Non-destructive Characterization of Ply Orientation and Ply Type of Carbon Fiber Reinforced Laminated Composites

As the fuel efficiency of vehicles is being increased over the next decade due to both consumer demand and regulations, several automobile manufacturers are incorporating fiber-reinforced composites into their product line due to their high strength to weight ratio. While the fiber-reinforced components are lighter than the traditional aluminum and steel components, the processing and repair of these parts is more complicated. The need for non-destructive testing methods to characterize the as-processed ply configuration compared to the as-designed ply configuration will become essential in next generation vehicle quality control and maintenance. Traditionally, ultrasonic techniques have been focused on locating defects and delaminations within parts. The current study incorporates a novel ultrasonic C-scanning technique to determine the ply type, orientation and thickness of each lamina in a carbon fiber reinforced laminated composite. Initial testing was performed inside of an immersion tank, but the system has since been reconfigured to a non-immersion system which can be placed on the top surface of the carbon fiber reinforced laminate for scanning. This paper presents the results for a variety of parts along with the accuracy associated with this non-destructive testing method.