We describe the design and construction of a relatively simple, inexpensive laser interferometer system for accurate measurements of ultrasonic surface displacement waveforms in reasonably friendly environments. We show how analysis of a single waveform can provide both the calibration constant required for absolute measurements and an estimate of the uncertainty of these measurements. We demon...

This contribution describes a computationally efficient ray tracing algorithm for evaluating transducer generated ultrasonic wave fields in anisotropic materials such as austenitic cladded and austenitic weld components. According to this algorithm, ray paths are traced during its propagation through various layers of the material and at each interface the problem of reflection and transmission...

This paper describes the work done in an attempt to integrate ultrasonic sensors in micro-fluidic channels. We have developed a system with fluidic channels having embedded zinc oxide transducers. A zinc oxide film is deposited on a glass substrate and is sandwiched between two electrodes. The transducers made are found to resonate at 400 MHz in thickness mode. The channels are made both from P...

Prototype ultrasonic NDT transducers for use in immersion in coolants for small modular reactors have shown low signal to noise ratio. The reasons for the limitations in performance at high temperature are under investigation, and include changes in component properties. This current work seeks to quantify the issue of thermal expansion and degradation of the piezoelectric material in a transdu...

Piezoelectric single crystals, which have excellent piezoelectric properties, have extensively been employed for various sensors and actuators applications. In this paper, the state-of-art in piezoelectric single crystals for ultrasonic transducer applications is reviewed. Firstly, the basic principles and design considerations of piezoelectric ultrasonic transducers will be addressed. Then, th...

Accurate fluid flow metering is essential for modern process control, and ultrasonic flow meters are well established in this area. However, the specific acoustic impedance mismatch for most piezoelectric ultrasonic transducers is different when operating liquids and gases, hence there are problems measuring two-phase flows when using a single type of piezoelectric transducer in a flow meter. T...

Experience from the ultrasonic inspection of nuclear power plants has shown that large focused transducers are relatively effective in suppressing material structure noise. Operation of a large focused transducer can be thought of as integration (coherent summation) of individual beams reflected from the flaw and received by individual points at the transducer surface. Synthetic aperture focusi...

Surface mount technology has spurred a rapid decrease in the size of electronic packages, where solder bump inspection of surface mount packages is crucial in the electronics manufacturing industry. In this study we demonstrate the feasibility of using a 230 MHz ultrasonic transducer for nondestructive flip chip testing. The reflected time domain signal was captured when the transducer scanning...

The overall performance of sandwiched ultrasonic transducers can be substantially degraded due to defects. Model-based diagnosis can be an attractive technique for monitoring the performance of sandwiched ultrasonic transducers. Using electromechanical models of the transducer, most parameters of the system can be determined based on measurements of electrical input quantities only. This contri...

In this paper, a micro ultrasonic motor using a micro-machined bulk piezoelectric transducer is introduced. The cylindrical shaped bulk piezoe t U e ©