共查询到19条相似文献,搜索用时 62 毫秒
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采用气相渗透方法,开展了国产低活化铁素体/马氏体钢(RAFM钢?)之一的CLAM钢的氚渗透实验,研究了影响渗透的关键因素,建立了可靠的实验方法。在573~823?K温度范围内,得出氚的渗透率FT为2.57×10-8exp(-38639/RT),氚溶解度ST为2.2×10-1exp(-38639/RT),扩散系数DT?为1.17×10-7exp(-22011/RT)。另外,氘氚混合渗透时存在明显的正同位素效应,在实验温度范围内,推导得出的氘氚渗透分离系数αDT为1.42,氕氚渗透分离系数αHT为3.76。 相似文献
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一、引言铀与氚有较强的化学反应,这种反应随氚的压力和温度的增加而加剧。当氚在金属(?)中的浓度低于铀对氚的固溶极限时,氚与铀发生非常缓慢的氚化反应,这时,氚从高浓度端 相似文献
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用热解吸和静态贮存方法对贮氚非晶态ZrV2合金膜中3He的释放行为进行了系统分析。结果显示:3He原子存在597.3、725.8和1 146.6 K等3个解吸峰,其中第3解吸峰的解吸量最大,是由非晶态基体中的3He释放形成;在长达2 423 d的静态贮存期间,非晶膜中3He原子的释放系数始终在10-5量级范围内波动并呈线性上升趋势,但仍未加速释放;贮存温度变化会引起释放系数剧烈波动;与贮氚晶态ZrV2合金膜相比,非晶膜的固氦能力显著增强。上述结果初步证实了非晶合金具有良好的固氦性能,这有助于人们从全新视角认识材料中的氦行为。 相似文献
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采用气相吸附法研究了室温下RAFM钢表面对氚的吸附与释放行为,并使用316L钢、1Cr18Ni9Ti钢进行了对照实验。结果表明,RAFM钢表面的氚吸附与释放性质与316L钢、1Cr18Ni9Ti钢的非常相似,相同表面状态的样品,在相同实验条件下的吸附氚量相差不超过50%。可推测,未经深度除水处理的RAFM钢暴露于氚后,表面会形成富氚层,浓度远高于基体溶解氚,厚度不大于10 μm。表面氚的形态以化学吸附和物理吸附的氚化水为主,约占90%以上。室温下RAFM钢表面吸附的氚在干燥气氛中的释放非常缓慢,但遇水会因氚-水间的同位素交换而加速释放。 相似文献
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为研究氚在高温气冷堆核级石墨上的吸附和解吸附行为,本文利用密度泛函理论,采用氢原子代替氚原子的办法,通过理论计算得到了氚在高温气冷堆核级石墨上的结合能,通过模型分析得到了氚在高温气冷堆核级石墨上的吸附、解吸附机理与相应的份额,并得到HTR-10在20年寿期末各部分氚的累积量及事故工况下氚释放量的估计值。本文结果为研究估算高温气冷堆氚释放的机理提供了一条新思路。 相似文献
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【日本《原子能视野》2002年4月刊报道】 日本原子能研究所在TOKARO公司的协助下,成功开发出了在高温条件下能够将氚的渗透量降低到1/1000的陶瓷保护膜。 1. 开发背景 未来的核聚变反应堆要求在再生区实施减少渗氚措施,与未实施减少渗氚措施的情况相比,400℃下渗氚量之比(渗透减少率)小于1/100。为了降低再生区容器构造材料(假定为铁素体钢)的渗氚量,采用了在再生区容器内壁及用于发电的排热冷却管外壁设置密实并耐高温的陶瓷保护膜的方法,但容器内壁施工未获成功,而且也没有找到满足条件的材料。 原研得到拥有各种陶瓷保护膜施工技术的T… 相似文献
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阻氚涂层是聚变堆实现氚自持及氚安全的关键科学与技术问题之一。我国通过国家磁约束聚变能发展研究专项依托国内优势单位部署了阻氚涂层基础问题及工程化技术研发工作。本文介绍了国内外聚变堆结构材料表面阻氚涂层研究进展,重点评述了近几年我国在阻氚涂层的材料选择、制备技术及阻滞氢渗透机制三个科学技术问题的研究进展,提出今后的研究方向。目前我国阻氚涂层材料类型以氧化物涂层为主,涂层制备工艺技术在不断优化和更新。Al2O3/FeAl阻氚涂层的电化学沉积铝(ECA)、粉末包埋渗铝(PC)及热浸铝(HDA)等方法的工艺处理规模及涂层阻氚性能在国际上均相对领先。发展了研究阻氚涂层阻滞氢渗透作用机理的方法,将通常基于Fick定律的表象研究方法向原子级方法前推了一步。未来需在考虑涂层制备工艺与基体材料成分、性能的关系及其在复杂形状结构件的适用性基础上,开发长寿命、高阻氚性能的阻氚涂层材料及制备工艺。 相似文献
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Exposures of concrete and selected coating materials to tritiated atmospheres have shown that tritium sorption on these materials and subsequent desorption are important parameters in defining tritium sources within a tritium-handling facility. Exposure time, tritium concentration and humidity of the air atmosphere affected the amount of tritiated water vapor sorbed. Some of the selected coatings reduced the tritium sorbed to less than 1% of unprotected concrete samples.Work funded by AECL Research and the Canadian Fusion Fuels Technology Project (CFFTP). 相似文献
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《Journal of Nuclear Science and Technology》2013,50(11):1007-1013
In a fusion blanket design, ceramic coating on structural materials has been considered to be used as a tritium permeation barrier. The Chemical Densified Coating (CDC) method has some advantage compared with another coating method. This method is capable to form densified coating on either the outer or the inner surface of a tube or a container. This process temperature is low (450°C). The fabrication technique of Cr2O3-SiO2 coating had been developed using CDC method. However, Cr2O3-SiO2 coating had open pores in the coating. For filling open pores, the densification treatment by CrPO4 was examined. In this study, the verification of open pores, the thermal shock resistivity, the adhesion strength and the deuterium permeability were evaluated and compared with Cr2O3-SiO2 (Type 1) coating and Cr2O3-SiO2 including CrPO4 (Type 2) coating. From these results, it was confirmed that Type 2 coating had a good adhesion property, and permeation reduction factor of SS316 with Cr2O3-SiO2 including CrPO4 coating reached about 1,000 at 600°C. 相似文献
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《Journal of Nuclear Science and Technology》2013,50(12):1522-1529
In Korea, a nuclear hydrogen program has been established to develop and demonstrate mass production system for hydrogen generation. The objective of this study is to establish the evaluation procedure for predicting the tritium behavior in the 300 MWth Pebble type gas cooled reactor which is the one of the candidate reactors for nuclear hydrogen development and demonstration plant. The tritium generated by the fission reaction can be leaked to the helium coolant from the coated ceramic particles and fuel elements. The annual total release rate of the tritium is estimated as 0.47% from the fuel kernel to the helium coolant by the numerical method. Tritium attributed by 6Li existing as impurities in the reflector can be released to the helium coolant by the diffusion process and the total annual release rate of the tritium is estimated as 5.3% through the reflector to the helium coolant. Based on the Siverts' law, tritium permeation from the primary coolant to the hydrogen production system is also evaluated and the result is calculated as 76?0.23 Bq/g-H2 with respect to the PRF (Permeation Reduction Factor= 10?1000) in case of the normal operation of the 300 MWth Pebble type reactor. 相似文献
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在分别采用光学显微镜和辉光放电光谱仪获得S22合金钢的金相显微组织和元素成分的基础上,利用已经过氘渗透速率定量标定的渗透实验装置,研究了S22合金钢在400~600℃下的氘扩散渗透行为,得到了氘在S22合金钢中的渗透率和扩散系数。对比分析了500℃时纯D2和He+1%D2下S22合金钢的氘渗透数据,结果表明,随氘分压的降低,氘在S22合金钢中的扩散渗透孕育期增加,氘渗透速率降低,但即使在较低氘分压下依然有氘渗透现象。该结果可为高温气冷堆、快堆等先进反应堆在使用S22合金钢时进行必要的氚渗透防护及其安全分析提供理论与数据支持。 相似文献