|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||Additive Manufacturing: Building the Pathway towards Process and Material Qualification
||In-situ Neutron Diffraction Measurements for Isolating Microstructural Effects on Mechanical Properties of As-built AM 304L SS
||Reeju Pokharel, Anirban Patra, Don Brown, Bjorn Clausen
|On-Site Speaker (Planned)
Several additive manufacturing (AM) techniques exist that enable fabrication of metallic components with complex geometries. In AM materials, microstructures and properties are observed to be processing route dependent, which are significantly different from their wrought counterparts. In-situ neutron diffraction measurements were completed on post-build AM 304L stainless steel manufactured via directed metal laser sintering and laser engineering net shaping, using various feedstock. Post-processing heat treatment recipes were developed to isolate microstructural parameters such as phase fraction, dislocation density, and residual stresses that influenced post-build properties. Cooling simulations were performed using a thermo-mechanical crystal plasticity finite element framework, with consideration for individual austenite and ferrite properties, to study the effect of processing on the residual stresses in the as-built state. These residual stresses are manifested in both the measured and simulated coefficient of thermal expansion of the individual phases present in the material, with regards to deviation from the theoretical values.
||Planned: Supplemental Proceedings volume