A Novel Instrument for the Control of a Phased Array for NDE

Abstract

A low cost instrument to control a phased array for NDE is described. It uses a monolithic array fabricated on a PZT substrate and designed for the contact testing of steel at 5 MHz. A microprocessor, an IBM FC, controls the system for both the firing of the array elements and the subsequent processing of received data prior to its display. A CCD delay line is used in a novel manner to acquire the data by the application of a type of quadrature sampling, providing an effective sampling frequency of 50 MHz. Factors influencing the design of the array are described with experimental results being presented.