Mapping of Materials Stress with Ultrasonic Tomography

It is _known _that internal stress concentrations can give rise to microcracks which then grow when the str~cture 1s subJected to external forces. It has also been found that the velocity'of sound is altered as ~t propagates through a region of stress. In this paper we discuss a technique called ComputerAsslsted Tomography (~AT) and describe ~n application that provides pictures of stress fields. We report the results of both s1mulated and exper1mental models used to evaluate the technique. We conclude that the CAT approach has great potential for locating and mapping residual stress in metals.