Application of ultrasonic computerized tomography using time-of-flight measured by transmission method to nondestructive inspection for high-attenuation billets

Abstract

For the nondestructive inspection of steel billets, the pulse echo method is generally employed in their manufacturing process. However, for high-attenuation billets, the pulse echo method is useless owing to the low echo level, while the transmission method is expected to detect defects inside high-attenuation billets. In this study, we consider the effectiveness of ultrasonic computerized tomography (CT) using time-of-flight (TOF) measured by the transmission method compared with the pulse echo method. From the simulation and experimental results, even though it was difficult for the pulse echo method to detect defects inside high-attenuation billets, the defects could be visualized by ultrasonic CT using TOF measured by the transmission method. Therefore, ultrasonic CT using TOF measured by the transmission method is more effective for detecting defects inside high-attenuation billets than the pulse echo method.

Compressive sampling–based ultrasonic computerized tomography technique for damage detection in concrete-filled steel tube in a bridge

“…Transducer and receiver are attached to each position of the measurement net for generating and receiving the ultrasonic waves. After discretized, Radon equation can be expressed as equation (2). The ToF of ultrasonic wave propagating along ith measurement path is calculated as follows…”

“…The transducer-receiver coupled array physically rotates around the structural component providing multiple pathways for ultrasonic propagations. [1][2][3] Ultrasonic wave interacts with the internal flaws and damage of the object being imaged. The characteristics of ultrasonic waves such as time-of-flight (ToF), magnitude, and attenuation carrying the damaged information can be reconstructed for imaging the internal damage in the structure.…”

“…The characteristics of ultrasonic waves such as time-of-flight (ToF), magnitude, and attenuation carrying the damaged information can be reconstructed for imaging the internal damage in the structure. 4,5 Norose et al 2 applied UCT technique using ToF measured by transmission method for the inspection of high-attenuation billets. Schabowicz 6 presents UCT as a suitable NDT technique for testing concrete members for locating defects and determining their sizes.…”

Improved Ultrasonic Computerized Tomography Method for STS (Steel Tube Slab) Structure Based on Compressive Sampling Algorithm

“…Ultrasonic CT is a digital imaging technique consisting of a numerically reconstructed inverse problem, which is associated with the interaction of ultrasonic waves with the detected structures [12][13][14]. The characteristics that define the reconstruction of the quantitative tissue for the diagnostic application can be the speed of sound, mass density, and attenuation [15].…”

Sol–gel composite material characteristics caused by different dielectric constant sol–gel phases

“…Ultrasonic transducers have been investigated in the field of nondestructive testing (NDT) applications, and they are expected to be used for the inspection of internal defects such as those in industrial structures. [1][2][3][4][5][6][7][8][9][10][11][12][13] Ultrasonic transducers made by the sol-gel spray technique have several benefits, such as curved surface suitability, high signal-to-noise ratio (SNR), broadband, and high temperature durability. [14][15][16][17][18][19][20][21][22][23][24][25] A sol-gel composite material is made of a mixture of ferroelectric powder and dielectric material sol-gel solution, and the combination of ferroelectric powder and sol-gel solution in the sol-gel composite method has been studied for the development of new composite materials with desirable characteristics.…”