Monte Carlo simulation of ion–material interactions in nuclear fusion devices

ABSTRACT

One of the key aspects regarding the technological development of nuclear fusion reactors is the understanding of the interaction between high-energy ions coming from the confined plasma and the materials that the plasma-facing components are made of. Among the multiple issues important to plasma–wall interactions in fusion devices, physical erosion and composition changes induced by energetic particle bombardment are considered critical due to possible material flaking, changes to surface roughness, impurity transport and the alteration of physicochemical properties of the near surface region due to phenomena such as redeposition or implantation. A Monte Carlo code named MATILDA (Modeling of Atomic Transport in Layered Dynamic Arrays) has been developed over the years to study phenomena related to ion beam bombardment such as erosion rate, composition changes, interphase mixing and material redeposition, which are relevant issues to plasma-aided manufacturing of microelectronics, components on object exposed to intense solar wind, fusion reactor technology and other important industrial fields. In the present work, the code is applied to study three cases of plasma material interactions relevant to fusion devices in order to highlight the code’s capabilities: (1) the Be redeposition process on the ITER divertor, (2) physical erosion enhancement in castellated surfaces and (3) damage to multilayer mirrors used on EUV diagnostics in fusion devices due to particle bombardment.

KEYWORDS:

• Ion beam modification of materials
• plasma material interactions
• Monte Carlo simulations
• sputtering
• redeposition

PACS::

• 34.35.+a
• 61.80.Lj
• 52.40.Hf
• 02.70.Uu

Acknowledgements

The authors wish to thank J. Brooks for providing data on redeposition fractions and particle fluxes for the mixed material modeling, and the students G. Valiente, G. Flores, A. Torres y R. Morales for performing calculations presented in this work.

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

M. Nieto Perez http://orcid.org/0000-0001-6600-9786

Additional information

Funding

This work was supported by Instituto de Ciencia y Tecnología del Distrito Federal [grant number PIFUTP08].