碳化矽複合材料在高溫下之機械性質、化學性質穩定與抗輻照活性的特點被認為是相當具有潛力發展於核融合反應器第一面牆的材料，然而第一面牆之材料需承受高溫且高劑量的照射，而奈米晶粒材料(Nanocrystalline Material)應用於核能環境下之自癒效應(self-healing effect)，可能是改善承受高輻射劑量材料的新方向，近年來被大量討論，而本論文則是利用SA-Tyrannohex全纖維複合材料進行氦、矽單雙射束實驗，觀察空泡缺陷的生成行為，與單晶材料之結果做比較，探討晶界對空泡抑制的成效為何。
本論文利用SA-Tyrannohex全纖維碳化矽複合材料進行單射束矽離子、氦離子及氦、矽離子雙射束佈值，且佈值溫度皆為高溫(>1073K)環境。SA-Tyrannohex全纖維碳化矽複合材料在單射束矽離子輻照20dpa，1200 ℃下並未觀察到空孔(void)，而SA-Tyrannohex全纖維碳化矽複合材料，在低劑量(15000appm)單射束氦離子輻照未觀察到氦氣泡生成於材料中，然而在高劑量(45000appm)之佈值情況下可觀察到氣泡生成，對比單晶碳化矽於同低劑量下觀察到氦氣泡，且高劑量下所觀察到的氣泡密度高出多晶複合材料一個數量級。回顧過去文獻，比較CVD多晶碳化矽、CVI多晶碳化矽材料與Hi-Nicalon Types 纖維於本論文相符劑量下之氣泡尺寸密度，可觀察到晶粒尺寸越小(晶界面積越大)在高溫情況下有抑制空泡生成的趨勢。

Silicon carbide compoiste is a promising material for first wall and blanket components in fusion reactors due to the great strength and low radioactivity under high temperature environment. Besides, several studies have shown that nanocrystalline materials can enhance the irradiation tolerance by enhancing defects recovery via interfaces and grain boundaries. However, it is not for sure that the realationship of small grian size SiC can suppress the cavities formation or not. Furthermore, the detail of grain size effect on irradiation induced defects should be understood.
In this work, SA-Tyrannohex all fiber SiC composite was irradiated by Si2+ single beam ,He+ single beam that the helium accmulation concentration up to 45000appm and Si/He dual beam condition. All of the iradiation condition were conducted at high temperature environment(>1073K).The microstructure evolution of irradiated SiC was examined by transmission electron microscopy.
Cavities can be observed in dual beam irradiated SA-Tyrannohex SiC composite specimens and 45000appm He implanted specimens. Comparison to single crystal SiC, CVD polycrystalline SiC and CVI polyctstalline SiC irradiated in the same condition ,SA-Tyrannohex all fiber SiC appears to have excellent radiation tolerance under high temperature condition by suppressing the cavities formation.Besides, grain boundaries seems to hava a capability to enhance the point defects recombination.

[1] IEA, 2014 Key World Energy STATISTICS , Aug. 2014
[2] IPCC, Summary for Policymakers. In: Climate Change 2014: Mitigation of Climate Change, 2014
[3] 李敏, 合理、實際的做法-核能，不能輕言放棄的選擇,四十二卷第二期,科學月刊,2011
[4] Donald R. Olander, Fundamental Aspects of Nuclear Reactors Fuel Elements, 1976
[5] Farrokh Najmabadi et al. , The ARIES-AT advanced tokamak, Advanced technology fusion power plant, 2006
[6] M. Mehregany, C.A. Zorman, "SiC MEMS: opportunities and challenges for applications in harsh environments", Thin Solid Films, 355-356, 1999, 518-524
[7] 林博文, 碳化矽及其他碳化物, 陶瓷技術手冊(下)修訂版,1999. , 745-776
[8] J. Eid, I. G. Galben, “3C-SiC growth on Si substrates via CVD: An introduction”, NOVASiC, 2008
[9] Stefanos Mourdikoudis , Konstantinos Simeonidis, Advanced characterization of 3C-SiC epitaxial layer by TEM and XRD pole figure, NOVASiC, 2008
[10] 尹衍升，氧化鋯陶瓷及其複合材料，2004，化學工業出版社
[11] Krishan K. Chawla, Composite Materials, 2nd edition, 1998, Springer
[12] Michio Takeda, Yoshikazu Imai, Hiroshi Ichikawa, Noboru Kasai, Tadao Seguchi, Kiyohito Okamura, Comp. Sci. Tech. 59 ,1999, 793-799.
[13] Michio Takeda, Akira Urano, Jun-ichi Sakamoto, Yoshikazu Imai, J. Nucl. Mater. 258-263 ,1998, 1594-159.
[14] A. Hasegawa, A. Kohyama, R. H. Jone, L. L. Snead, B. Riccardi, P. Fenici, “Critical issues and current status of SiC/SiC composites for fusion”, Journal of Nuclear. Materials, 283-287 ,2000, 128-137.
[15] Toshikatsu Ishikawa, “Recent developments of the SiC fiber Nicalon and its composites, including properties of the SiC fiber Hi-Nicalon for ultra-high temperature”, Comp. Sci. Tech. 51, 2, 1994,135–144
[16] Toshikatsu Ishikawa, “Recent developments of the SiC fiber Nicalon and its composites, including properties of the SiC fiber Hi-Nicalon for ultra-high temperature”, Comp. Sci. Tech. 51, 2, 1994,135–144
[17] Michio Takeda, “Microstructure and oxidative degradation behavior of silicon carbide fiber Hi-Nicalon Type S”, Journal of Nuclear Materials, 258–263 ,1998, 1594–1599
[18] Hiroshi Araki, Hiroshi Suzuki, Wen Yang, Shinji Sato, Tetsuji Noda, “Effect of high temperature heat treatment in vacuum on microstructure and bending properties of SiCf/SiC composites prepared by CVI”, Journal of Nuclear Materials, 258-263 ,1998, 1540-1545.
[19] A.Kohyama , Y. Katoh , L.L. Snead and R.H. Jones . “Development of SiC/SiC Composite for Fusion Application”.
[20] R. Yamada, T. Taguchi, N. Igawa, “Mechanical and thermal properties of 2D and 3D SiC/SiC composites” Journal of Nuclear Materials, 283-287 2000 ,574-578
[21] J. W. Warren, Ceram. Eng. Sci. Proc., 1985
[22] T.M. Besmann, B.W. Sheldon, R.A. Lowden, D. P. Stinton, “Vapor-Phase Fabrication and Properties of Continuous-Filament Ceramic”. Composites Science, Vol. 253, 1991
[23] Y. Katoh, A. Kohyama, Introduction to Fusion Reactor Engineering.
[24] J. J. Brennan, “INTERFACIAL CHARACTERIZATION OF A SLURRY-CASTMELT-INFILTRATED SiC/SiC CERAMIC-MATRIX COMPOSITE” Acta MATERIALIA. 48,2000, 4619-4628.
[25] S. P. Lee, Y. Katoh, J. S. Park, S. Dong, A. Kohyama, S. Suyama, H. K. Yoon, “Microstructural and mechanical characteristics of SiC/SiC composites with modified-RS process” Journal of Nuclear Materials, 289 ,2001, 30-36.
[26] S. P. Lee, Y. Katoh, A. Kohyama, “Microstructure analysis and strength evaluation of reaction sintered SiC/SiC composites” Scripta mater. 44 ,2001, 153-157.
[27] Y Katoh, S.M Dong, A Kohyama, “Thermo-mechanical properties and microstructure of silicon carbide composites fabricated by nano-infiltrated transient eutectoid process”, Journal of Fusion Engineering and Design, 61–62, 2002, 723–731
[28] K. Shimoda, Akira Kohyama, Tatsuya Hinoki, “High mechanical performance SiC/SiC composites by NITE process with tailoring of appropriate fabrication temperature to fiber volume fraction”, Composites Science and Technology, 69,, 2009,1623–1628
[29] A. Kelly, C. Zweben (Eds.), Comprehensive Composite Materials, vol. 4, Elsevier Science, Amsterdam, 2000.
[30] Y. Katoh , A. Kohyama, T. Nozawa, M. Sato, “SiC/SiC composites through transient eutectic-phase route for fusion applications”, Journal of Nuclear Materials, 329–333 ,2004, 587–591
[31] T. Hinoki, W. Zhang, A. Kohyama, S. Sato, T. Noda, “Effect of fiber coating on interfacial shear strength of SiC/SiC by nano-indentation technique” Journal of Nuclear Materials, 258-263, 1998, 1567-1571
[32] C. A. Lewinsohn, R. H. Jones, G. E. Youngblood, C. H. Henager, Journal of Nuclear Materials, 258-263, 1998, 1557-1561
[33] C.H. Henager Jr., R.H. Jones, Journal of the American Ceramic Society, 77,1994, 2381
[34] Michio Takeda, Yoshikazu Imai, Yutaka Kagawa, Shu-Qi Guo, Mater. Sci. Eng. A, 286 ,2000, 312-323.
[35] T. Hinoki, L.L. Snead, Y. Katoh, A. Kohyama, R. Shinavski, “The effect of neutron-irradiation on the shear properties of SiC/SiC composites with varied interface” Journal of Nuclear Materials. 283-287,2000, 376-379.
[36] Takashi Nozawa, Kazumi Ozawa, Sosuke Kondo, Tatsuya Hinoki, Yytai Katoh, Lance L. Snead, Akira Kohyama, J. ASTM International, March 2005, Vol.2, No.3
[37] T. Taguchi, T. Nozawa, N. Igawa, Y. Katoh, S. Jitsukawa, A. Kohyama, T. Hinoki, L.L. Snead, “Fabrication of advanced SiC fiber/F-CVI SiC matrix composites with SiC/C multi-layer interphase” Journal of Nuclear Materials.. 329-333, 2004,572-576
[38] H. Kishimoto , Y. Katoh , A. Kohyama “Microstructural stability of SiC and SiC/SiC composites under high temperature irradiation environment” Journal of Nuclear Materials 307–311 ,2002, 1130–1134.
[39] W. Zhang et. al., T. Hiniki, Y. Katoh, A. Kohyama, T. Noda, T. Muroga, J. Yu, Journal of Nuclear Materials. 1577. ,1998, 258-263
[40] T.Ishikawa, "SA-Tyrannohex-based Composite for High Temperature Applications”, Advances in Science and Technology, 71, pp. 118-126, 2010
[41] SA-Tyrannohex report, UBE industry.
[42] T. Ishikawa, S. Kajii, K. Matsunaga, T. Hogami, Y. Kohtoku, T. Nagasawa “A Tough, Thermally Conductive Silicon Carbide Composite with High Strength up to 1600°C in Air ” Science, 282, 1998, 1295-1297.
[43] T.Ishikawa, Y.Kohtoku, K.Kumagawa,T. Yamamura, T.Nagasawa , “High-strength alkali-resistant sintered SiC fibre stable to 2200 ℃”,Nature,391, 1998,773-775.
[44] T.Ishikawa, S.Kajii, K.Matsunaqa, T.Hoqami, Y.Kohtoku, T.Naqasaqa ,“A tough, thermally conductive silicon carbide composite with high strength up to 1600℃ in air”, Science, 282, 1998, 1295-2697
[45] C.Y. Ho, S.C. Tsai, H.T. Lin,F.R. Chen, J.J. Kai, “Microstructural investigation of Si-ion-irradiated Single Crystal 3C-SiC and SA-Tyrannohex SiC Fiber-bonded Composite at High Temperatures”, Journal of Nuclear Materials, vol. 443, 2013,1
[46] Yueh K, Carpenter D, Feinroth H, Clad in Clay. “Nucl Eng Int” , 2010,6-14
[47] George Griffith , U.S. Department of Energy Accident Resistant SiC Clad Nuclear Fuel Development, Oct. 2011
[48] Y. Katoh , Ozawa K, Hinoki T, Choi YB, L. L. Snead, Hasegawa A, “Mechanical properties of advanced SiC fiber composites irradiated at very high temperatures”, Journal of Nuclear Materials, 20, 2011,416-417
[49] L. L. Snead, Nozawa T, Y. Katoh, Byun TS, Kondo S, Petti DA, “Handbook of SiC properties for fuel performance modeling”, Journal of Nuclear Materials , 77, 2007, 329-371
[50] Y.Katoh, Nozawa T, S L. L. Snead, Ozawa K, Tanigawa H. “Stability of SiC and its composites at high neutron fluence”, Journal of Nuclear Materials, 5, 2011, 400-417
[51] Jones RH, Henager CH. “Subcritical crack growth processes in SiC/SiC ceramic matrix composites”, Journal of the European Ceramic Society, 25, 2005,1717-1722
[52] L. L. Snead, Y.Katoh, Connery S. “Swelling of SiC at intermediate and highirradiation temperatures”, Journal of Nuclear Materials, 367, 2007, 677-684
[53] L.H. Rovner and G.R. Hopkins, Nuclear Technology, 29, 274, 1976
[54] Zinkle S. J. “Fusion materials science: overview of challenges and recent progress”, Phys Plasmas, 12, 2005
[55] Jones RH, Giancarli L, Hasegawa A, Katoh Y, Kohyama A, Riccardi B. “Promise and challenges of SiCf/SiC composites for fusion energy applications”. Journal of Nuclear Materials, 307, 2002, 1057–1072
[56] Y. Katoh, L. L. Snead, I. Szlufarska, W. J. Weber, “Radiation effects in SiC for nuclear structural applications”, Current Opinion in Solid State and Materials Science, 16, 2012, 143–152
[57] H.L. Heinisch, L.R. Greenwood, W.J. Weber, R.E. Williford, “Displacement damage in silicon carbide irradiated in fission reactors” Journal of Nuclear Materials 327 ,2004, 175-181.
[58] T. Taguchi, N. Igawa, S. Miwa, E. Wakai, S. Jitsukawa, L.L. Snead, A. Hasegawa,“Synergistic effects of implanted helium and hydrogen and the effect of irradiation temperature on the microstructure of SiC/SiC composites” Journal of Nuclear Materials 335 ,2004, 508–514
[59] A.Hasegawa et. al.," Study of hydrogen effects on microstructural development of SiC base materials under simultaneous irradiation with He- and Si-ion irradiation conditions", Journal of Nuclear Materials 329–333 ,2004, 582–586
[60] T. Taguchi, N. Igawa, S. Miwa, E. Wakai, S. Jitsukawa, L.L. Snead, A. Hasegawa, “Effect of displacement damage up to 50 dpa on microstructural development in SiC/SiC composite”, Journal of Nuclear Materials 367–370 ,2007,698–702
[61] Shuhei Miwa, Akira Hasegawa, Tomitsugu Taguchi, Naoki Igawa, Katsunori Abe “Cavity Formation in a SiC/SiC Composite under Simultaneous Irradiation of Hydrogen, Helium and Silicon Ions”, Materials Transactions, Vol. 46, No. 3 ,2005,536 -542
[62] Hirotatsu Kishimoto, Kazumi Ozawa, Sosuke Kondo, Akira Kohyama" Effects of Dual-Ion Irradiation on the Swelling of SiC/SiC Composites" aterials Transactions, Vol. 46, No. 8 ,2005, 1923-1927
[63] T.S.Duh, K.M. Yin, J.Y. Yan, P.C. Fang, C.W. Chen, J.J. Kai, F.R. Chen, Y. Katoh, A. Kohyama, “Study of helium bubble formation in SiCf/PyC/β-SiC composites by dual-beam irradiation”, Journal of Nuclear Materials 329–333 ,2004,518–523
[64] H.T.Keng , S.W. Li, S.W. Wu, Ji-Jung Kai, Fu-Rong Chen, Y.Katoh, A. Kohyama, “Cavity formation in Tyranno-SA SiCf/SiC composite irradiated with multiple-ion beam at elevated temperatures”, Journal of Nuclear Materials 367–370 ,2007, 753–757
[65] 曾子懷, "Hi-Nicalon type S碳化矽纖維/複合材料應用於核融合Tokamak 結構材料輻射效應之研究",2005
[66] A. Nagasawa, M. Saito, S. Nogami, K. Abe, R.H. Jones, H. Takahashi , “Helium-bubble formation behavior of SiCf/SiC composites after helium implantation”, Journal of Nuclear Materials 264 ,1999, 355–358
[67] L. Vincent, T. Sauvage, G. Carlot, P. Garcia, G. Martin, M.F. Barthe, P. Desgardin, "Thermal behaviour of helium in silicon carbide: Influence of microstructure",Vacuum 83 ,2009,S36–S39
[68] S. Miro , J.M. Costantini , J. Haussy , L. Beck , S. Vaubaillon , S. Pellegrino, C. Meis, J.J. Grob, Y. Zhang, W.J. Weber ," Nuclear reaction analysis of helium migration in silicon carbide" , Journal of Nuclear Materials 415,2011,5-12
[69] T.Sauvae, G. Carlot, G. Martin, L. Vincent, P. Garcia, M.F. Barthe, A. Gentils, P. Desgardin, "Helium behavior in α-SiC ceramics investigated by NRA technique", Nuclear Instruments and Methods in Physics Research B257 ,2007, 231-235
[70] Ruihuan Li, Wenbo Li ,Chong Zhang ,Pengbo Zhang ,Hongyu Fan , Dongping Liu ,Levente Vitos, Jijun Zhao, "He–vacancy interaction and multiple He trapping in small void of silicon carbide", Journal of Nuclear Materials 457 ,2015,36-41
[71] Y. Katoh, N. Hashimoto, S. Kondo, L.L. Snead, A. Kohyama, “Microstructural development in cubic silicon carbide during irradiation at elevated temperatures”, Journal of Nuclear Materials, 351, 2006, 228-240
[72] Akira Kohyama, Kazuya Shimoda, Tatsuya Hinoki, Hirotatsu Kishimoto "Enchanced high-temperature performances of SiC/SiC compositesby high densification and crystalline structure", Journal of Nuclear Materials, 71 ,2011,326-332
[73] H. Kishimoto , K. Ozawa , O. Hashitomi ,Akira Kohyama "Microstructural evolution analysis of NITE SiC/SiC composite using TEM examination and dual-ion irradiation", Journal of Nuclear Materials, 367-370 ,2007, 748-752
[74] Graeme Ackland," Controlling Radiation Damage", MATERIALS SCIENCE ,327, 2010
[75] Weizhong Han and E.G. Fu," Irradiation damage of single crystal, coarse-grained, and nanograined copper under helium bombardment at 450 °C", Journal of Material research, vol.28,No.20, 2013
[76] W. Jiang, H. Wang, I. Kim, I.-T. Bae, G. Li, P. Nachimuthu, Z. Zhu, Y. Zhang, W.J. Weber " Response of nanocrystalline 3C silicon carbide to heavy-ion irradiation" PHYSICAL REVIEW B, 80, 161301,2009
[77] J.F. Ziegler, J.P. Biersack, and U. Littmark, “Stopping and Range of Ions in Solids” , Pergamon Press, New York, 1985, Vol. 1
[78] M.E. Sawan, N.M. Ghoniem, L. Snead, Y. Katoh “Damage production and accumulation in SiC structures in inertial and magnetic fusion systems” Journal of Nuclear Materials 417 ,2011, 445–450
[79] L.L. Snead, R.H. Jones, A. Kohyama, P. Fenici “Status of silicon carbide composites for fusion” Journal of Nuclear Materials. 233-237 ,1996,26-36.
[80] 科儀叢書3, 材料電子顯微鏡學, 國科會精儀中心
[81] 汪建民, 杜正恭, 材料分析 中國材料科學學會 1998.
[82] R. F. Egerton, “Electron-energy loss spectroscopy in the electron microscopy “, Plenum Press, New York, 1996
[83] H. Shuman, C. F. Chang and A. P. Somlyo, Ultramicroscopy, 19, pp. 121, 1986
[84] F. Hofer and P. Warbichler, Ultramicroscopy, 63,1996 ,21

[85] N. Bonnet, C. Coliex, C. Mory and M. Tence, “Scanning Microscopy 2(Suppl.)”, 1988, 351
[86] A. Berger, J. Mayer and H. Kohl, Ultramicroscopy, 55,1994,101
[87] P. A. Crozier and R. F. Egerton, Ultramicroscopy, 27, 1988, 9
[88] D. B. Williams and C. B. Carter, Transmission Electron Microscopy, Plenum Press. New York & London, 1996
[89] T. Malis, S. Cheng and R. F. Egerton, J. Electron. Microsc. Tech., 8, 1988, 8471
[90] T. jacka Bus, "Properties of Silicon Carbide", 2001
[91] P. lung, "Diffusion and retention of helium in graphite and silicon carbide", Journal of Nuclear Materials.191-194 ,1992, 377-381
[92] S. Kondo, Y. Katoh, L.L. Snead, “Microstructural defects in SiC neutron irradiated at very high temperatures”, Journal of Nuclear Materials 382 ,2008, 160–169.
[93] 何雋禹, "利用超高解析電鏡分析單晶3C-碳化矽與SA-Tyrannohex全纖維碳化矽複合材料在高溫矽離子輻照下之缺陷", 2013
[94] 林協弘,"單晶3C碳化矽於離子輻照下之微結構變化與膨脹效應",(2015)
[95] Zinkle,"Effect of H and He irradiation on cavity formation and blistering in ceramics", Nuclear Instruments and Methods in Physics Research B 286,2012, 4-19.
[96] T. Ohshima , A. Uedono , K. Abe , H. Itoh , Y. Aoki , M. Yoshikawa , S. Tanigawa ,I. Nashiyama "Characterization of vacancy-type defects and phosphorus donors introduced in 6H-SiC by ion implantation", Applied Physics A,67,1998, 407-412,
[97] C.H.Chen ,Y. Zhang ,E. Fu ,Y. Wang ,M.L. Crespillo ,C. Liu ,S. Shannon ,W.J.Weber "Irradiation-induced microstructural change in helium-implanted single crystal and nano-engineered SiC", Journal of Nuclear Materials, 453, 2014 ,280-28
[98] Yudi PRAMONO , Kazunari SASAKI , Toyohiko Yano "Release and Diffusion Rate of Helium in Neutron-Irradiated SiC",Journal of Nuclear Science and Technology ,2012,751-755
[99] Fei Gao ,William J. Weber, M. Posselt, V. Belko "Atomistic study of intrinsic defect migration in 3C-SiC" , PHYSICAL REVIEW B 69, 245205 ,2004