Laser Ultrasonic Strength Validation of Additive Manufactured Parts

Metal parts produced by additive manufacturing (AM) are scanned by computed tomography (CT) for non-destructive evaluation (NDE) to predict mechanical failure due to defects. The scans, however, require expensive equipment, substantial time, and experienced operators to run, and are difficult to properly evaluate for complex parts. We propose to replace CT with laser ultrasonic testing (LUT) as the only viable NDE alternative that can be performed in-line during the AM build. This gives close access to defects for detection, and so corrective measures can be taken before they are covered over by further deposition, or they can be scrapped early, and thus reduces cost, time, and complexity. We will show that LUT will also, like CT, predict mechanical failure. In this Phase I project we will develop metrics that effectively summarize LUT characterization of defects in AM parts, and will develop LUT data processing to calculate these metrics. We will empirically establish a statistical correlation between these metrics and mechanical strength as found by tests-to-failure of simple AM parts, and will develop a Phase II plan. We expect to reach TRL 4 by the end of Phase I, and will identify potential markets and partners for further development. Approved for Public Release | 20-MDA-10643 (3 Dec 20)