| NDTnet
ISSN: 1435-4934 The e-Journal of Nondestructive Testing & Ultrasonics - Publisher
The Journal's focus is on Nondestructive Testing (NDT) and Ultrasonic Testing (UT) in particular | Departments
Exhibition Virtual Library UT by A-Z UTonline Forum ! NDT NewsWeb Abstracts Publications Events Editorial | |||||
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| This Month's Introduction |
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EMATs domain includes hot applications, dry coupling and tasks for polarized shear waves. In recent years important developments have been made in the the filed of transducer array technology.
This month's topics are well supported by our UTonline Forum. |
| NDT TOPIC |  This Month's Articles ----- | |||||
| UT EMAT Array |
Generation of Horizontally Polarized Shear Waves with EMAT Transducers
[A] Elektromagnetische Ultraschall (EMUS-) Wandler zur Erzeugung horizontal polarisierter Transversalwellen Longitudinal waves and vertically polarized Shear waves (Sv - Waves) have been used for some time now in ultrasonic testing. These two kinds of spherical waves can be generated by using a coupling medium between the piezoelectric transducer and the work piece. The third kind of spherical wave - horizontally polarized Shear waves (SH - Waves) - are not often applied in ultrasonic testing because until recently only conventional transducers, which require very viscous couplants, were used, making transducer manipulation virtually impossible. Now electromagnetic ultrasonic transducers (EMAT) have been developed. These can generate and receive SH - Waves. They don't need a couplant for transmitting waves in metals, just close contact with the surface. The following chapter briefly describes the different methods of generating electromagnetic SH - Waves, EMAT transducers and some of their characteristics. G. Hübschen, FhG IzfP Saarbruecken | 
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| UT EMAT |
An Evaluation of EMAT Technology for High-Temperature NDE
[A] Materials Technology Institute (MTI) funded Southwest Research Institute (SwRI) to perform an unbiased evaluation of the present state of the art on EMAT technology for high-temperature NDE of remaining wall thickness. The project goal was to provide a standard set of test specimens, containing representative corrosion-like defects and remaining wall thicknesses, and have several EMAT vendors inspect them under controlled conditions so that a benchmark could be made on the state of the art. To accomplish this goal, SwRI (1) developed a test protocol, (2) designed and fabricated test specimens for use during EMAT evaluations, (3) designed and fabricated a high temperature test fixture, (4) conducted laboratory evaluations, and (5) assimilated the results. The work associated with each of these areas is described in this article. Glenn M. Light (SwRI), Joseph Demo (MTI) | 
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| UT EMAT | New EMAT Probes useful for various Applications [A] Neue vielfältig einsetzbare EMUS-Wandler A new fabrication concept of EMAT-SH and SV Probes for a frequency range of 1 MHz to 2.5 MHz has been developed. Models of arrays with up to 6 transmitter and 6 receiver elements in a housing of 40 mm x 40 mm x 30 mm are available. Probe modifications for curved geometries of a radius as low as to 5.4 mm are possible. Examples of wall thickness measurement and flaw detection are discussed. D.Lingenberg, R.Meier, Siemens KWU Erlangen | |||||
| UT EMAT 
| Back in Style: Magnetostrictive Sensors Mindful of the past, SwRI scientists find fitting solutions to some of today's high-tech problems by Dr. Hegeon Kwun, SwRI Homepage | |||||
| UT Array | New Incoming Forum Article (16.3.98) Customised Design of Transducers for Non-destructive Testing [A]=Abstract The current performance requirements of non-destructive testing vary greatly. Even though standard transducers obtain satisfactory results for certain applications, the evolution of the industry manager justifies more and more seeking out transducers designed to order. The issue is notably, to define at the earliest, and most accurately, the specific character of a set of objectives and constraints. The example presented by this article relates to the design of an array transducer. Rémi Berriet*, Steve Mahaut**; *IMASONIC, **CEA/CEREM | 
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| UT Array |
Ultrasonic Inspection of Copper Canisters using Phase Arrays [A] The objective of this project is to develop a fully automated ultrasonic technique for assessing the integrity of the circumferential weld between the lid and wall of copper lined canisters for nuclear waste fuel. The aim of this research was to evaluate performance of linear ultrasonic arrays used for the inspection of the electron beam (EB) weld in copper canisters. The experimental part includes inspection of various canister samples using the ultrasonic array system ALLIN from NDT Systems and the linear ultrasonic array from Imasonic. by T. Stepinski, P. Wu, E. Martinez, Uppsala University | 
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| UT Array |
Real time, large area ultrasound imaging system using two-dimensional array technique
[A] A novel NDE system with an ultrasound sensitive multi-element array has been demonstrated and is currently in product development. The tool is capable of imaging internal defects (e.g. voids, delamination, corrosion) and provide real-time, depth sensitive C-scan information. This work is supported in part by the Navy SBIR program. M.Lasser, G. Harrison, Maryland | |||||
| UT Array | Turbine Blade Attachment In Service
Inspection through the Central Bore
using Ultrasonic Array Technology [A] Experience has shown that thermal stress cracking can occur in High and Medium Pressure Rotor blade attachments (tangencial T-Slot and axial trees steeples type). For this reason, in recent years diferent manufacturers have recommended regular inspections to keep track of the problem. This paper presents the on-site validation in real conditions of the S.I.R.E.N.A. system ," ROBOTIZED INSPECTION SYSTEM OF BLADES ATTACHMENTS USING ARRAY TECHNIQUE ", performed at the high-pressure turbine rotor of the Anllares Thermal Plant, in May 1996. A. Tanarro; F. Godinez; P. Serrano (TECNATOM,S.A.- MADRID-Spain) | 
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| UT Array | Ultrasonic Inspection of
Complex Nozzles -
Application of new Technologies [A] The inspection of the inner radius areas of the nozzles in the BWR reactor vessels, in addition the problems of access to these areas and their radiological conditions, present other difficulties resulting from the complexity of their geometry. The supposed orientation of the possible defects adds a new difficulty to the automatic inspection of these areas. The new ultrasonic inspection techniques, developed by new equipment and reinforced by ARRAY technology, have made it possible to advance in the field of defect characterization, localization and sizing of these components. This report represents the recent development realized by TECNATOM for inner radius inspection of the Boiling Water Reactor Vessel. A. Tanarro and A. Garcia (TECNATOM,S.A.-MADRID-Spain) | |||||
| UT Transducer Patents |
Patent Search on Ultrasonic Transducers and Arrays Access to abstracts of more than 400 Patents in this field. We used the US Patent Bibliographic Database, a freely searchable database of front page information from US patents issued from 1976 to 1998. UT | Library
NDTnet Resources of Ultrasonic Transducers and Arrays ( All former Articles etc.) | We updated the Transducer Workshop Library of originally published in Sept '96. NDT | Archaeo- technology
The Royal Mail Ship Titanic: Did a Metallurgical Failure Cause a
Night to Remember? | Standard metallographic techniques were used to prepare specimens taken from the hull plate of the Titanic for optical microscopic examination and scanning electron microscopy (SEM). Furthermore Energy-dispersive x-ray analysis (EDAX) identified MnS particles. As destructive testing methods were used Charpy Impact Tests and Tensile Testing. The article is an online version of the journal JOM, 50 (1) (1998), pp. 12-18. 
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