Phased array ultrasonic testing (PAUT) has become very prevalent in many aerospace applications. There is already a fair amount of literature regarding this inspection method for homogeneous material such as metals; however, much less information is available concerning composite materials. In composite applications, the use of beam steering can be somewhat limited due to the non-homogeneous properties of the structure. This paper will explore general principles for using PAUT on carbon fiber reinforced polymer (CFRP). Included in this topic will be beam steering techniques used for a single sided pulse echo (PE) inspection. The beam steering will be applied to a composite structure that has a sloped back surface ramp which is non-parallel to the entry surface of the ultrasound. General variables for the beam steering will be explored such as ramp slope and electronic focusing. Since C-scans are frequently used to interpret inspection data in a manufacturing environment, evaluation of the beam steering data within the C-scan will also be discussed. With this in mind, this literature will provide valuable insight and background information for using PAUT on composite structures.
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