High throughput testing platform and application in wire arc additive manufactured superalloy: Anisotropy investigation and component qualification

Abstract

The rapid development of additive manufacturing requires quick and cost-effective testing techniques for efficient materials, process, and product qualification. In this study, a high-throughput (HTP) tensile testing rig with capability of automatically testing 60 specimens per hour is developed, which is orders of magnitude faster than traditional one-at-a-time tensile testing. The HTP testing was utilized to investigate the anisotropy and intrinsic scattering of the mechanical properties for superalloy IN617 manufactured by wire arc additive manufacturing (WAAM), in an effort to qualify the WAAM process and an actual component. 120 samples were extracted from WAAM-built qualification bulk at 3 heights (bottom, middle, and top) and 2 orientations (Y and Z) and 40 samples were extracted from a load collar (an actual gas turbine component) for HTP testing. This large dataset was statistically analyzed and revealed that the Z-direction had significantly higher elongation than Y-direction, but slightly lower ultimate tensile strength. Intrinsic scattering in the Y-direction was higher than in the Z-direction and increased with height, which agreed with microstructure variations examined by optical microscopy and scanning electron microscopy (SEM). It was concluded that the WAAM process and product met the internal design requirements with the consideration of the anisotropy and intrinsic scattering of tensile properties. Qualification requirements of AM material, process and components, and potential applications of HTP testing are also discussed.