|About this Abstract
||2022 TMS Annual Meeting & Exhibition
||Phase Transformations and Microstructural Evolution
||Cluster Evolution and Phase Transformation in Austenitic High-Cr Stainless Steel: A Comparison of Thin Film and Bulk Geometries
||Po-Cheng Kung, Jian-Min Zuo, Jessica Anne Krogstad
|On-Site Speaker (Planned)
To tailor the mechanical properties of metals to various use cases through precipitation hardening, it is crucial to understand how short-range structures evolve into precipitates in different condition. The present work investigates the effect of sample dimensions on the evolution of Cr short-range clusters in austenitic Fe-21Cr-6Ni-9Mn-0.3N stainless steel between 300-450 °C. A thin-film sample was heated in-situ at 450 °C in TEM, revealing that sphere-like Cr clusters, which were found in steel before heating, developed facets and transformed into the MgCu2 Laves phase. This was confirmed through in-depth diffraction analysis and high-resolution electron microscope images. On the contrary, bulk steel sample heated in a furnace presented an alternative phase transformation product and no faceting. For both samples, the cluster structures and the strain fields they induced were probed by 4D-STEM to understand the phase transformation and potential strengthening mechanisms of this steel.
||Iron and Steel, Phase Transformations, Characterization