Enhanced strength of additively manufactured Inconel 718 by means of a simplified heat treatment strategy

This study optimized the heat treatment process for laser powder bed fusion IN718, reducing post-processing time while maintaining beneficial microstructures and improving tensile strength. A simplified route combined stress relief, HIP, and solution treatment into a single pre-aging step, followed by a single-step aging treatment, cutting total heat treatment time from 42 h to 15 h. The novel HIP1020RQSA process used high pressure (200 MPa), a short soak at 1020 °C (0.5 h), and rapid quenching (2150 °C/min). This approach led to localized recrystallization, pore closure, partial Laves phase dissolution, and no δ phase. It improved yield strength from 1112 MPa to 1209 MPa while maintaining ASTM F3055–14a standards.