Method of detecting a change in the structure of a complex shape article

摘要

A method of detecting the change in the structure of a turbine rotor uses the steps of injecting an ultrasonic signal into the turbine rotor at a first position using a first ultrasonic transducer to produce a diffuse field ultrasonic signal in the rotor; detecting the signal in the rotor at a second position using a second ultrasonic transducer measuring the time for the signal to travel from the first ultrasonic transducer to the second ultrasonic transducer and comparing the measured time for the diffuse field ultrasonic signal to travel from the first ultrasonic transducer to the second ultrasonic transducer with a stored time for the diffuse field ultrasonic signal to travel from the first ultrasonic transducer to the second ultrasonic transducer to determine if there is a change in the structure of the turbine rotor.