| Abstract Scope |
Conventional 17-4PH stainless steels, when processed additively, produce microstructures that vary dramatically due to slight changes in processing parameters or composition within the specifications, leading to unpredictable mechanical properties. To address this challenge, a new variant of this steel, QT17-4+, has been designed by QuesTek Innovations LLC specifically for additive manufacturing, which demonstrates relatively consistent properties across a wide range of processing parameters and compositions. Unlike its conventional counterpart, which relies on Cu nanoprecipitates for secondary hardening, QT17-4+ achieves high strength through the formation of epsilon carbides, eliminating the need for high-temperature post-processing treatments. In this study, we investigate the microstructure and mechanical properties of this martensitic stainless steel processed additively with selective laser melting (SLM), employing synchrotron X-ray diffraction, electron back-scatter diffraction, atom-probe tomography, and tensile testing at ambient temperatures. |