5-6 MHz PMNT/epoxy 1-3 composites were prepared by a modified dice-and-fill method. They exhibit excellent properties for ultrasonic transducer applications, such as ultrahigh thickness electromechanical coupling coefficient k(t) (85.7%), large piezoelectric coefficient d33 (1209 pC/N), and relatively low acoustic impedance Z (1.82 × 107 kg/(m2·s)). Besides, two types of Time-of-Flight Diffract...

Abstract We present the design, prototype developments and test results of new time-of-flight detector (ToFD) which is part R $$^3$$ 3 B experimental setup at GSI FAIR, Darmstadt, Germany. The ToFD able to detect heavy-ion residues all charges relativistic energies with a r...

Welds have been inspected by radiography for years, but this technology has major drawbacks: low detection rates for critical planar defects (i.e. cracks and lack of fusion), subjective interpretation, no vertical sizing capability, significant safety hazards, licensing issues, plant closures, and generally slow inspection rates. For decades, the main alternative was manual ultrasonics, which i...

Abstract Welding technology is an important link in shipbuilding, and ultrasonic diffraction time difference method one of its inspection means, but the identification TOFD image still mainly relies on manual evaluation. In this paper, order to solve problems low accuracy unbalanced categories defect recognition existing automatic research, by reclassifying defects into primary defects, seconda...

TOFD technique is based on diffraction of ultrasonic waves on the tips of discontinuities instead of reflection on the interface of discontinuities. When ultrasound is incident at linear discontinuities such as crack diffraction takes place at its extremities in addition to the usual reflected wave. The diffracted energy is emitted over a wide angular range, presumed to originate at the extremi...

Time-of-Flight Diffraction (TOFD) is a relatively new method of ultrasonic inspection and is well suited to semiautomation using methods such as robotic scanning, computer conditioned data acquisition and signal and image enhancement. However very little work has been documented on the full computer understanding of such scans. Instead, most work has been directed at aiding the manual interpret...

Ultrasonic phased arrays are a new technology that offers considerable potential for inspecting construction welds. Using electronic control of the beam, phased arrays can scan, sweep, steer and focus the ultrasound. Since welds typically produce defects of known character and orientation, phased arrays can be programmed to optimize weld inspections. These inspections include standard ASME-type...