二次离子质谱（SIMS）分析混合堆材料表面涂层成份深度分布的方法研究

【作者】 武昌平；

【导师】 李金英； 李安利；

【作者基本信息】 中国原子能科学研究院 ， 分析化学， 2004， 硕士

【摘要】 聚变-裂变混合堆设计方案中，可采用Li₁₇Pb₈₃作为冷却剂和产氚剂。含氚液态金属有很强的腐蚀性和渗透性，因而钢冷却管道内壁应有防渗屏障层。用表面渗铝氧化方法形成微米厚度的Al₂O₃／FeAl涂层，是广泛研究的防渗屏障层生成工艺。实验测量其微观结构、表面成份及深度分布，对于改进工艺，探索最佳工艺条件具有重要意义。 二次离子质谱（SIMS）的重要功能之一是分析固体样品表面成份的深度分布。本工作在CAMECA IMS 6F上进行马氏体钢表面Al₂O₃／FeAl涂层分析方法的研究。样品的基材包括两种马氏体钢：EUROFER-97和CLAM。用表面渗铝氧化方法形成的涂层结构复杂，包含多种元素。分析成份主要是铝、铁、氧，重点是它们的深度分布和铝的氧化程度随深度的变化。由于待测元素既包含金属元素又包含非金属元素，故本工作的实验中，使用了两种入射离子束：O₂⁺和Cs⁺。用O₂⁺一次束入射测量正二次离子，用Cs⁺一次束入射主要测量负二次离子。 在SIMS完成涂层成份深度分析过程中，对一次束流强、轰击时间、二次离子收集面积、二次离子种类、二次离子能量范围和质量分辨率等实验参数进行研究，建立了实验分析方法。应用于实际样品的测量，对实验数据进行分析比较、取舍验证，表明方法可靠。 实验中发现，这种复杂样品的基体效应很强，尤其铯源测定金属负离子时基体效应严重。依据前人的研究成果，本工作试图采用MCs⁺-SIMS技术进行测量，以便减弱基体效应，实验中发现MCs⁺的基体效应确实比M^-低，但在相同分辨率时，MCs⁺二次离子的强度远低于M^-二次离子的强度，可达3至4个数量级。 为了检验SIMS深度分析实验方法的可靠性，本工作使用电子探针微区分析方法（EPMA）对同一样品进行横截面深度分析，对分析结果进行了比较。 研究结果表明，精心选择实验条件，使用SIMS对渗铝氧化涂层进行深度分析是可行的，获得的成份深度分布和氧化程度随深度变化的相对曲线，与电子探针微区分析结果一致。更多还原

【Abstract】 Li17Pb83 will be a coolant in designing Fusion-Fission Hybrid Reactor, as well as a tritium producer. The liquid metal with tritium has high permeability and corrosiveness, so the inner surface of the steel coolant piping should be coated with a tritium permeation barrier. An Al2O3/FeAl coating with thickness of micrometers is formed by packed-bed aluminizing and oxidizing technology. Experimental measurements of microstructure, components and depth profile of the coating are important for improvements of coating technology.One of the basic functions of Secondary Ion Mass Spectrometry (SIMS) is the depth profile analyses in solid samples. This work has been performed by CAMECA IMS 6F, and has developed an analytical method for depth profile of aluminized coatings in two types of Martensitic steel: EUROFER-97 and CLAM. Characterized components are Al, Fe and O. The depth profile is not only showed, but also the oxidation grade has been gained. Two primary beams of O2+ and Cs+ are used in this work. The positive secondary ions are measured with O2+ beam .The negative secondary ions are mainly measured with Cs+ beam.During the depth profile analyses with SIMS, beam intensity, bombardment time, secondary ion species, collected area, energy range of the secondary ions and mass resolution are studied in the experiments. After measurements of the samples, the experimental data are analyzed and examined. These samples with many elements and complex structure show strong matrix effects, especially for negative metallic ions. According to other scientists’ results, MCs+ are measured in our experiments for decreasing the matrix effects, but the intensity of MCs+ are less than that of M" by 3 to 4 magnitude order.The experimental results indicate that the depth profiling technology with SIMS is available for analyses of the packed-bed aluminizing coating. But the experimental conditions should be selected carefully. Relative density curves of the components are obtained and in agreement with the result by electron probe microanalyses.更多还原