|About this Abstract
||2023 TMS Annual Meeting & Exhibition
||Phase Transformations and Microstructural Evolution
||Measurements of Retained Austenite in Additively Manufactured Nitrogen Atomized 17-4PH Stainless Steel
||James Zuback, Fan Zhang, Daniel Gopman, Mark Stoudt, Maureen Williams, Carelyn Campbell
|On-Site Speaker (Planned)
Additively manufactured nitrogen atomized 17-4PH stainless steel is known to retain significant amounts of austenite after heat treatments that are intended to produce a fully martensitic material. Since retained austenite affects strength, ductility, and aging kinetics, accurate quantification of retained austenite is essential for establishing process-structure-property links. Here, the evolution of retained austenite in nitrogen atomized 17-4PH is probed with multiple characterization techniques from the as-deposited material to the final solutionized condition for different alloy chemistries and powder bed fusion process parameters. Bulk and surface-based measurement techniques are employed to demonstrate the advantages and disadvantages with respect to their accuracy in determining phase fractions. Depending on alloy composition and heat treatment, the volume fraction of retained austenite is shown vary by a factor up to four across measurement techniques. Further, findings suggest a universal heat treatment may not be applicable for all powder feedstock and additive manufacturing process combinations.
||Additive Manufacturing, Iron and Steel, Phase Transformations