第三代SiC纤维及其在核能领域的应用现状
国防科技大学 新型陶瓷纤维及其复合材料重点实验室, 长沙 410073
Third Generation SiC Fibers for Nuclear Applications
Science and Technology on Advanced Ceramic Fibers and Composites Laboratory, National University of Defense Technology, Changsha 410073, China
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收稿日期: 2019-06-20 修回日期: 2019-07-29 网络出版日期: 2020-05-20
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Received: 2019-06-20 Revised: 2019-07-29 Online: 2020-05-20
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作者简介 About authors
王堋人(1990-),男,博士研究生.E-mail:nudtwpr@163.com
WANGPengren(1990-),male,PhDcandidate.E-mail:nudtwpr@163.com
第三代SiC纤维具有近化学计量比的元素组成和高结晶致密的特性, 与第一、第二代SiC纤维相比, 在耐高温、抗氧化、抗蠕变及抗辐射等性能上均有明显的提升, 因此在工程应用上尤其在核能领域拥有更明显的优势和更广阔的前景。本文对第三代SiC纤维的制备工艺、性能特点进行了介绍和比较, 综述了第三代SiC纤维在核能领域的应用, 并对其发展前景进行了展望。
关键词:
The third generation SiC fibers have near-stoichiometric composition and polycrystallinity with high density. Compared with the first and second generations, they have obvious improvements in heat-resistance, creep-resistance and radiation-resistance. Accordingly, they have more advantages and broader prospects in engineering applications, especially in the nuclear field. In this paper, the fabrication and performance characteristics of the third generation SiC fibers are introduced and compared. The applications of the third generation SiC fibers in the field of nuclear energy are reviewed, and the development prospects are prospected.
Keywords:
本文引用格式
王堋人, 苟燕子, 王浩.
WANG Pengren, GOU Yanzi, WANG Hao.
连续SiC纤维具有高强度、高模量、耐高温抗氧化、辐照条件下的活性低等优异性能[1,2,3], 自从1975年Yajima等[4]以聚碳硅烷(Polycarbosilane, PCS)为先驱体制备细直径连续SiC纤维以来, SiC纤维得到了迅猛发展, 到目前为止已经从富碳富氧且处于无定形态的第一代SiC纤维发展到具有近化学计量比和高结晶特性的第三代SiC纤维[5]。目前市售第一代SiC纤维以日本碳公司(Nippon Carbon Co. Ltd.)生产的Nicalon 200、日本宇部兴产公司(Ube Industries)生产的Tyranno Lox-M和国防科技大学生产的KD-I为代表, 由于氧含量偏高(~12wt%), SiC纤维在1200 ℃以上强度迅速下降[6,7,8,9]。通过改进纤维交联工艺, 第二代SiC纤维实现了无氧不熔化, 显著降低了氧含量(可达1wt%以下), 在惰性气氛下可以在1500 ℃以下保持较高的拉伸强度和模量, 典型代表有Hi-Nicalon、Tyranno ZE、KD-II等, 但由于碳含量偏高(C/Si≈1.4), 其抗氧化性能仍然不够理想[5,10-12]。因此, 日本碳公司、宇部兴产公司和美国Dow Corning公司分别采用不同的技术路线研制出了近化学计量比的第三代SiC纤维, 商品号分别为Hi-Nicalon S、Tyranno SA和Sylramic(以及Sylramic-iBN), 中国国防科技大学则研制出了KD-S(与Hi-Nicalon S类似)和KD-SA(与Tyranno SA类似)两种第三代SiC纤维。
图1
表1列出了所有三代SiC纤维的组成和力学特性, 总体来看, 三代SiC纤维在拉伸强度上并没有明显区别, 均在3.0 GPa左右, 而在杨氏模量上则是依次升高。第一代SiC纤维中包含大量富余碳和氧, 其结构由β-SiC微晶(<5 nm)、自由碳和无定型相SiCxOy组成[19,20]; 第二代SiC纤维富碳, 主要由β-SiC微晶(5~10 nm)和自由碳组成[5]; 第三代SiC纤维在组成上是近化学计量比, 由大尺寸的β-SiC晶粒(达到100 nm以上)形成致密结构[1]。研究表明, 由于存在SiCxOy晶间相和自由碳限制了SiC结晶, 高温下SiCxOy晶间相容易分解、滑移, 自由碳易氧化, 因此第三代SiC纤维与前两代相比, 耐温性、抗氧化性和抗蠕变性能都显著升高[21,22,23,24,25]。
Trade mark | Tensile strength/GPa | Young’s modulus/GPa | Diameter/μm | C/Si | |
---|---|---|---|---|---|
First generation | Nicalon 200 | 3.0 | 200 | 14 | 1.33 |
Tyranno Lox-M | 3.3 | 185 | 11 | 1.38 | |
KD-I | >2.5 | >170 | 11.5 | 1.29 | |
Second generation | Hi-Nicalon | 2.8 | 270 | 12 | 1.39 |
Tyranno ZE | 3.5 | 233 | 11 | 1.34 | |
KD-II | >2.7 | >250 | 11.5 | 1.35-1.40 | |
Third generation | Hi-Nicalon S | 2.6 | 340 | 12.0 | 1.05 |
KD-S | 2.7 | 310 | 11.0 | 1.08 | |
Tyranno SA | 2.8 | 375 | 8.0&10.0 | 1.08 | |
KD-SA | 2.5 | 350 | 10.5 | 1.05 | |
Sylramic | 3.2 | 400 | 10.0 | 1.01 |
图2
图3
1 第三代SiC纤维的组成和性能特点
图4
Hi-Nicalon S纤维是采用电子束辐照实现无氧交联, 其氧含量可以降低到1wt%以下。值得注意的是, 电子束交联是在惰性气氛中进行的, 一方面可以防止纤维在活性状态下被氧化, 另一方面利用气氛带走辐照产生的热量, 避免纤维在高温下熔并。交联后的纤维在1500 ℃左右H2气氛中烧成, 去除富余碳。由于制备温度较低, Hi-Nicalon S纤维的晶粒尺寸(~100 nm)小于其他第三代SiC纤维(~200 nm)的晶粒尺寸, 当温度高于1500 ℃时, 晶粒会快速长大, 导致纤维结构从致密变疏松, 强度下降, 这限制了Hi-Nicalon S纤维在高温部件中的应用。但Hi-Nicalon S纤维抗氧化性能较好, 在干燥空气中1400 ℃处理10 h, 拉伸强度仍有1.8 GPa[29], 而且它在辐照条件下结构和性能稳定, 可用于先进核能领域。KD-S纤维的制备工艺与Hi-Nicalon S类似, 其拉伸强度高达2.7 GPa, 在惰性气氛中1600 ℃处理后强度没有降低, 1800 ℃处理1 h后强度仍有1.63 GPa[13]。
Tyranno SA纤维是通过聚碳硅烷(PCS)和乙酰丙酮铝(Al(AcAc)3)反应合成聚铝碳硅烷(PACS), 经纺丝、空气不熔化和高温处理得到的。在不熔化过程中引入氧, 可以在后续高温处理过程中利用SiCxOy的分解(见反应(2)和(3))同时去除多余的氧和碳, 该过程生成气态产物, 因此纤维内部不可避免地会留下孔洞, 通过引入烧结助剂Al可以使纤维在1800 ℃以上实现烧结致密化, 消除孔洞缺陷, 得到的纤维晶粒尺寸较大, 可达200 nm。与Hi-Nicalon S纤维的电子束辐照相比, SA型纤维的生产设备廉价、条件易控, 因此可以大幅度降低生产成本。
Tyranno SA纤维在Ar气氛中2000 ℃处理1 h, 拉伸强度仍保留80%, 空气中1000和1300 ℃处理100 h, 拉伸强度分别保留100%和55%。同时, 由于Tyranno SA还拥有其它纤维不具备的抗碱腐蚀性[21], 因此用其增强的SiC基复合材料部件可以应用在靠近海洋或者处于含有碱性元素的燃烧气氛中。KD-SA与Tyranno SA的制备工艺类似, 性能接近, 晶粒尺寸200 nm左右, 在拉应力作用下, 该纤维展现出穿晶断裂, 在惰性气氛中1800 ℃处理5 h和1900 ℃处理1 h(高温处理后的纤维形貌见图5)强度基本不变, 在空气中1300 ℃处理1 h的强度保留率可达97%[14,30-32]。
图5
Sylramic纤维是以聚钛碳硅烷(PTC)为先驱体, 经熔融纺丝、空气不熔化处理后, 在纤维烧成过程中通过含硼化合物(如BCl3, BF3、BBr3和硼烷等)的反应及扩散, 将烧结助剂B元素引入纤维中, 将Sylramic纤维在含N气氛中进一步加热, 将富余的B从晶界中去除, 并在纤维表面生成BN膜, 即得到Sylramic-iBN纤维。与Sylramic纤维相比, Sylramic-iBN纤维晶粒更大, 晶界更干净, 抗蠕变性能和电导率进一步提高, 抗氧化性也得到增强[33]。
总之, 第三代SiC纤维不仅C/Si比接近化学计量比、氧含量更低, 而且Tyranno SA、KD-SA和Sylramic纤维等具有高结晶致密的特性, 使其具有更好的耐高温和高温抗蠕变性能。
2 第三代SiC纤维在复合材料制备工艺上的优势
连续SiC纤维增强SiC复合材料(SiCf/SiC)主要应用于高温、强氧化、强腐蚀及辐照条件下的结构部件, 如航空涡轮发动机叶片、喷气式发动机燃烧机的内衬、核聚变反应堆包层结构、包层流道内衬和转化器等[34,35,36,37]。随着应用领域技术的发展, 对SiCf/SiC复合材料的耐温性、抗氧化性、热导率和气密性等性能的要求越来越高。陶瓷基复合材料的制备工艺经过几十年的发展已经趋于成熟, 目前制备SiCf/SiC复合材料的主要工艺有化学气相渗透(Chemical Vapor Infiltration, CVI)、先驱体浸渍裂解(Polymer Infiltration and Pyrolysis, PIP)、熔渗(Melt Infiltration, MI)和纳米浸渍瞬时共晶相(Nano-powder Infiltration and Transient Eutectoid, NITE)等。
从制备工艺的角度来看, 第三代SiC纤维同样具有更大的优势。以第一、二代SiC纤维为增强体时, 一般采用制备温度较低(900~1200 ℃)的CVI和PIP工艺, 这两种工艺在制备过程中, 纤维不需要经历1400 ℃以上高温, 所得SiCf/SiC也就不具备高结晶、高致密化的特征, 因此无法满足高温应用领域的要求。Riccardi等[38]采用CVI工艺制备了2D和3D Tyranno SA/SiC复合材料, 其杨氏模量分别为293和198 GPa, 剪切强度分别为54和45 MPa。MI工艺制备温度高于Si的熔点(1410 ℃), 一般在1400~1600 ℃范围内[39,40], 对纤维损伤较大, 目前只有Tyranno SA、KD-SA和Sylramic-iBN第三代纤维的制备温度高于MI工艺温度, 因此纤维在制备复合材料的过程中损伤较小。Morscher等[41]对MI工艺制备的Sylramic/SiC复合材料进行了抗蠕变和疲劳测试, 结果表明, 该材料在220 MPa的应力水平下可以保持500 h不失效。类似MI的方法也被用于SiCf/SiC部件的反应连接(Reaction bonding), 要求所连接的部件中SiC纤维能够承受1500 ℃高温[42]。同样地, NITE工艺要在1700~1800 ℃的高温和15~20 MPa的高压条件下进行, 现有连续SiC纤维中只有TyrannoSA、KD-SA和Sylramic满足NITE工艺过程中的高温高压条件。在用NITE方法制备复合材料的研究方面, 已有采用TyrannoSA 纤维作为增强体的研究报道[43,44]。Kishimoto等[45]研究了NITE-Tyranno SA/SiC复合材料的辐照性能(辐照粒子为Si离子和He离子, 温度为1200 ℃, 剂量为60 dpa), 除了产生少量的微腔外, 其他无明显变化, 表现出良好的稳定性。
表2统计了不同型号SiC/SiC复合材料在室温和高温的性能, 可以看出第三代Sylramic、Sylramic- iBN和Hi-Nicalon S纤维制备的复合材料可以在更高的温度下保持稳定性。
Brand name | Fiber type | Preparation technology | Tensile strength at room temperature / MPa | Failure duration |
---|---|---|---|---|
Hypercomp PP-HN | Hi-Nicalon | MI | 321 | >1000 h/1200 ℃ |
Hypercomp SC-HN | Hi-Nicalon | MI | 358 | >1000 h/1200 ℃ |
N22 | Sylramic | CVI+MI | 400 | ~500 h/1204 ℃ |
N24-A | Sylramic-iBN | CVI+MI | 450 | ~500 h/1315 ℃ |
N24-B | Sylramic-iBN | CVI+MI | 450 | ~500 h/1315 ℃ |
N24-C | Sylramic-iBN | CVI+MI | 310 | >1000 h/1315 ℃ |
N26 | Sylramic-iBN | CVI+PIP | 330 | ~300 h/1450 ℃ |
A410 | Hi-Nicalon | CVI | 200-315 | 600 h/1200 ℃ |
A416 | Hi-Nicalon S | CVI | 200-315 | 200 h/1400 ℃ |
3 第三代SiC纤维在核能领域的应用
核聚变反应堆的结构材料长期处于高温、高辐照和高应力的苛刻条件下, 以含有大量SiCxOy无定型相或β-SiC微晶(<10 nm)为特点的第一和第二代SiC纤维制备的SiCf/SiC复合材料, 经辐照后会引发SiCxOy相的分解、无定型态的结晶和β-SiC晶粒的长大(图6), Nicalon纤维和Hi-Nicalon纤维经辐照后, 纤维的密度均出现了增大, 意味着纤维体积收缩严重, 易导致纤维和基体剥离, 最终使SiCf/SiC失效[47,48]。第三代SiC纤维具有近化学计量比的组成, 几乎不含SiCxOy相, 并且结晶度高(图6), Tyranno SA纤维与CVD法制备的SiC经辐照后密度基本不变, 说明由二者制备SiCf/SiC复合材料在辐照条件下结构稳定, 更有利于在核能领域的应用。但是Sylramic-iBN纤维中含的B、N元素在辐射环境中会发生嬗变并产生长寿命的同位素, 不适宜用于聚变反应堆结构材料[49]。以Tyranno SA和 Hi-Nicalon S纤维作为增强体, 在辐照条件下制备SiCf/SiC复合材料的研究报道[50], 主要是应用在包层的第一壁、流道插件、控制棒及偏滤器等部件[35,51-53]。
图6
图7
反应堆中的结构材料承受高的热载荷, 具有高的热导率(λ)有利于减少热应力, 所以希望获得具有较高热导率的SiCf/SiC复合材料[56]。而使用CVI工艺制备的Nicalon纤维增强SiC基复合材料在室温下的热导率仅为10 W/(m·K), PIP工艺制备的SiCf/SiC复合材料的热导率更低, 不能很好地满足核反应堆对结构材料的要求[57,58,59,60]。第三代SiC纤维热导率则较高, Hi-Nicalon S为18 W/(m·K), Tyranno SA更是高达65 W/(m·K)。Yamada等[61]分别以Tyranno SA和Hi-Nicalon S为增强体, 通过CVI方法制备了3D SiCf/SiC复合材料, 并研究了热导率。前者在室温和1000 ℃下的热导率分别为40~50和24 W/(m·K), 后者则分别为36和20 W/(m·K)。
图8
图9
5 结束语
第三代SiC纤维拥有比前两代更优异的耐温性能, 使其在制备SiCf/SiC复合材料时可以经受更高的制备温度, 提高了复合材料的性能; 同时近化学计量比、高结晶的特性也使其在辐照条件下能够保持自身结构稳定, 在核能领域的应用具有明显优势。
目前第三代SiCf/SiC复合材料在核能领域的应用方面需要关注以下几点:
1) 虽然第三代SiC纤维和SiC基体在辐照条件下比较稳定, 但其界面相(常见有PyC界面相、BN界面相和复合界面相)却不稳定, 改进界面相的耐辐照性能十分关键;
2) 气密性是SiCf/SiC复合材料在核能领域应用中需要考察的重要性能, 随着核技术的发展, 应用环境条件更加苛刻, 对气密性的要求也会越来越高;
3) SiCf/SiC复合材料与冷却剂和增殖剂的化学相容性对其服役寿命以及核反应堆的能量转换效率有重要影响, 需要进一步研究;
4) 在工业化生产中需进一步降低成本。
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Fabrication, microstructure, properties and applications of continuous ceramic fibers: a review of present status and further directions
Fabrication of nearly stoichiometric polycrystalline SiC fibers with excellent high-temperature stability up to 1900 ℃
DOI:10.1111/jace.2018.101.issue-1 URL [本文引用: 3]
KD系列连续碳化硅纤维组成、结构与性能关系研究
Effects of heat treatment on the microstructures and properties of KD-I SiC fibres
The microstructure and elctrical resistivity of near-stoichiometric SiC fiber
Understanding Nicalon Fibre
DOI:10.1016/0955-2219(93)90040-X URL [本文引用: 1]
Evidence for a silicon oxycarbide phase in the Nicalon silicon carbide fibre
DOI:10.1007/BF00660966 URL [本文引用: 1]
High-strength alkali-resistant sintered SiC fibre stable to 2,200 ℃
Properties of Stoichiometric Silicon Carbide Fiber Derived from Polycarbosilane
Processing and Structural Advantages of the Sylramic-iBN SiC Fiber for SiC/SiC Components
New type of SiC- sintered fiber and its composite material
Advances in inorganic fibers
Creep limitations of current polycrystalline ceramic fibers
Tokyo Metropolitan government has decided to make the maximum possible use of the existing facilities while ensuring safety against inundation and to promote measures also from a software approach by introducing a system capable of minimizing combined sewer overflow, the real-time control system (RTC). A pilot RTC system was installed in August 2002 for the Shinozaki Pumping Station. The RTC system monitors the precipitation volume and the water level in the pipe. Simulations were carried out on the basis of these data. From the results, it was found that with the use of the RTC it is possible to reduce CSO by roughly 50% for small rainfalls with a total precipitation level of 20 mm or less by strong rainwater in the pipe routes at the beginning of the rain. It has also been shown that CSO can be reduced by about 80% through the use of rainfall forecasting.
Reaction mechanisms of silicon carbide fiber synthesis by heat treatment of polycarbosilane fibers cured by radiation, part 1evolved gas analysis
DOI:10.1111/jace.1995.78.issue-4 URL [本文引用: 3]
Recent advances in Nicalon ceramic fibres including Hi-Nicalon type S
A detailed study of the microstructure and thermal stability of typical SiC fibers
DOI:10.1016/j.matchar.2018.09.041 URL [本文引用: 1]
Polyaluminocarbosilane as precursor for aluminium- containing SiC fiber from oxygen-free sources
DOI:10.1016/j.ceramint.2016.03.191 URL
Facile synthesis of melt- spinnablepolyaluminocarbosilane using low-softening-point polycarbosilane for Si-C-Al-O fibers
DOI:10.1007/s10853-016-0101-7 URL [本文引用: 1]
Comparison of the Tensile, Creep, and Rupture Strength Properties of Stoichiometric SiC Fibers
Intermediate-temperature stress rupture of a woven Hi-Nicalon, BN-interphase, SiC- matrix composite in air
DOI:10.1111/jace.2000.83.issue-6 URL [本文引用: 1]
Current status and critical issues for development of SiC composites for fusion applications
DOI:10.1016/j.jnucmat.2007.03.032 URL [本文引用: 2]
Formation of carbon-rich layer on the surface of SiC fiber by sintering under vacuum for superior mechanical and thermal properties
DOI:10.1016/j.jeurceramsoc.2016.10.013 URL [本文引用: 1]
The high-temperature corrosion behavior of SiBCN fibers for aerospace applications
DOI:10.1021/acsami.8b04497
URL
PMID:29767945
[本文引用: 1]
Amorphous SiBCN fibers possessing superior stability against oxidation have become a desirable candidate for high-temperature aerospace applications. Currently, investigations on the high-temperature corrosion behavior of these fibers for the application in high-heat engines are insufficient. Here, our polymer-derived SiBCN fibers were corroded at 1400 °C in air and simulated combustion environments. The fibers' structural evolution after corrosion in two different conditions and the potential mechanisms are investigated. It shows that the as-prepared SiBCN fibers mainly consist of amorphous networks of SiN3C, SiN4, B-N hexatomic rings, free carbon clusters, and BN2C units. High-resolution transmission electron microscopy cross-section observations combined with energy-dispersive spectrometry/electron energy-loss spectroscopy analysis exhibit a trilayer structure with no detectable cracks for fibers after corrosion, including the outermost SiO2 layer, the h-BN grain-contained interlayer, and the uncorroded fiber core. A high percentage of water vapor contained in the simulated combustion environment triggers the formation of abundant α-cristobalite nanoparticles dispersing in the amorphous SiO2 phase, which are absent in fibers corroded in air. The formation of h-BN grains in the interlayer could be ascribed to the sacrificial effects of free carbon clusters, Si-C, and Si-N units reacting with oxygen diffusing inward, which protects h-BN grains formed by networks of B-N hexatomic rings in original SiBCN fibers. These results improve our understanding of the corrosion process of SiBCN fibers in a high-temperature oxygen- and water-rich atmosphere.
Characterization of commercial grade Tyranno SA/CVI-SiC composites
DOI:10.1016/j.jnucmat.2007.03.098 URL [本文引用: 1]
Making ceramic composites by melt infiltration
Stress-dependent matrix cracking in 2D woven SiC-fiber reinforced melt-infiltrated SiC matrix composites
Creep in vacuum of woven Sylramic-iBN melt-infiltrated composites
Microstructure and mechanical properties of reaction- formed joints in reaction-bonded silicon carbide ceramics
DOI:10.1023/A:1004489712447 URL [本文引用: 1]
Advanced SiC fibers and SiC/SiC composites toward industrialization
DOI:10.1016/j.jnucmat.2010.12.086 URL [本文引用: 1]
Processing optimization and mechanical evaluation of hot pressed 2D Tyranno-SA/SiC composites
DOI:10.1016/S0955-2219(02)00298-4 URL [本文引用: 1]
Microstructural evolution analysis of NITE SiC/SiC composite using TEM examination and dual-ion irradiation
DOI:10.1016/j.jnucmat.2007.03.043 URL [本文引用: 1]
Research and application of polyimide composites for aeroengine
The effect of high dose/high temperature irradiation on high purity fibers and their silicon carbide composites
The effect of irradiation on the stability and properties of monolithic silicon carbide and SiCf/SiC composites up to 25 dpa
DOI:10.1016/0022-3115(94)00391-2 URL [本文引用: 1]
The effect of neutron irradiation on silicon carbide fibers
Continuous SiC fiber, CVI SiC matrix composites for nuclear applications: properties and irradiation effects
DOI:10.1016/j.jnucmat.2013.06.040 URL [本文引用: 1]
Materials research towards a fusion reactor
Recent advances and issues in development of silicon carbide composites for fusion applications
Compatibility of PIP SiCf/SiC with LiPb at 700 ℃
DOI:10.1016/j.fusengdes.2010.04.060 URL [本文引用: 1]
High-dose neutron irradiation of Hi-Nicalon type S silicon carbide composites. Part 2: Mechanical and physical properties
DOI:10.1016/j.jnucmat.2014.12.121 URL [本文引用: 3]
Promise and challenges of SiCf/SiC composites for fusion energy applications
A fusion power reactor concept using SiC/SiC composites
Status of silicon carbide composites for fusion
Critical issues and current status of SiCf/SiC composites for fusion
Effects of neutron irradiation on thermal conductivity of SiC-based composites and monolithic ceramics
DOI:10.13182/FST96-A11963060 URL [本文引用: 1]
Radiation resistant ceramic matrix composites
DOI:10.1016/j.dental.2010.10.002
URL
PMID:21093035
[本文引用: 1]
To investigate the surface integrity of solvent-challenged ormocer-matrix composites, photoactivated by different light exposure modes, through surface-hardness measurements at different periods of time; and to compare such behavior with dimethacrylate-based materials.
Thermal diffusivity/conductivity of Tyranno SA fiber- and Hi-Nicalon type S fiber-reinforced 3-D SiC/SiC composites
Prototype tokamak fusion reactor based on SiC/SiC composite material focusing on easy maintenance
Review of blanket designs for advanced fusion reactors
DOI:10.1016/j.fusengdes.2008.07.039 URL [本文引用: 1]
The EU advanced lead lithium blanket concept using SiCf/SiC flow channel inserts as electrical and thermal insulators
Divertor conceptual designs for a fusion power plant
DOI:10.1016/j.fusengdes.2008.05.022 URL [本文引用: 1]
Potential performances of a divertor concept based on liquid metal cooled SiCf/SiC structures
Thermal insulator of porous SiC/SiC composites for fusion blanket system
SiC/SiC and W/SiC/SiC composite heater by NITE-method for IFMIF and fission reactor irradiation rigs
DOI:10.1088/1757-899X/18/16/162018 URL [本文引用: 3]
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