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Elseiver. Fusion Engineering and Design 85 (2010) 1999–2004. A carbon fiber composite (CFC) was thermally tested with high heat flux on a high-intensity pulsed ion beam (HIPIB) apparatus, simulating the ITER specific thermal impacts in divertor region during normal operation or on first wall during off-normal events. The HIPIB shot is capable of delivering an extremely high heat flux onto the target materials at a heat flux parameter of up to 300MW/m2 s1/2 covering most of the ITER heat loads. The surface morphology of CFC samples after the HIPIB exposure and the resultant weight losses were investigated using scanning electron microscope (SEM) and microelectronic balance, respectively. Moreover, Raman spectroscopy was used to study the microstructural changes of the exposed samples. Comparative tests were also carried out on pure graphite samples. It is found that the CFC samples underwent a severer net weight loss in comparison with the graphite under multi-shot exposure, where the material removal from the CFC proceeded in the form of carbon fibre exfoliation and/or fracture along with matrix spallation as the high heat flux exposure prolonged up to 10 shots. The fibre erosion process is attributable to the anisotropic thermophysical properties of carbon fibre and its interface bonding strength with graphite matrix though the reinforcing carbon fibre ensures excellent high-temperature strength of the CFC over the graphite.
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Fusion Engineering and Design 85 (2010) 1999–2004 Contents lists available at ScienceDirect Fusion Engineering and Design journal homepage: www.elsevier.com/locate/fusengdes Fiber erosion of carbon fiber composite exposed to simulated ITER-relevant thermal impact by high-intensity pulsed ion beam X.P. Zhu, Y. Tang, X. Wang, M.K. Lei ∗ Surface Engineering Laboratory, School of Materials Science and Engineering, Dalian University of Techology, Dalian 116024, China a r t i c l e i n f o Article history: Available online 17 August 2010 Keywords: Plasma facing materials Carbon fibre composite High heat flux testing High-intensity pulsed ion beam a b s t r a c t A carbon fiber composite (CFC) was thermally tested with high heat flux on a high-intensity pulsed ion beam (HIPIB) apparatus, simulating the ITER specific thermal impacts in divertor region during normal operation or on first wall during off-normal events. The HIPIB shot is capable of delivering an extremely high heat flux onto the target materials at a heat flux parameter of up to 300 MW/m2 s1/2 covering most of the ITER heat loads. The surface morphology of CFC samples after the HIPIB exposure and the resultant weight losses were investigated using scanning electron microscope (SEM) and microelectronic balance, respectively. Moreover, Raman spectroscopy was used to study the microstructural changes of the exposed samples. Comparative tests were also carried out on pure graphite samples. It is found that the CFC samples underwent a severer net weight loss in comparison with the graphite under multi-shot exposure, where the material removal from the CFC proceeded in the form of carbon fibre exfoliation and/or fracture along with matrix spallation as the high heat flux exposure prolonged up to 10 shots. The fibre erosion process is attributable to the anisotropic thermophysical properties of carbon fibre and its interface bonding strength with graphite matrix though the reinforcing carbon fibre ensures excellent high-temperature strength of the CFC over the graphite. © 2010 Elsevier B.V. All rights reserved. 1. Introduction Excellent heat resistance and high-temperature strength against the thermal loads from high-density charged particle impact is one of the most critical concerns in developing of plasma facing materials (PFMs) for thermonuclear fusion devices. To evaluate the mat