Erlangen 2026 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
P: Fachverband Plasmaphysik
P 16: Poster Session Plasma Physics
P 16.93: Poster
Thursday, March 19, 2026, 13:45–15:45, Redoutensaal
Study of boronization history effects on impurity control in Wendelstein 7-X — •Pei Ren1,3, Yunfeng Liang1,3, Shuai Xu1, Frederik Henke2, Alexander Knieps1, Maciej Krychowiak2, Birge Buttenschön2, Alice Bonciarelli2, Sebastijan Brezinsek1, Dorothea Gradic2, Daihong Zhang2, Carsten Killer2, Luo Yu1,3, Marcin Jakubowski2, Petra Kornejew2, and Erhui Wang1 for the w7-x team collaboration — 1Institute of Fusion Energy and Nuclear Waste Management, Forschungszentrum Jülich GmbH, Jülich, Germany — 2Max Planck Institute for Plasma Physics, Greifswald, Germany — 3Faculty of Mathematics and Natural Science, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
Boronization is routinely applied for wall conditioning on W7-X, significantly improving plasma performance. This work investigates the history effects on impurity control using visible and UV spectroscopy. Results show that boronization strongly suppresses oxygen impurities, and although this effect gradually weakens, overall impurity control remains robust. Spearman correlation analysis indicates that, over time, oxygen impurity radiation becomes decoupled from total radiation, while carbon sputtering reaches a steady state. Analysis of OP2.2 data under identical conditions 1 day, 2 days, and 2 weeks after fresh boronization shows consistent trends: oxygen radiation slightly increases over time but remains within controlled levels. These findings confirm that multiple boronizations effectively maintain good wall conditioning.
Keywords: Boronization; History effect; Impurity control; Oxygen impurity radiation; Spearman correlation analysis