Method for quantitatively characterizing dendrite segregation and dendrite spacing of high-temperature alloy ingot

A method for quantitatively characterizing a dendrite segregation and dendrite spacing of a high-temperature alloy ingot, comprising:

• step 1:
• preparation and surface treatment of the high-temperature alloy ingot,
• cutting off a certain size block high-temperature alloy ingot sample, and grinding or polishing a characteristic section;
• step 2:
• selection of a calibration sample and determination of an element content,
• selecting a series of block spectrum standard samples or uniform block alloys with a element composition and structure close to those of the high-temperature alloy sample,
• measuring a content of each element in the calibration sample by using a national standard method to obtain a chemical composition analysis result of the calibration sample, and
• grinding or polishing a surface of the calibration sample;
• step 3:
• establishment of a quantitative method for elements in a micro-beam X-ray fluorescence spectrometer,
• measuring a calibration sample by using the micro-beam X-ray fluorescence spectrometry, obtaining an instrument initial element quantitative analysis result, and
• performing a linear regression fitting on a chemical component analysis result of step 2 and a fluorescence spectrum initial measurement result to obtain a high-temperature alloy element content calibration equation;
• step 4:
• quantitative distribution analysis of element components of the high-temperature alloy,
• performing an analysis and test on the high-temperature alloy bulk sample by using the micro-beam X-ray fluorescence spectrometry under the same conditions in step 3,
• calibrating an element content of the obtained data matrix by using the quantitative calibration equation in step 3 to obtain a two-dimensional distribution map of the content of each element, the distribution orientation of the primary dendritic structure and the space between adjacent primary dendrites;
• step 5:
• quantitative characterization of characteristic element line distribution of high-temperature alloy,
• according to the two-dimensional element content distribution map obtained in step 4, selecting elements with obvious dendrite distribution characteristics for line distribution quantitative characterization to obtain a characteristic element content line distribution map;
• step 6:
• analysis of a characteristic element line distribution map and statistics of a secondary dendrite spacing,
• calculating an average spacing of the secondary dendrite and a segregation ratio of the element within the range according to the line distribution map of the characteristic element.