Dynamics of ion irradiation defects

离子辐照缺陷动力学

• 批准号: 09680492
• 负责人: UEDA Yoshio
• 金额: $ 1.6万
• 依托单位: Osaka University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09680492/
• 关键词: ion irradiation defects; radiation enhanced sublimation; chemical sputtering; high flux; graphite; boron-doped graphite; silicon-doped graphite; flux dependence; 高粒子束ビーム

We have investigated radiation enhanced sublimation of graphite and chemical sputtering of graphite under high flux beam irradiation (up to 10ィイD122ィエD1 mィイD1-2ィエD1sィイD1-1ィエD1) to study the dynamics of ion irradiation defects and its effects on the above-mentioned erosion processes of graphite. The obtained results are as follows :1. Radiation enhanced sublimation of isotropic graphite was investgated with 5keV Ar beam with the flux up to 10ィイD121ィエD1mィイD1-2ィエD1sィイD1-1ィエD1). It is found that as irradiation flux exceeds 10ィイD120ィエD1mィイD1-2ィエD1sィイD1-1ィエD1 erosion yield decreases rapidly with flux as ΦィイD1-0.26ィエD1 (Φ : flux). This flux dependence is much stronger than the previous low flux results (< 10ィイD120ィエD1mィイD1-2ィエD1sィイD1-1ィエD1, ΦィイD1-0.1ィエD1). According to self-interstitial diffusion theory, flux dependence of erosion yield of radiation enhanced sublimation might be elucidated provided that sinks for interstitials are stable defects for low irradiation flux (< 10ィイD120ィエD1mィイD1-2 … More ィエD1sィイD1-1ィエD1) and vacancies for high irradiation flux (>10ィイD120ィエD1mィイD1-2ィエD1sィイD1-1ィエD1).2. Measurements of chemically sputtered methane (CDィイD24ィエD2) were made with 5 keV DィイD3+(/)3ィエD3 beam irradiation by a quadrupole mass analyser installed in a differential pumping chamber. Samples were isotropic graphite (JG-430), CFC graphite (CX2002), boron-doped graphite (GB series, boron content 0% to 20%), and silicon-doped graphite (TS processed graphite). It is found that peak temperature at which methane signals took maximum increased with flux up to about 1000 K. This temperature was not observed previously (less than 850 K) and could be considered as a high flux effect. In addition, methane yield (methane signal divided by flux) did not show flux dependence. These results are not consistent with a typical chemical sputtering model made by Roth et al. under the assumption that the annealing effects of graphite prevents methyl group formation above the temperature of 800 K. Chemical sputtering yield of boron-doped graphite is reduced by about a factor of 3 compared with pure graphite samples. For silicon-doped graphite with the atomic ration of about 1/1. Chemical sputtering was almost suppressed. Less

我们研究了高通量辐照(高达10ィイD122ィエd1 mィイd1-2ィエd1sィイd1-1ィエd1)下石墨的辐照升华和石墨的化学溅射，以研究离子辐照缺陷的动力学及其对上述石墨腐蚀过程的影响。1.用5keV的Ar束对各向同性石墨的辐照升华进行了研究，注量高达10ィイD121ィエD1MィイD_1-2ィエD_1SィイD_1-1ィエD_1)。结果表明，当辐照剂量超过10ィイD120ィエD1MィイD_1-2ィエD_1sィイD_1-1ィエD_1时，ΦィイD_1-0.26ィエD_1(Φ：焊剂)的腐蚀产额随辐照剂量的增加而迅速下降。这种磁通依赖性比以前的低磁通结果(&lt；10ィイD120ィエD1MィイD1-2ィエD1sィイD1-1ィエD1，ΦィイD1-0.1ィエD1)强得多。根据自间隙扩散理论，只要在低辐照通量(&lt；10ィイD120ィエD1MィイD_1-2…)下，间隙的吸收是稳定的缺陷，则辐射增强升华侵蚀产额的通量依赖性可能被阐明。更多ィエD1sィイd1-1ィエd1)和高辐照通量的空缺(&gt；10ィイd120ィエd1mィイd1-2ィエd1sィイd1-1ィエd1)2.化学溅射甲烷(CdィイD24ィエD2)用5 keV DィイD3+(/)3ィエD3束流照射，在差动泵浦室内安装四极质谱仪进行测量。样品包括各向同性石墨(JG-430)、氯氟化碳(CX2002)、掺硼石墨(GB系列，含硼0%~20%)和掺硅石墨(TS处理石墨)。结果表明，甲烷信号的峰值温度随着流量的增加而增加，当流量达到1000K时，甲烷信号的峰值温度增加，这是以前没有观测到的温度(小于850K)，可以认为是一种高通量效应。此外，甲烷产率(甲烷信号除以通量)不表现出通量依赖性。这些结果与Roth等人提出的典型化学溅射模型不一致。在假定石墨的退火效应防止了800K以上的甲基团形成的情况下，掺硼石墨的化学溅射产额比纯石墨样品降低了约3倍。对于原子比约为1/1的掺硅石墨，化学溅射几乎被抑制。较少

项目成果

Y. Ueda et al.: "Erosion and Surface Morphology of Graphtie Materials under High Flux Beam Irradiation"J. Nucl. Mater.. 258-263. 628-633 (1998)

Y. Ueda 等：“高通量束辐照下石墨材料的侵蚀和表面形态”J。

Y.Ohtsuka et al.: "Erosion of Pyrolytic Graphite and Ti-doped Graphite due to High Flux Irradiation"Journal of Nuclear Science and Technology. 34. 792-798 (1997)

Y.Ohtsuka 等人：“高通量辐照引起的热解石墨和掺钛石墨的侵蚀”核科学与技术杂志。

Y. Ohtsuka et al.: "Erosion of Pyrolytic Graphite and Ti-doped Graphite due to High Flux Irradiation"J. Nucl. Mater.. 34. 792-798 (1997)

Y. Ohtsuka 等人：“高通量辐照引起的热解石墨和掺钛石墨的侵蚀”J。

M.Nishikawa: "High Flux Dependence of Erosion and Retention in Beam Experiments and its significance to Fusion Systems" Fusion Engineering and Design. 41. 47-53 (1998)

M.Nishikawa：“梁实验中侵蚀和保留的高通量依赖性及其对聚变系统的意义”聚变工程与设计。

M.Nishikawa: "High Flux Dependence of Erosion and Retention in Beam Experiments and its Significance to Fusion Systems"Fusion Engineering and Design. 41. 47-53 (1998)

M.Nishikawa：“光束实验中侵蚀和保留的高通量依赖性及其对聚变系统的意义”聚变工程和设计。