Loop punching and bubble rupture causing surface roughening —A model for W fuzz growth
Association Euratom-Tekes, Department of Physics - P.O. Box 43, FI-00014 University of Helsinki, Finland
Received: 15 November 2013
Accepted: 16 January 2014
We develop a multi-scale computational model for studying tungsten fuzz formation under low-energy He irradiation. The molecular dynamics and kinetic Monte Carlo results show that the W fuzz growth mechanism is the following: the He atoms are trapped in W, forming bubbles and causing growth by loop punching. The bubbles close to the surface rupture. The balance between these processes leads to a stochastic surface growth, causing the surface roughness and fuzz thickness growth to scale as . The growth rates agree with the experimental results.
PACS: 52.40.Hf – Plasma-material interactions; boundary layer effects / 28.52.Fa – Materials / 61.43.Bn – Structural modeling: serial-addition models, computer simulation
© EPLA, 2014