Silicon carbide (SiC) represents a promising but largely untested plasma-facing material (PFM) for next-step fusion devices. In this work, an analytic mixed-material erosion model is developed by calculating the physical (via SDTrimSP) and chemical (via empirical scalings) sputtering yield from SiC, Si, and C. The Si content in the near-surface SiC layer is predicted to increase during D plasma bombardment due to more efficient physical and chemical sputtering of C relative to Si. Silicon erosion from SiC thereby occurs primarily from sputtering of the enriched Si layer, rather than directly from the SiC itself. SiC coatings on ATJ graphite, manufactured via chemical vapor deposition, were exposed to repeated H-mode plasma discharges in the DIII-D tokamak to test this model. The qualitative trends from analytic modeling are reproduced by the experimental measurements, obtained via spectroscopic inference using the S/XB method. Quantitatively the model slightly under-predicts measured erosion rates, which is attributed to uncertainties in the ion impact angle distribution, as well as the effect of edge-localized modes. After exposure, minimal changes to the macroscopic or microscopic surface morphology of the SiC coatings were observed. Compositional analysis reveals Si enrichment of about 10%, in line with expectations from the erosion model. Extrapolating to a DEMO-type device, an order-of-magnitude decrease in impurity sourcing, and up to a factor of 2 decrease in impurity radiation, is expected with SiC walls, relative to graphite, if low C plasma impurity content can be achieved. These favorable erosion properties motivate further investigations of SiC as a low-Z, non-metallic PFM.

碳化硅 (SiC) 是一种很有前途但在很大程度上未经测试的面向等离子体的材料 (PFM)，可用于下一步的聚变装置。在这项工作中，通过计算 SiC、Si 和 C 的物理（通过 SDTrimSP）和化学（通过经验缩放）溅射产率，开发了一种分析混合材料侵蚀模型。 预测了近表面 SiC 层中的 Si 含量由于 C 相对于 Si 的更有效的物理和化学溅射，在 D 等离子体轰击期间增加。因此，来自 SiC 的硅侵蚀主要来自富硅层的溅射，而不是直接来自 SiC 本身。通过化学气相沉积制造的 ATJ 石墨上的 SiC 涂层暴露于 DIII-D 托卡马克中的重复 H 模式等离子体放电以测试该模型。S / XB方法。从数量上讲，该模型略微低估了测量的侵蚀率，这归因于离子撞击角分布的不确定性以及边缘局部模式的影响。暴露后，观察到 SiC 涂层的宏观或微观表面形态变化很小。成分分析显示约 10% 的 Si 富集，符合侵蚀模型的预期。外推到 DEMO 型器件，如果可以实现低 C 等离子体杂质含量，则相对于石墨，SiC 壁的杂质来源会减少一个数量级，杂质辐射减少最多 2 倍. 这些有利的侵蚀特性促使进一步研究 SiC 作为低Z, 非金属 PFM。