Abstract:In order to study elemental segregation and precipitation characteristics during solidification process of continuous casting for Fe-Mn-Al-C system medium manganese steel, the microstructure of Fe-5Mn-2Al-0.15C medium manganese steel was observed by optical microscope. Solidification mode, solute elemental segregation and precipitation behavior were investigated by Thermo-Calc thermodynamics software. The results show that the microstructure of medium manganese steel ingot is mainly lamellar martensite and contains a small amount of ferrite. Its solidification mode is liquid→liquid+δ-ferrite→liquid+δ-ferrite+γ-austenite→δ-ferrite+γ-austenite→γ-austenite. The equilibrium partition coefficient of element Al is greater than 1 and undergoes negative segregation by segregating into the dendrite interior of δ-ferrite. Mn, Nb, V, S and other solute elements undergo positive segregation and all of them are converged to interdendrite. AlN is mainly precipitated in dendrites and the precipitation temperature is 1 448 ℃, while MnS, enrichments of Nb and V are mainly precipitated in interdendrites. MnS and Nb-rich precipitates begin to precipitate above 1 400 ℃, while the precipitation temperature of enrichment of V is 760 ℃.
金立斌, 郑淑国, 朱苗勇. Fe-5Mn-2Al-0.15C中锰钢连铸凝固偏析及粒子析出行为[J]. 中国冶金, 2021, 31(12): 27-31.
JIN Li-bin, ZHENG Shu-guo, ZHU Miao-yong. Elemental segregation and precipitation behavior during solidification process of continuous casting for Fe-5Mn-2Al-0.15C medium manganese steel[J]. China Metallurgy, 2021, 31(12): 27-31.
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