High Resolution Secondary Ion Mass Spectrometry Studies of Lithium in Aluminum

本研究的两个相关目标是：继续改进高分辨率扫描离子微探针分析系统，并将其应用于提高对铝锂合金的认识。该计划旨在定量测定铝锂合金中锂的分布。这需要对二次离子质谱法的空间分辨率进行初步研究，建立锂离子和铝离子信号比作为锂浓度函数的标准，并确定铝锂合金中锂的可检测性。铝锂合金将被检查以测量锂在第二相、晶界和断口表面的分布，以获得锂在这些合金中的偏析的理解。结果将与利哈伊大学的透射电子显微镜研究相关联。系统中的相稳定性将通过离子注入和老化处理的样品来确定。结果将与国家标准局使用中子深度剖面的研究相关联。

This research has two related goals, as follows: continued improvement of the high resolution scanning ion microprobe analysis system and its application to improved understanding of aluminum-lithium alloys. The program is directed towards quantitative determination of the distribution of lithium in aluminum-lithium alloys. It requires initial studies on the spatial resolution of secondary ion mass spectrometry, creation of standards for the lithium and aluminum ion signal ratios as a function of lithium concentration, and determination of detectability of lithium in aluminum-lithium alloys. Aluminum- lithium alloys will be examined to measure the distribution of lithium in second phases, at grain boundaries, and at fracture surfaces to gain understanding of the segregation of lithium in these alloys. Results will be correlated with transmission electron microscopy studies at Lehigh University. Phase stability in the system will be determined using samples undergoing ion implantation and ageing treatments. Results will be correlated with studies using neutron depth profiling at the National Bureau of Standards.