Implantation and desorption of H isotopes in W revisited by object kinetic Monte Carlo simulation

As the leading candidate of plasma-facing materials, tungsten is expected to withstand the influx of D-T plasma in future fusion reactors, which is known to cause damages to tungsten surface and give rise to T fuel retention. In this work, based on accurate density functional theory parameterization, we carried out a series of object kinetic Monte Carlo (OKMC) simulations to study the retention behavior of H isotopes in W. By directly comparing our simulations with existing experiments, we show that the OKMC model can accurately describe H implantation and desorption behavior in W, with excellent agreements found between experimental/simulated H annealing curves, thermal desorption spectra, and fluence dependence. Our OKMC model reveals primary trapping sites of H in these experiments, provides deeper understanding for experimental results, and offers quantitative theoretical assessment for H implantation and desorption in W.(c) 2022 Elsevier B.V. All rights reserved.

Automated summary

In this study, we used accurate density functional theory parameterization to conduct object kinetic Monte Carlo simulations and investigate the retention behavior of H isotopes in tungsten. By comparing our simulations with existing experiments, we demonstrated the accuracy of the OKMC model in describing H implantation and desorption behavior in tungsten. The model revealed primary trapping sites and provided a deeper understanding of experimental results, while also offering a quantitative theoretical assessment for H implantation and desorption in tungsten.