Characterization Of The Element Distribution And Quantitative Segregation Degree Of Nickel-Based Superalloy Ingot

: Segregation defects cannot be eliminated from nickel-based superalloy prepared by smelting. Thus, studying the element-content distribution and segregation degree is helpful to guide process improvement and quality control. In this study, the cross section of a cylindrical electro-slag remelting ingot of a wrought superalloy with a diameter of 485 mm was analyzed by micro-beam X-ray fluorescence spectrometry, and continuous point-by-point mode was used to obtain high stability and accuracy. The element-content distribution and quantitative degree of segregation from the edge to the center of the ingot were characterized. The maximum positive segregation, maximum negative segregation, statistic segregation degree, and statistic conformity degree were calculated for each element to quantitatively characterize the degree of segregation from different points of view, and they showed the same trend as the element-content distribution. The results of metallography and scanning electron microscopy with energy-dispersive spectroscopy (SEM-EDS) showed that there were differences in the dendritic microstructures and precipitated phases in the interdendrites and dendritic arms from the edge to the center of the ingot, which explain the element-content distribution largely.