The increasing use in the industries of composite materials implies finding a suitable way for testing and evaluating them. Non-destructive testing by ultrasounds is an appropriate method to detect defects in this type of materials, however, because of their structure it is required to find the most applicable and accurate process for detecting flaws and anomalies in them. For conventional ultr...

Integrated (IUTs) and flexible ultrasonic transducers (FUTs) are presented for NDT at high temperatures. These transducers are made of sol-gel sprayed piezoelectric thick (> 40μm) ceramic films. The ceramic materials are lead-zirconate-titanate, bismuth titanate and lithium niobate which are for thickness measurement up to 150°C, 400°C and 800°C, respectively. The IUT can be also deposited onto...

Flexible ultrasonic transducers (FUTs) consisting of a 75 μm thick metal membrane, a piezoelectric composite with a thickness larger than 85 μm and a top electrode were developed for structural health monitoring (SHM) and non-destructive testing (NDT) applications. The piezoelectric films were made by a sol-gel spray technique. Its ultrasonic performance in terms of signal strength is at least ...

Ultrasonic tomography is an emerging technology that shows promise for quality assurance/quality control (QA/QC) during construction, or for making rehabilitation decisions in concrete pavements. However, the benefits of this emerging technology have not yet been fully captured for widespread use in highway infrastructure management. Verification of a state-of-the-art ultrasonic tomography devi...

to establish the location and shape of a Iiquid/vapor interface in a liquid container, thus enabling liquid A demonstration system for the ultrasonic gauging of volume measurement [I,21. fluids in low-gravity has been designed and tested. For purposes of simplification, it was assumed that vapor Typically, in propellant storage applications, the liquid within a liquid container in low-gravity w...

Ultrasonic Sensors in Air are Intelligent Sensors, which use wave-propagation phenomena in air to measure physical or chemical variables. With accordance to the influence principle, two main types of ultrasonic sensors can be differentiated. Propagation-Pafh Sensors decode changes on propagation to get a fast measurement of temperature, pressure variations or gas concentration. Most important a...

The AC response measurement system is presented. System structure, operation and main units operation are described. The connection setup for a few most common tasks is presented. The obtained results are given. It has been indicated that AC response can be investigated for ultrasonic preamplifier, matching transformer, system filters and ultrasonic transducers. The system is controlled by a pe...

Abstract: A pulse-echo technique, based on ultrasonic "long-bar" mode (LBM) velocity measurements, working up to 1700°C is described. Magnetostrictive transducers and ultrasonic lines used in a 40-85 kHz frequency range are detailed. The conditions of choice of fundamental parameters (frequency, line geometry, sample size) are discussed in relation with the nature and the microstructure of ...