Combined application of laser-induced breakdown spectroscopy original position statistic distribution analyzer and electron microprobe in element segregation analysis of CrMo wear resistant steel
1. Center for Advanced Solidification Technology (CAST), School of Materials Science and Engineering, Shanghai University,Shanghai 200444, China; 2. Baoshan Iron and Steel Co., Ltd., Shanghai 201900, China; 3. Stainless Steel R&D Center, China Baowu Central Research Institute,Shanghai 200126, China
Abstract：CrMo wear-resistant cast steel is an important wear-resistant steel material. The solute element segregation in the solidification process is an important factor affecting the microstructure and properties of CrMo wear-resistant cast steel. The understanding of solute element segregation in the solidification process is of great significance to the industrial production of CrMo wear-resistant cast steel. Macrosegregation and microsegregation are two indicators to measure the degree of segregation of materials. The accurate measurement of segregation status is the basis for studying solute element segregation. The CrMo wear-resistant cast steel was selected as the research object. The macrosegregation in different parts of the steel ingot and the microsegregation in the solidification structure were measured by laser-induced breakdown spectroscopy original position analyzer (LIBSOPA) and electron probe microanalyzer (EPMA). The results showed that the macrosegregation degree of Cr, V and Mn in the CrMo wear-resistant cast steel ingot was small, and the segregation ratio was close to 1. But the macrosegregation degree of Mo was large, and the maximum macrosegregation ratio was more than 1.20. The microsegregation of Cr, Mo, V and Mn existed in the solidification structure of CrMo steel. Moreover, the microsegregation degree of Cr, Mo, V and Mn increased with the increase of cooling rate, and the maximum microsegregation ratio was 1.39, 2.63, 3.47 and 1.83, respectively. The combined application of LIBSOPA and EPMA in the analysis of element segregation in CrMo wear-resistant cast steel had important reference significance for the comprehensive understanding of element segregation in CrMo steel ingots as well as the optimization of casting and subsequent hot processing technology.
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