2.2. LPBF Hastelloy X Specimens: Production and Geometrical Features

The HX specimens were fabricated from gas atomized HX powders supplied by LPW Technology (LPW Technology Ltd., Runcorn, UK) using an EOSINT M270 Dual Mode version (EOS GmbH, Munich, Germany) laser powder bed fusion machine, equipped with a Ytterbium 200 W fiber laser. Note that the process parameters are omitted to protect the proprietary information.

Cylindrical samples with a length of 77 mm and a diameter of 14 mm were built along the building direction (z-axis). The as-built HX specimens were cut into smaller samples with a length of 5 mm, and then the microstructure was investigated along the x-y plane, which is perpendicular to the building direction, and along the z-y plane, which is parallel to the building direction, as schematized in Figure 1.

Schematic representation of the as-built HX cylinders built along the building direction; the x-y plane is perpendicular to the building direction, while the z-y plane is parallel to the building direction.