Acoustical fields from rectangular ultrasonic transducers for non-destructive testing and medical diagnosis

Ultrasonic transducers are used in many fields of application, including medical imaging/treatment, non-destructive testing and material characterization. To assure the quality of the ultrasonic investigation transducers require regular checks for possible deterioration and accurate calibration. Current methods rely on point-by-point scanning of the ultrasound field with a needle hydrophone, which is expensive and time consuming. Recently, we have developed a new concept, in which a fast full-field visualization of the radiation field is achieved through Acoustically induced PiezoLuminescence (APL). Here, we report on an improved ultrasonic beam visualization and provide further insights into the mechanism underlying APL and mechanoluminescence.

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The application and limitation of the use of X-rays in medical diagnosis

Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences ◽

10.1098/rsta.1979.0048 ◽

1979 ◽

Vol 292 (1390) ◽

pp. 147-156 ◽

Cited By ~ 1

Keyword(s):

Medical Diagnosis ◽

Biological Material ◽

Chemical Elements ◽

Visual Image ◽

X Rays ◽

Non Destructive Testing ◽

Destructive Testing ◽

The Subject ◽

Non Destructive

X-rays in medical diagnosis are normally used to obtain a visual image of the subject radiographed. The image results from the differential attenuation of the radiation which depends on the thickness, density and configuration of the organ irradiated and on the proportion and nature of the different chemical elements present. The nature of biological material is such that the contrast differentiation between organs or parts of an organ is frequently poor and despite methods to increase the contrast this remains one of the principal limitations. Other limitations are similar in many respects to those found when using X-rays for non-destructive testing but additional limitations are imposed since when living subjects are examined, movement of the subject can seldom be eliminated and, because radiation may be harmful, the dose must always be kept as low as reasonably practical. Further constraints are imposed by the high cost of some equipment and the shortage of qualified manpower to operate the equipment and interpret the findings. The number and type of examinations carried out may have to be limited in some very sick patients because they reach their limits of endurance. Practically every procedure therefore has to be a compromise between the advantages and the limitations imposed.

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PVDF ultrasonic transducers for non-destructive testing

Ferroelectrics ◽

10.1080/00150199108222382 ◽

1991 ◽

Vol 115 (1) ◽

pp. 229-246 ◽

Cited By ~ 12

Author(s):

Michael Platte

Keyword(s):

Ultrasonic Transducers ◽

Non Destructive Testing ◽

Destructive Testing ◽

Non Destructive

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X-Ray Induced Acoustic Computed Tomography for Non-Destructive Testing of Aircraft Structure

Volume 1: Advances in Aerospace Technology ◽

10.1115/imece2019-10480 ◽

2019 ◽

Author(s):

Tiffany Tran ◽

Pratik Samant ◽

Liangzhong Xiang ◽

Yingtao Liu

Keyword(s):

Computed Tomography ◽

Simulation Study ◽

Acoustic Waves ◽

Imaging Technique ◽

Ultrasonic Transducers ◽

X Rays ◽

Non Destructive Testing ◽

Destructive Testing ◽

X Ray ◽

Non Destructive

Abstract For decades, aircraft disasters have always been a concern for airline companies and especially for consumers. Scientists all over the world have been constantly trying to study, discover and invent new methods for testing and prevention to reduce future aircraft accidents. One of those methods is non-destructive testing, which is a widely adaptive process for analyzing structural integrity over wide arrays of object. X-rays, ultrasound and computed tomography (CT) are non-destructive testing applications commonly used for the commercial aircraft maintenance. These non-destructive testing methods for aircraft structures give us high-quality images of structural damage but, there are some disadvantages related to resolution and the contrast mechanism of the image. The goal of this study is to demonstrate the concept of X-Ray Induced Acoustic Computed Tomography (XACT) imaging method for defect detection and localization through simulations using k-wave MATLAB toolbox. XACT is a technique based on the X-ray induced acoustic effect. In XACT, a short pulsed of X-rays are required to achieve thermal response and generate acoustic waves. X-ray travels to an object, the photons are absorbed causing the temperature in the object to raise, which generates acoustic waves due to thermoelastic expansion. These acoustic waves are then detected by ultrasonic transducers. Within the fuselage of the aircraft, the aircraft’s stiffener is designed using SolidWorks. along with two different types of defects through voids due to manufacturing imperfection process. As well as, cracks in the surface of the model due to mechanical failures are created in MATLAB. Two properties of Aluminum 6065 and Inconel 625 materials were selected for our simulation study since it is often used for the fuselage and/or aircraft engines. XACT images are generated under the combination of high X-ray absorption and ultrasonic transducers that will be able to overcome the disadvantages of the X-ray imaging technique and ultrasound imaging technique in image resolution and contrast mechanisms. The results from this simulation study demonstrate that the XACT method not only gives us high-resolution images but moreover, higher contrast of images that also allows us to detect position accuracy of the cons created.

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