Design and construction of short pulse ultrasonic probes for non-destructive testing

This paper describes the design and construction of 10 MHz compressional wave ultrasonic ndt probes for use in situations where operation with the shortest possible pulse length (and hence greatest bandwidth) is of prime importance. Tungsten-loaded epoxy backing blocks are manufactured separately before incorporation into probes, the manufacturing technique allowing lossy, high impedance backings to be constructed both with ease and with the use of very little manufacturing equipment. After preparation, transducers and backings are assembled into probes using simple construction jigs.Results are given showing that the 10 MHz probes thus constructed operate satisfactorily both in contact and in immersion testing. Probes of other centre frequencies can be manufactured using the same technique.