提高转炉出钢碳含量的生产实践研究

转炉采用终点低拉碳法生产中高碳钢,钢水氧含量高,后续脱氧难度大、钢中夹杂物多。基于降低生产成本和提高钢水洁净度的双重目的,进行了提高中高碳钢出钢碳含量的可行性分析及生产实践。通过优化供氧枪位和改进加料方案,实现了吹炼前期高效脱磷、中后期强化脱磷并抑制脱碳,将转炉单渣操作的出钢碳含量由原来的平均0.06%提高到0.10%~0.20%范围内,钢水磷含量控制在0.016%以下。     

掺杂sc的CaZrO3的制备及电学性能

采用掺杂Sc₂O₃,通过固相反应法制备了CaZr_1-xSc_xO_3-α（x=0,0.1,0.15）材料.在610-850℃采用交流阻抗谱法测定了CaZr_1-xSc_xO_3-α的电导率及电导激活能,并对CaZrO₃掺Sc及掺In样品的电学性能进行了比较.结果表明:在610-850℃,CaZrO₃的电导率为4.3×10^-19-1.4×10^-6S/cm,CaZr_1-xSc_xO_3-α（x=0.1,0.15）的电导率为1.16×10^-4-1.4×10^-3S/cm,CaZr_1-xIn_xO_3-α（x=0.1,0.15）的电导率为0.34×10^-4-4.33×10^-4S/cm,且随着温度的升高而提高;掺杂能极大提高CaZrO₃的电导率,并随着掺杂量的增加,电导激活能降低,电导率增加;温度及掺杂量相同时,掺Sc材料电导率明显高于掺In材料,说明掺Sc对提高材料的电导率更有效.     

Preparation and sintering properties of zirconia-mullite-corundum composites using fly ash and zircon

Zirconia-mullite-corundum composites were successfully prepared from fly ash,zircon and alumina powder by a reaction sintering process.The phase and microstructure evolutions of the composite synthesized at desired temperatures of 1 400,1 500 and 1 600°C for 4 h were characterized by X-ray diffractometry and scanning electronic microscopy,respectively.The influences of sintering temperature on shrinkage ratio,apparent porosity and bulk density of the synthesized composite were investigated.The formation process of the composites was discussed in detail.The results show that the zirconia-mullite-corundum composites with good sintering properties can be prepared at 1 600°C for 4 h.Zirconia particles can be homogeneously distributed in mullite matrix,and the zirconia particles are around 5μm.The formation process of zirconia-mullite-corundum composites consists of decomposition of zircon and mullitization process.