Nondestructive Evaluation (NDE) for In-Space and Additively Manufactured Materials/Structures

Despite enormous progress in metallic additive manufacturing (AM) process, one of the most notable needs is the industry agreement for the development of proper in-situ sensing methods and implementation of in-process sensors (monitoring/controlling) for product acceptance.nbsp;nbsp;Even though the usage of different signal processing techniques has greatly improved the defect tracking-learning-detection and classification performance, seldom are these methods robust and reliable enough to meet in-space standards and customers satisfaction. In order to develop reliable NDE in-process sensing and monitoring technologies for AM processes used to produce critical components for in-space applications, smart optical monitoring system based on spectroscopy is adopted and following technical challenges will be addressed by performing; (1) Understand the mechanism on how different composition, phase transformation and manufacturing defects affect the characterization of the laser/arc induced plasma; (2) Design effective algorithms and a seamless hardware digital signal processing unit that are able interpret the plasma signal for manufacturing quality prediction with high accuracy and reliability; and (3) Design a in-process monitoring / control system to adjust the manufacturing parameters to guarantee manufacturing quality.nbsp;nbsp;Thenbsp;approachnbsp;to tackle these challenges is to usenbsp;a good balance between understanding how different manufacturing defects, compositions and phase transformations affect the plasma characterization and the use of effective algorithm to interpret the change of plasma to reflect the defects.nbsp;nbsp;The successful execution of the tasks proposed will help us develop a smart sensor far beyond the available state-of-the-art technologies to provide in-situ and reliable prediction of composition, phase transformation and manufacturing defect that meets in-space application standards.