1. Institute of Plasma Physics Hefei Institutes of Physical Science Chinese Academy of Sciences Hefei 230031 China; 2. University of Science and Technology of China Hefei 230026 China
Abstract:B4C was proposed as a material of in-situ protecting coating to avoid damages like erosion, cracking and particle emission on tungsten tiles of tokamak plasma facing components. This study involved the fabrication and adhesion testing of inductively coupled plasma (ICP) plasma sprayed B4C coating on tungsten (W) substrate. Coating optimization for B4C on different spray distances was performed. Adhesion test result reveals the tendency of the coating adhesion strength, which increases along with the increasing spray distance. The adhesion strength of the coating on optimized conditions is 5.32MPa. Coatings characterization was presented with scanning electron microscope (SEM) analysis, which further proves the result of adhesion strength. Phase and composition analyses show that the main phase and chemical composition of the boron carbide coating is not changed after ICP torch treatment.
[1] Davis J W, Barabash V R, Makhankov A, et al.Assessment of tungsten for use in the ITER plasma facing components[J]. Journal of Nuclear Materials, 1998, 263(4): 308-312. [2] Bolt H, Barabash V, Federici G, et al.Plasma facing and high heat flux materials-needs for ITER and beyond[J]. Journal of Nuclear Materials, 2002, 307(3): 43-52. [3] Makhlaj V A, Garkusha I E, Aksenov N N, et al.Dust generation mechanisms under powerful plasma impacts to the tungsten surfaces in ITER ELM simu- lation experiments[J]. Journal of Nuclear Materials, 2013, 438(S1): 233-236. [4] Krieger K, Geier A, Gong X, et al. Erosion and migration of tungsten employed at the main chamber first wall of ASDEX upgrade[J]. Journal of Nuclear Materials, 2003, 313-316: 327-332. [5] Ueda Y, Fukumoto M, Nishikawa M, et al. Surface studies of tungsten erosion and deposition in JT-60U[J]. Journal of Nuclear Materials, 2007, 363-365(1): 66-71. [6] Han Zenghu, Li Geyang, Tian Jiawan, et al.Microstructure and mechanical properties of boron carbide thin films[J]. Materials Letters, 2002, 57(4): 899-903. [7] Cavasin A, Brzeinski T, Grenier S, et al.W and B4C coatings for nuclear fusion reactors[C]//Thermal Spray: Meeting the Challenges of the 21st Century, Nice, France, 1998: 957-961. [8] Azizov E, Barsuk V, Begrambekov L, et al.Boron carbide (B4C) coating: deposition and testing[J]. Journal of Nuclear Materials, 2015, 463: 792-795. [9] Sezer A O, Brand J I.Chemical vapor deposition of boron carbide[J]. Materials Science and Engineering: B, 2001, 79(3): 191-202. [10] Torkkeli A.Kinetic investigation of chemical vapor deposition of B4C on tungsten substrate[J]. VTT Publications, 2003, 52(504): 3832-3838. [11] Torkkeli A.Mechanism studies on CVD of boron carbide from a gas mixture of BCl3, CH4, and H2 in a dual impinging-jet reactor[J]. VTT Publications, 2003, 55(3): 701-709. [12] Torkkeli A.Production of B4C coatings by CVD method in a dual impinging-jet reactor: chemical yield, morphology, and hardness analysis[J]. VTT Publications, 2003, 55(504): 13988-13992. [13] Airapetov A A, Begrambekov L B, Buzhinskiy O, et al.Boron carbide coating deposition on tungsten and testing of tungsten layers and coating under intense plasma load[J]. Physics of Atomic Nuclei, 2015, 78(14): 1640-1642. [14] Lin Chunming, Tsai H L, Yang Cheng.Effects of microstructure and properties on parameter optimi- zation of boron carbide coatings prepared using a vacuum plasma-spraying process[J]. Surface and Coatings Technology, 2012, 206(10): 2673-2681. [15] Zeng Yi, Lee S W, Ding Chuanxian.Study on plasma sprayed boron carbide coating[J]. Journal of Thermal Spray Technology, 2002, 11(1): 129-133. [16] Lin Chunming.Parameter optimisation of a vacuum plasma spraying process using boron carbide[J]. Journal of Thermal Spray Technology, 2012, 21(5): 873-881. [17] Salimijazi H R, Coyle T W, Mostaghimi J, et al.Microstructure of vacuum plasma-sprayed boron carbide[J]. Journal of Thermal Spray Technology, 2005, 14(3): 362-368. [18] Ghasemi R, Vakilifard H.Plasma-sprayed nanostru- ctured YSZ thermal barrier coatings: Thermal insulation capability and adhesion strength[J]. Ceramics International, 2017, 43(12): 8556-8563. [19] 戴栋, 宁文军, 邵涛, 等. 大气压低温等离子体的研究现状与发展趋势[J]. 电工技术学报, 2017, 32(20): 1-9. Dai Dong, Ning Wenjun, Shao Tao, et al.A review on the state of art and future trends of atmospheric pressure low temperature plasmas[J]. Transactions of China Electrotechnical Society, 2017, 32(20): 1-9. [20] 张凯, 王瑞雪, 韩伟, 等. 等离子体重油加工技术研究进展[J]. 电工技术学报, 2016, 31(24): 1-15. Zhang Kai, Wang Ruixue, Han Wei, et al.Progress of heavy oil processing by plasma technology[J]. Transactions of China Electrotechnical Society, 2016, 31(24): 1-15. [21] 张晓星, 肖焓艳, 黄杨珏. 低温等离子体处理SF6废气综述[J]. 电工技术学报, 2016, 31(24): 16-23. Zhang Xiaoxing, Xiao Hanyan, Huang Yangjue.A review of degradation of SF6 waste by low temper- ature plasma[J]. Transactions of China Electro- technical Society, 2017, 31(24): 16-23. [22] Jansson U, Carlsson J, Markert L C, et al.Phase- selective chemical vapor deposition of boron carbide by nucleation control on patterned substrates[J]. Journal of Vacuum Science & Technology A Vacuum Surfaces & Films, 1989, 7(6): 3172-3175. [23] 孙家枢, 郝荣亮, 钟志勇, 等. 热喷涂科学与技[M]. 北京: 冶金工业出版社, 2013. [24] Vardelle M, Fauchais P, Vardelle A, et al.Controlling particle injection in plasma spraying[J]. Journal of Thermal Spray Technology, 2001, 10(2): 267-284. [25] Pawlowski L.The science and engineering of thermal spray coatings[M]. 2nd ed. New Jersey: John Wiley & Sons, 2008. [26] Pierre L F, Joachim V R H, Maher I B. Thermal spray fundamentals[M]. New York: Springer, 2014. [27] Feng Z G, Domaszewski M, Montavon G, et al.Finite element analysis of effect of substrate surface roughness on liquid droplet impact and flattening process[J]. Journal of Thermal Spray Technology, 2002, 11(1): 62-68.