About this Abstract |
Meeting |
2022 TMS Annual Meeting & Exhibition
|
Symposium
|
Additive Manufacturing: Materials Design and Alloy Development IV: Rapid Development
|
Presentation Title |
In-situ Tempering of Ferrous Martensite during Laser Powder Bed Fusion |
Author(s) |
William Hearn, Kristina Lindgren, Eduard Hryha |
On-Site Speaker (Planned) |
William Hearn |
Abstract Scope |
To date, in-situ tempering of ferrous martensite during Laser Powder Bed Fusion (L-PBF) is a topic that remains poorly understood. This is primarily due to the non-equilibrium nature of L-PBF that leads to a complex thermal history. In this work, ferrous martensite in a L-PBF produced Fe-0.45C alloy was analyzed via hardness, OM, SEM, TEM and APT. These analyses found martensite to have a “quenched-like” state when initially deposited, with carbon segregating to lath boundaries and to dislocations. The most significant tempering of this “quenched-like” martensite occurred during subsequent layer melting, specifically within the heat affected zone. As said tempering led to the precipitation of vast carbide networks (at the lath boundaries) as well as a noticeable reduction in martensite hardness. |
Proceedings Inclusion? |
Planned: |
Keywords |
Additive Manufacturing, Iron and Steel, Characterization |