About this Abstract |
Meeting |
MS&T24: Materials Science & Technology
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Symposium
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Fracture in Metals: Insights from Experiments and Modeling Across Length and Time Scales
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Presentation Title |
Atomistic Studies of Hydrogen Effects on Cross-slip in Ni and Fe70Ni10Cr20 |
Author(s) |
Xiaowang Zhou, Fernando León-Cázares, Christopher San Marchi |
On-Site Speaker (Planned) |
Xiaowang Zhou |
Abstract Scope |
Cross-slip energetics plays an important role on strength and toughness of metals. Hydrogen effects on cross-slip are of particular interest for hydrogen-mediated plasticity and hydrogen-assisted fracture. Past atomistic studies of cross-slip primarily use molecular statics to calculate the energy barrier of cross-slip from the lowest energy paths, or molecular dynamics to calculate cross-slip rates at different temperatures and fit the energy barrier to an Arrhenius equation. The challenge with the first method is that numerical methods are not effective to determine the lowest energy paths when many atoms are involved, and the challenge with the second method is that the cross-slip rates cannot be determined with sufficiently small error margins. Here we developed a third method to calculate cross-slip energy barriers using time-averaged molecular dynamics, and applied it to nickel and Fe70Ni10Cr20 at different hydrogen concentrations. The advantage of this new method and outcomes will be discussed in this presentation. |