A 5 MHz high-voltage demultiplexed ultrasonic array system for rapid-scan testing of advanced materials

Abstract The most common techniques in non-destructive ultrasonic testing applications make use of the mechanical or manual scanning of the sensor devices. An important limitation of these procedures is the time required to acquire the inspection data when only a single transducer is scanned over the whole area of interest. To overcome this problem, a multichannel operation must be introduced. In this paper a 5 MHz array system of eight channels with electronic scanning through a high-voltage demultiplexer is presented. The system has been specially developed for rapid-scan purposes, needing only one commercial monochannel flaw detector as external equipment. The sensor device is a broad-band eight-element array transducer of multilayer type with one matching layer. A new analog demultiplexer has been designed, which is able to control the pass of broad-band pulses containing large peaks of voltage and current.