In-Process and Final Non-destructive Inspection Methods of Additive Manufactured (AM) Simulated Aerospace Critical Parts

At present there are no reliable, cost-effective process control techniques to minimize defect production and for qualification of finished parts fabricated by additive manufacturing (AM). In our Phase I project we have demonstrated the feasibility of filling this gap by applying laser ultrasonic testing (LUT) for nondestructive evaluation of each AM deposited layer in real time as it is formed. This in-line inspection qualifies the part layer-by-layer, directs defect removal during the manufacturing process, and ensures qualified finished parts that require no further testing. In this proposed Phase II project we will advance our LUT system, completing development of the laser beam configuration and the signal-processing algorithms and automated software that will be optimized for the inspection of Air Force critical parts. We will design and assemble two prototype inspection systems that will be tested on a powder bed machine at the site of our subcontractor. The first prototype will be capable of detecting critical defects in linear, rectangular builds after deposition. The second prototype will be capable of inspecting builds during production, between layers, and will be able to detect defects in builds with complex, non-linear geometry, and will support automated detection and flagging of defects.