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Late News Poster Session: Mechanics & Structural Reliability
Program Organizers: TMS Administration

Monday 5:30 PM
February 28, 2022
Room: Exhibit Hall C
Location: Anaheim Convention Center

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G-34: Strain-dependent Dislocation Density Formation in 4130 Steel Studied by Neutron Diffraction: Zachary Buck¹; Matthew Connolly¹; May Martin¹; Damian Lauria¹; Peter Bradley¹; Yan Chen²; Andrew Slifka¹; ¹National Institute of Standards and Technology; ²Oak Ridge National Laboratory
    Interrupted tensile tests were performed at the National Institutes of Standards and Technology on AISI 4130 steel in air and in hydrogen at 2600 psi. Investigation by neutron diffraction of the deformed specimens reveal a partitioning of ferrite and martensite phases as a function of applied strain. Dislocation densities of the two individual phases were extracted by analyzing the Bragg peak broadening using a Williamson-Hall approach. A phase transformation from predominantly martensitic steel to ferritic steel was also observed as a function of applied strain. These results demonstrate our ability to fabricate specimens with desired dislocation densities in air and in hydrogen environments, which will be useful in upcoming quasielastic neutron scattering experiments aimed at quantifying hydrogen diffusion as a function of dislocation density.

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