRASONICS July 1968

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