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An Overview of Recent Standard and Accelerated Molecular Dynamics Simulations of Helium Behavior in Tungsten.

ABSTRACT: One of the most critical challenges for the successful adoption of nuclear fusion power corresponds to plasma-facing materials. Due to its favorable properties in this context (low sputtering yield, high thermal conductivity, high melting point, among others), tungsten is a leading candidate material. Nevertheless, tungsten is affected by the plasma and fusion byproducts. Irradiation by helium nuclei, in particular, strongly modifies the surface structure by a synergy of processes, whose origin is the nucleation and growth of helium bubbles. In this review, we present recent advances in the understanding of helium effects in tungsten from a simulational approach based on accelerated molecular dynamics, which emphasizes the use of realistic parameters, as are expected in experimental and operational fusion power conditions.

SUBMITTER: Sandoval L

PROVIDER: S-EPMC6721179 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature

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An Overview of Recent Standard and Accelerated Molecular Dynamics Simulations of Helium Behavior in Tungsten.

Sandoval Luis L Perez Danny D Uberuaga Blas P BP Voter Arthur F AF

Materials (Basel, Switzerland) 20190807 16

One of the most critical challenges for the successful adoption of nuclear fusion power corresponds to plasma-facing materials. Due to its favorable properties in this context (low sputtering yield, high thermal conductivity, high melting point, among others), tungsten is a leading candidate material. Nevertheless, tungsten is affected by the plasma and fusion byproducts. Irradiation by helium nuclei, in particular, strongly modifies the surface structure by a synergy of processes, whose origin ...[more]

PMID: 31394714

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