GCr15轴承钢精炼渣冷却过程矿相析出热力学分析和应用

采用FactSage热力学计算及实验室研究相结合的方法,研究了碱度（R）2.5~5.4、Al₂O₃（14%~30%）和MgO（3%~15%）对GCr15轴承钢CaO-Al₂O₃-SiO₂-MgO四元精炼渣矿相析出的影响,结果表明,1 600℃时,随着碱度由2.4增加至5.4,硅酸盐类矿物的析出量由56%降低至30%,Ca₃Al₂O₆、Ca₃MgAl₄O₁₀和CaAl₂O₃三种矿物的总析出量从28.0%增加至58.2%;当渣中Al₂O₃含量由14%增加至30%时（R4.4,7%MgO）,析出的金属氧化物固溶体由26%降低到3.5%,硅酸盐类矿物析出量由42%降低到33%,Ca₃Al₂O₆、Ca₃MgAl₄O₁₀和CaAl₂O₃三种矿物的析出量则由32.2%增大到63.2%;当渣中MgO含量由5%增加至15%时（R4.4,26%Al2O3）,硅酸盐类矿物,Ca₃Al₂O₆、Ca₃MgAl₄O₁₀和CaAl₂O₄析出量变化并不显著。当碱度4~5,4.5%~5.5%MgO,24%~27%Al₂O₃时,四元渣具有适宜的黏度和熔化温度,有较好的流动性和吸附夹杂物能力。热态重熔实验确定的渣系矿相组成与热力学模拟结果一致。

Analysis on Thermodynamic of Mineralogical Phases Precipitation in Refining Slag for Bearing Steel GCr15 during Cooling Process and Application

With using Factsage thermodynamic calculation and test in laboratory, the effect of basicity (R)2.5 -5.4, Al₂O₃ (14%-30% ) and MgO (3%-15% ) content on mineralogical phases precipitation in CaO-Al₂O₃-SiO₂-MgO quaternary refining slag for bearing steel GCr15 has been studied. Results show that at 1 600 °C , with basicity of slag increasing from 2.4 to 5.4, the amount of precipitation of silicate mineral in slag decreases from 56% to 30% , the total precipitation amount of three kinds of minerals of Ca₃Al₂O₆、Ca₃MgAl₄O₁₀ and CaAl₂O₃ increases from 28. 0% to 58. 2% ； with increasing Al₂O₃ content in slag from 14% to 30% (R4. 4, 7% MgO),, the precipitated metal oxide solid solution amount decreases from 26% to 3. 5% , silicate minerals decrease form 42% to 33% , while the precipitated amount of three kinds of minerals of Ca₃Al₂O₆、Ca₃MgAl₄O₁₀ and CaAl₂O₃ increases from 32. 2% to 63.2% ； and with increasing MgO content in slag from 5% to 15% (R4.4, 26% Al₂O₃) , the change of precipitated amount of silicate minerals, Ca₃Al₂O₆、Ca₃MgAl₄O₁₀ and CaAl₂O₄ is not obvious. With basicity of slag 4-5, 4. 5%-5. 5% MgO and 24%-27% Al₂O₃, the quaternary slag has suitable viscosity and melting temperature , and has better fluidity and ability to absorb inclusions in liquid. The thermodynamic simulation results are consistent with the results of mineralogical phases ingredient defined by hot status remelting experiment.