| About this Abstract |
| Meeting |
2025 TMS Annual Meeting & Exhibition
|
| Symposium
|
Designing Complex Microstructures through Additive Manufacturing
|
| Presentation Title |
In situ Evolution and Control of Austenite Reversion during Laser Powder Bed Fusion of 420 Stainless Steel |
| Author(s) |
William Hearn, Steve Gaudez, Florencia Malamud, Andac Özsoy, Steven Van Petegem |
| On-Site Speaker (Planned) |
William Hearn |
| Abstract Scope |
During laser Powder Bed Fusion (L-PBF) AISI 420SS forms a hierarchical microstructure of austenite and tempered martensite. For this alloy, optimizing the final austenite content is crucial for mechanical properties as this enhances the transformation induced plasticity effect. Typically, this is achieved by post-processing, however there is the potential to control this by adjusting process parameters. The current study aims to understand the evolution of austenite reversion during L-PBF and how this can be controlled. To achieve this, operando x-ray diffraction and quasi in situ neutron diffraction measurements were conducted at DESY and SINQ respectively. For these experiments, custom-built L-PBF machines for large-scale facilities were used to follow austenite reversion within the heat affected zone and specimen bulk. These results helped indicate the dominant form of austenite reversion during L-PBF. Additionally, they outline how the final austenite content can be controlled by adjusting the processing parameters. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Additive Manufacturing, Phase Transformations, Iron and Steel |