Original Position Statistic Distribution Analysis of Trace Element Segregation in Nickel-base Super Alloy by LA-ICP-MS

摘要

A new original position statistic distribution analysis method to reflect the different composition distribution and segregation in nickel-base super alloy was developed by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). This distribution of more than 20 trace elements at intragranular solid solution phase and crystal boundary in wrought super alloy GH698 was investigated using the micro-area analysis of LA-ICP-MS technique. For most of the trace elements, no significant difference was found between the content in the crystalline grain and that at the crystal boundary. Only a few elements such as Mg, Zr, B and P showed slight segregation at crystal boundary. However, according to the compositional two-dimensional isohypsic chart and statistic degree of segregation, which was obtained by original position statistic distribution method combined with LA-ICP-MS, the segregation of As, Mg and Te was more serious in the cross section scope (10 mm × 10 mm) of the wrought super alloy sample. The results showed that the original position statistic distribution analysis results were in good agreement with the crystal boundary segregation and eutectic structure enrichment obtained by metallographic analysis.