NDT for qualification of space hardware made by additive manufacturing

Abstract

X-Ray Computed Tomography (CT) has been established as the preferable NonDestructive Testing (NDT) method to detect inner defects in Metal Additive Manufactured (MAM) parts such as porosity, inclusions, lack of fusion, etc. Moreover, the usage of this manufacturing technology has grown in the aerospace sector due to the establishment of quality standards and the current maturity of the manufacturing systems, processing route and means of inspection. For instance, the European Cooperation for Space Standardization has developed a specific standard (coordinated by the European Space Agency – ESA) for AM quality assurance, processing, and requirements in space applications (ECSS-Q-ST-70-80C) indicating that CT inspections shall be carried out especially for critical structural and functional components. Similarly, large OEMs (Original Equipment Manufacturers) have developed their own standards considering CT as a mandatory NDT method in critical parts, but also other techniques such as Penetrant Testing (PT), Digital Radiography (DR) or visual inspection (VI) are also considered necessary to assure the quality of the components. This works presents diverse applications examples of different NDTs for hardware qualification: Titanium brackets for CHEOPS space missions; Aluminium helix antenna for PROBA3; Aluminium brackets for JUpiter ICy moons Explorer mission (JUICE), the last; or other aeronautic components like Aluminium fairings for the Clean Sky 2 IADP demonstrator, and structural Titanium flap fittings of the RACER helicopter. The aforementioned cases will be analysed not only from the execution of the inspection, but also from the application of different standards and requirements, specifically developed for AM or adapted to this novel manufacturing technology.