The estimation of the time of arrival (TOA) and/or time of flight of the ultrasonic echoes is essential in ultrasonic nondestructive evaluation. In this paper, matching pursuit method has been used to analyze noisy ultrasonic pulse-echo wavelet and decompose the noisy pulse-echo wavelet into unit-norm vectors. The error ratio of the mean square is used to monitor the acceptability of the unit-n...

Ultrasonic imaging for nondestructive evaluation (NDE) applications is an important process for industrial applications. Understanding the material structure is an integral part of the manufacturing as well as maintenance operations. Especially for the critical industries like airlines where each component of the aircraft is required to perform at its best. One way to analyze material samples f...

We present a theoretical study on the tunability of phononic band gaps in two-dimensional phononic crystals consisting of various anisotropic cylinders in an isotropic host. A two-dimensional plane-wave expansion method was used to analyze the band diagrams of the phononic crystals; the anisotropic materials used in this work include cubic, hexagonal, trigonal, and tetragonal crystal systems. B...

Comprehensive and accurate inspections of welded components have become of increasing importance as NASA develops new hardware such as Ares rocket segments for future exploration missions. Simulation and modeling will play an increasing role in the future for nondestructive evaluation in order to better understand the physics of the inspection process, to prove or disprove the feasibility for a...

Related Articles Quantitative evaluation of hidden defects in cast iron components using ultrasound activated lock-in vibrothermography Rev. Sci. Instrum. 83, 094902 (2012) Quantitative trap and long range transportation of micro-particles by using phase controllable acoustic wave J. Appl. Phys. 112, 054908 (2012) Nonlinear nonclassical acoustic method for detecting the location of cracks J. Ap...

A new method for detection and sizing of closed crack is described which uses transient waveform of subharmonics with half input frequency in ultrasonic nondestructive evaluation. In analogy to the resonant characteristics of vibration of bubbles in liquids, we formulate an equation for resonant excitation of subharmonics at partially closed cracks. The equation has been partially verified by c...

This paper describes a threefold method of testing the performance of an array-based ultrasonic tool for nondestructive testing of spot welds. The tool is described in its capabilities, use, and advantages over existing counterparts. Performance testing is not only described, but results from carrying out the testing are documented as well. The three performance testing methods include the use ...

The paper presents evaluation of correlations for calculation of concrete compression strength using nondestructive testing parameters for both impact and ultrasonic pulse methods, as listed in EN 13791:2007. This standard indicates procedures relating to compression strength determination in construction and building elements. These procedures relate to compression strength evaluation based ei...

The quality and degradation state of building materials can be determined by nondestructive testing (NDT). These materials are composed of a cementitious matrix and particles or fragments of aggregates. Sand/cement ratio (s/c) provides the final material quality; however, the sand content can mask the matrix properties in a nondestructive measurement. Therefore, s/c ratio estimation is needed i...